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HP TV Converter Box e User's Manual

1. F CLEANING PRECISION 7mm CONNECTORS Puta drop or two of cleaning solvent in the center of a lint free cleaning cloth Retract the connector sleeve threads Press the contact end of the connector into the cloth and turn it Removing the collet is not necessary Blow the connector dry with a gentle stream of compressed air Keep the cloth clean in a plastic bag or box when it is not in use Figure 5 Cleaning Interior Surfaces and Precision 7mm Connectors Cleaning 13 14 MECHANICAL INSPECTION CONNECTOR GAGES Inspect connectors mechanically using a connector gage before they are used for the first time and periodically after that Use the correct gage type and gage calibration block for the connector being gaged inspect clean and zero the gage before using it Check the zero setting again before each measurement e Connector specifications depend on the device Consult the mechanical specifications provided with the connector or the device itself to determine whether it is within specification Even a perfectly clean unused connector can cause trouble if it is mechanically out of specification Since the critical tolerances in microwave connectors are on the order of a few ten thousandths of an inch using a connector gage is essential Before using any connector for the first time inspect it mec
2. Decimal Value STATUS BYTE 1 A Request SRQ on SRQ on SRQ on SRQ on SRQ on Any Service HP IB Operation Softkey Change in Numeric Front Panel banco SRQ Syntax Error Complete Only Extended Entry Key Pressed Sweep Plot Pressed Status Byte Completed or Print 1 or Front Panel EXTENDED STATUS BYTE 2 ee Fe ok EN on SRQ on SRQ on SRQ on SRQon N A eee Detector Front Panel Limit Test Action Knob Self Test Uncal Preset or Failed Requested Activity Failure Power on not possible immediately A third approach is to use the sweep hold mode SW2 instead of the non swept mode SW0 In this mode the analyzer will prevent any HP IB operations until the completion of the TAKE SWEEP command Program 7 listing 10 DIM Ascii_dat 0 400 20 ASSIGN Sna TO 716 30 ASSIGN Passthru TO 717 40 ABORT 7 50 CLEAR Sna 60 OUTPUT Sna IP 70 OUTPUT GSna PT19 80 OUTPUT Passthru ST250MS 90 OUTPUT gGSna C2C0 IB 100 OUTPUT Sna SW0 CS RM16 110 OUTPUT Sna TS10 120 Stat SPOLL 5na 130 IF BIT Stat 4 0 THEN 120 140 OUTPUT GSna C1OD 150 ENTER Sna Ascii_dat 160 OUTPUT Sna SW1 170 PAUSE 180 OUTPUT Sna SW0 CS RM16 190 ON INTR 7 GOTO Srq recv 200 ENABLE INTR 7 2 210 OUTPUT GSna TS10 220 GOTO 220 230 Srq recv 240 Stat SPOLL Sna 250 OUTPUT Sna 260 OUTPUT S
3. 23 secant cvswst mme 13 measure power voltage commands QRG8 ratio commands QRG 8 measurements bandwidth 20 UG 12 gain compression UG 15 insertionloss UG 12 out of band rejection UG 13 peak to peak ripple UG 13 return loss UG 18 simultaneous UG 18 T ornetur oA UP UG 18 transmission UG 18 measurement memoty 13 measurement minus memory 13 MEM softkey display nA PEE da Ene 12 recall 3 35 eaae rere 48 SAVE 44 Q44 menu structure maps 54 60 message line eee 6 MHz softkey 28 MIN softkey 20 mnemonics HP IB QRG 1 MOD ON OFF softkey 40 MODE AC DC softkey 39 MODE LABELS softkey 35 mode labels 5 MODIFY COLOR softkey 16 modified ASCH character set QRG 20 modulation UG 15 command QRG 11 eds Maite dae 1 8 external 2 11 requirements of source 1 9 MODULATOR DRIVE connector 62 monitor external 2 12 monochrome 16 MONOCHROME softkey 16 N NEXT PAGE softkey recall i2 es 48 uui quc er au Se nee bs 45 INONSTD ON OFF softkey 42
4. 2 13 ot Se yey Naren Ta i Operating Environment 2 13 Measuremen BOER ai PN ao EATE E T Storage and Shipment Environment 2 14 NIS dang ANASWA PO DACKEGING 2 14 Simultaneous Transmission and Reflection Measurements 18 SECTION 3 OPERATION Limit Lines DES 19 Accessing the Limit Menu 19 Meets AIVE 3 1 Creating Flat Limit Lines 19 HP 8757C Firmware Revision History 3 2 Creating Sloped Limit LINS 19 HP 8757E Firmware Revision History 3 3 Creating Point LENS 20 Editing Limit Segments 20 SOCAL OPERATION Creating Limit Lines for a Bandpass Filter 20 Operating Reference Alternate Sweep 21 What Is in this Reference 1 External DISK Drive 22 How to Use this Reference 2 Special Functions yas ERO Ue PEIUS au Pes 24 To Find a Front Panel Key Description 2 Color Selection 24 To Find a Softkey Description 2 Frequency Blanking 24 if You Can t Find a Softkey 3 AC Versus DC Detection 25 HP 8757C E Table of Contents
5. 36 OVINE rei eo AD as 36 UG 10 aboft iL esol kat le ees 38 black and white 36 Rats 37 commands QRG 10 graphicS isse eee 37 tabular iuc sext n eS ances 37 PRINT DATA softkey 37 PRINT ENTRIES softkey 29 PRINT MKRS softkey 37 PRINTER softkey 42 printers compatible 36 problems calibration 2 0 0 2 eee DIF 4 general DIF 3 cis bia eae eae erue DIF line power DIF 2 programming DIF 4 programming differences between analyzers RO1 examples IPG IPV 3 HP 8757C E commands QRG 22 23 IPG 22 IPV 24 softkeys IPG 13 IPV 15 valid characters QRG 3 R PRY 850ftkey oc cs ERE Eis 11 RJA softkey 11 RIB softkey 11 R C softkey 1i rack mount with handles 2 5 2 7 without handles 2 5 2 6 rear panel connectors 61 RECALL key 47 RECALL REGISTR softkey 47 RED softkey 45 REF KOY 1 25 Goes ee we ctu 18 reference level desc Sah eee de Mae bate ade ns 18 level commands QRG 8 POSITION 18 position command QRG 9 step SIZE 18 reflection measurements see measurement
6. 8757C E In Case of Difficulty 1 2 MANUAL OPERATION Line Power Problems if the power switch is turned on but all front panel LEDs remain off and the fan is not operating suspect a power problem Make sure the power line cable is properly connected e Check that the correct line voltage is selected at the rear panel power line module The voltage selector PC board must be correctly installed Refer to section 2 for installation instructions Make sure the correct fuse is installed in the fuse holder of the power line module The required fuse rating for each line voltage is listed in table 2 1 and also below the power line module on the rear panel of the analyzer Error Codes When the front panel PRESET key is pressed the analyzer performs a series of self tests before establishing the preset conditions H any of these tests fail an error code from 1 through 15 is displayed in binary form with lighted LEDs This error code appears in two places on the front panel in the INSTRUMENT STATE HP IB STATUS area using the LEDs labeled R L T and S and on the A3 CPU assembly using four of the eight LEDs near the top left corner of the board These are arranged in an 8 4 2 1 sequence with the most significant bit 8 being on the left In many cases an error message is aiso shown on the CRT The best failure indicators are the LEDs on the CPU assembly since the front panei LEDs will not light in the event of a front
7. Figure 5 CHANNEL Keys The CHANNEL keys are shown in figure 5 The channel is used to take the data received from the detector inputs and show it on the CRT in a format designated by preset conditions or front panel key entry CHANNEL key operation is described in the following text Operating Reference HP 8757C E sees CHANNEL 1 CHANNEL 2 CHANNEL MENU HP 8757C CHANNEL Figure 6 CHANNEL Keys and Channel Menu Pressing either CHANNEL 1 or CHANNEL 2 turns on and activates that channel Only one channel is active at a time although all channels can be turned on for simultaneous viewing The active channel mode labels are enclosed in a highlighted box Any functions entered apply only to the active channel Measurement data however is updated to all channels simultaneously Channel 1 and 2 are turned on at preset and channel 1 is the active channel otherwise the channel number pressed is active HP 8757E users can turn off a channel by pressing that CHANNEL key twice The first press activates the channel the second press turns it off Press the CHANNEL key again to turn the channel back on m ae er oO Either CHANNEL key also presents the channel menu of softkeys shown in figure 6 CHAN 37 and CHAN 4 allow you to turn on and activate those channels Any channel can be turned off when the channel menu is accessed For example when CHAN 1 OFF is pressed the channel 1 trace is removed from th
8. 3 Program 2 Controlling the Front Panel 5 Program 3 Passthru Mode 6 Program 4 Cursor Operations 8 Program 5 Read a Single Value 10 Program 6 Trace Transfer 11 Program 7 Using the TAKE SWEEP Command 14 Program 8 Programming the Softkeys 15 Program 9 CRT Graphics 17 Program 10 Learning the Instrument State 19 Program 11 Guided Instrument Setup with CRT Graphics 21 IN CASE OF DIFFICULTY Introduction MER te eaten edes 1 Manual Operation 2 Line Power Problems 2 Erro Codes uoce xem OE aoc nb OD SOR Ve s 2 System Operation 3 seo d x or d we b e RC eds 3 Genaral Sa OR UR T 3 HP IB Connections and Addresses 3 Other Cable Connections 4 Remote Operation asd inaccurate Operation ed Galibrati i os edece ta cora nTa noa we hele Pa 4 Modulation Characteristics 5 Sweep Speed Sah d AES 5 Miscellaneous Problems Jaded katie a ata Bhd Gog 5 Alternate Sweep 9 Number of Trace Points and Trace Memory 5 Autozero of DC Detectors 6 Save Recall Registers 6 System Interface On Off COPIER 7 Measur
9. dais Ql p VIN e VC ul gt NS ea YY e 75 tO zo Oz or ul lt x x uj TQ xo 23 p 3 P x Co CO LL Ws Or ze v D a C cc wwe CF LLE Aor o Om Ox eu 3 ZO zum oat O uw oe OF S e om Or lt QT z Om ea gt Ze 5 ot se lt Z o a gt _ 29 E e s T lt Oz x 1 1 iL ea N tot 0 a 0 C E ERI Ox NASA KS oO MAN NAXAX XOU e oil ol RANA 55 20000006606 x GAGE CALIBRATION BLOCK 21 Mechanical Inspection 22 Gage Accuracy An important general point about measuring connectors is that setback dimensions are difficult to measure owing to measurement uncertainties of the connector gages typically one small division on the dial and to variations in technique from user to user For example using a gage with 0 0001 inch small divisions on the dial to measure a connector that has an actual setback of 0 0005 inches may result in gage readings from 0 0004 to 0 0006 inches depending on the gage Note that this range of readings is possible due strictly to the measurement uncertainty of the gage Other variables such as cleaning and gage technique can cause still further variations to appear between measurements of exactly the same connector For these
10. male precision 3 5mm female precision 3 5mm precision 7mm precision 7mm HP Part Number 1250 1746 HP Part Number 1250 1747 4 slot center conductor collets HP Part Number 85052 60004 HP Part Number 85052 60003 6 slot precision center conductor collets Itt nee Figure 25 3 5mm Adapters 2 of 2 SMA and Precision 3 5mm Connectors 63 64 HP 85021 27 series Directional Bridges Reducing wear due to SMA connectors may also influence the choice of equipment For example when devices with SMA connectors are to be mea sured at frequencies from 10 MHz to 18 GHz using an HP 85027 series directional bridge Hewlett Packard recommends using the HP 85027A 7mm directional bridge and 7mm to 3 5mm adapters If a slight loss in directivity can be tolerated this arrangement is much better than using the HP 85027B 3 5mm directional bridge and connecting the SMA devices directly to it in part because the 7mm interface because it is larger is more rigid and durable The 7mm to 3 5mm adapter serves as a connector saver in this application it is much easier and much cheaper to replace an adapter than it is to repair the bridge Some idea of the effects on electrical performance when connector saver adapters are used may be seen in Figure 26 Typical directivity of the HP 85021 27 directional bridges with connector saver adapters in place is compared to the 40 dB directivity up to 18GHz specification of the bridges alone A
11. 0208 5 0012 D FUNCTION OF DIELECTRIC P FA CONSTANT WITH A BORE 002 9 4 OF 161 162 THE WALL 00 e f 15 0 009 0015 Ly 000 004 APC 3 5 SMA y bs S Cui x 5 MAMA MAM rr LLL VI La Figure 23 Precision 3 5mm Connector and Precision 3 5mm SMA Connector Interfaces SMA and Precision 3 5mm Connectors PRECISION 3 5mm INTERFACE 59 60 Electrical Performance Electrically junctions coupled with precision 3 5mm connectors only exhibit greatly superior trical performance compared to junctions coupled with SMA connectors or with an SMA connector connected to a precision 3 5mm connector Typical values are shown in Figure 24 As will be seen when an SMA connector is mated with a precision 3 5mm connector the connection itself exhibits a mismatch SWR typically about 1 10 at 20 GHz This mismatch is less than is obtained when two SMA connectors are mated But it is still much higher than occurs when precision 3 5mm connectors alone are used Keep this fact in mind when making measurements on SMA and precision 3 5mm coupled junctions SWR 115 1 10 SMA SMA INTERFACES SMA PRECISION 3 5mm INTERFACES 1 05 PRECISION 3 5mmy i PRECISION 3 5mm INTERFACES 1 00 0 01 FREQUENCY IN GHz 26 5 Figure 24 Typical SWR of Precision 3 5mm and SMA Coupled Junctions SMA and Precision 3 5mm Connectors Adapters Adapters are used for two m
12. 10 Cleaning Interior Surfaces 12 Precision 7mm Connectors 12 Drying Connectors 12 MECHANICAL INSPECTION CONNECTOR GAGES 14 Mechanical Specifications 14 Precision 7mm Connectors 15 Type N Connectors 16 75Q Type N Connectors 16 SMA and Precision 3 5mm Connectors 17 Types of Gages 19 Using Connector Gages 20 Inspecting and Cleaning the Gage 20 Zeroing the Gage 20 Measuring Connectors 20 22 MAKING CONNECTIONS 23 General Connection Technique 24 Align Connectors Carefully 24 Make a Preliminary Connection Lightly 24 Use a Torque Wrench to Make the Final COMECON voe rea Ges eke du e vs ides 26 Type N and NMD 3 5 Connectors 29 Excessive Connector Nut Tightness Precision 7mm Connectors 29 Disconnection 30 PART TWO CONNECTOR TYPES Precision 7mm Connectors 31 MECHANICAL SPECIFICATIONS OF PRECISION 7mm CONNECTORS 32 Cleaning Precision 7mm Connectors 32 Removing Center Conductor Collets 34 Selecting a Connector Gage 36 Gaging Precision 7mm Connectors 37 Making Connections 40 Seating Precision 7mm Connectors 40 ADAPTERS FOR PRECISION
13. Adaptive normalization off Temperature compensation on m Repeat autozero off SOURCE connected to the 8757 SYSTEM INTERFACE Instrument preset Sweep time set to 200 ms m HP 8350B square wave modulation on m HP 8340 41 SHIFT PULSE on RF Output on m HP 8360 scalar modulation on RF Output on analyzer mode PLOTTER connected to the 8757 SYSTEM INTERFACE m Abort plotifin progress m Pland P2 scaling points unchanged Selection of plotter pens unchanged PRINTER connected to the 8757 SYSTEM INTERFACE m Abortplotif in progress DISKDRIVE connected to the 8757 SYSTEM INTERFACE Aborts any data transfers in progress Unitnumber unchanged Volume number unchanged m ASCII or binary mode unchanged The following analyzer conditions are not changed during a PRESET IP command execution Reference position Trace memory Save Recall registers HP IB addresses Request mask Limit lines Title Detector offset User defined plot 8757 SYSTEM INTERFACE bus control on off Repeat autozero timer Display intensity Display colors Plot buffer 1 HP 8757C only Passthrough Programming commands and data may be sent to Hewlett Packard instruments connected to the 8757 SYSTEM INTER FACE and the analyzer CRT This is accomplished by first sending the PASSTHROUGH command PTd where dis the je decimal address of the device being addressed Subsequent
14. PRIOR MENU returns the previous menu DELETE YES deletes all files in the directory with the active file title If you do wish to delete the files with the active file titles press DELETE YES NO exits the delete fite menu without deleting any files If you want to delete files other than the current active file use SELECT TITLE or the file directory to change the active file title DISK UNIT shows the unit of the disk drive where the analyzer expects to find your disk When pressed DI SK UNIT appears in the active entry area of the CRT along with the unit number of the drive To change the unit number use the numeric keypad to enter the new unit number and terminate the entry with the ENT key I n ne An h neiii st AP RAP RATA NRT NT Operating Reference 45 46 RENE R MEER DISK VOLUME shows you which volume of the disk drive the analyzer will access to save and recall data When pressed DI SK VOLUME appears in ihe active entry area of the CRT along with the volume number of the drive The correct volume number is critical when using a hard disk To change the volume number use the numeric keypad to enter the new volume number and terminate the entry with the ENT key BINARY FORMAT sets the measurement and memory data format to binary Binary format pro
15. Program 2 controlling the front panel All front panel keys and most of the softkeys of the analyzer may be programmed remotely via HP IB For example you can program the scale per division reference level and reference position for each channel Program 2 listing 10 REM INCLUDE GBSETUP 20 30 15 7 40 Snak 716 50 CALL IOTIMEDUTCISC amp 10 2 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 60 CALL IOABORTCISC amp 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 70 CALL IGCLEARCISC amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 80 A IP GOSUB IODUTS 90 GOSUB PAUSE 100 A C1C0C2 GOSUB IOQUTS 110 GOSUB PAUSE 120 A SD10 GOSUB IOGQUTS 130 GOSUB PAUSE 140 A RL 10 GOSUB IO00UTS 150 GOSUB PAUSE 160 A RP4 GOSUB IODUTS 170 GOSUB PAUSE 180 A IA GOSUB IOOUTS 190 GOSUB PAUSE 200 A C0C1 SDS RP4 RL 5 GOSUB IQGUTS 210 END 220 PAUSE DO UNTIL CHR 13 230 LOCATE 25 1 PRINT Press ENTER to continue LOOP CLS 240 RETURN 250 IQOUTS CALL IODUTPUTSKSna amp A LENCA 2 260 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 270 RETURN Program 2 explanation Line10 the QuickBASIC initialization file OBSETUP Line20 Clear the computer Line30 Assign the interface select code to a variable Line40 Assign the HP IB address of the analyzer to a variable Line50 Define a system timeout of 10 seconds Perform error trapping
16. 2 13 storage 2 14 termination of devices UG 17 terminators command QRG 2 3 thru calibration 23 UG 8 KEY where X represents the page number 1 X General information 2 X Installation X Operating Reference UG X User s Guide RO X Remote Operation looseleaf page behind tab X QuickReference Guide IPG X Introductory Programming Guide for HP9000 Series 200 300 Computer IPV X Introductory Programming Guide for HP Vectra DIF X In Case of Difficulty iv HP 8757C E Index timer repeat autozero xt softkey 28 TINT softkey 16 GE sic nae il keds eae pe Re S 16 TITLE softkey 39 title dispiay define cop Sete eto Te DS 39 ligi 32cm y uet ep tee 6 on oft rre et oe 39 TITLE FILE softkey recall ides itae rhet East 48 SAVE cua ad aged mu ah da eed he 45 TITLE ON OFF softkey 39 trace format io sb ev tee Rte oes 13 points number of 1 10 13 38 transfer IPG 9 IPV 11 TRACE 1 softkey 35 TRACE 2 softkey 35 TRACE 3 softkey 35 TRACE 4 softkey 35 TRACES softkey 35 transfer speed 1 11 transmission measurements UG 18 trigger GET message QRG 6 TRC FMT SWR DB softkey 13 201 softkey see
17. 2 2 G gain compression UG 15 general source requirements see source GHz softkey 28 graphics CRT commands QRG 5 18 19 CRT print ssec 39 GRAPH COLOR softkey 37 GRAPHIC ON OFF softkey TOCA gis cendo pen dae RR 48 SAVE cursu rede eise tok Y OR IR o 45 GRAPH MONO softkey 36 graticule commands QRG 71 GREEN softkey 15 GRID softkey display sci Pheasants 15 SVSIGIT doe dee de 35 grid color 22e RI 14 UG 24 H handles rack mounting with 2 5 2 7 rack mounting without 2 5 2 6 removal 2 15 HOLD ON OFF softkey 12 horizontal resolution 4 10 14 15 HP 8757C firmware revision history 3 2 HP 8757E firmware revision history 3 3 HP IB address 2 13 44 QRG 7 cables sas le EGG 2 8 characteristics 1 11 functions 0 QRG 14 15 function select commands QRG 8 13 mnemonics QRG 1 output modes QRG 16 17 status indicators 52 HP INTERFACE BUS connector 2 8 61 pin configuration 2 9 humidity requirements 2 13 14 hue see color Hz softkey 6 eee eee 28 i identity output function QRG 6 INIT DISK softkey tecall 25 oe iet ee d a ca e E o 49 SQVO ou wars save xa erp US M pde
18. 256 ASCCMIDS Lswpr0 23 ASCCMID CLswpr0 33 Actual 0 A IL Lswpr0 Lswpr GOSUB IQOUTSP 216 218 280 The following should explain the above actions Line 212 Allocate string space large enough to hold the header portion of the HP 8360 learn string 3 bytes Line 214 Read the 3 header bytes Bytes 2 and 3 indicate the number of bytes to follow Line 216 Compute the number of bytes to follow and change Maxswpr to reflect this Line 220 Allocate string space large enough to hold the remainder of the HP 8360 learn string Line 230 Read the remainder of the HP 8360 learn string Line 280 Program the source to accept its learn string then send it For the HP 8360 the complete learn string is Lswpr0 Lswpr 21 Program 11 guided instrument setup with CRT graphics As was illustrated by program 9 it is possible to utilize the CRT of the HP 8757C E as a plotter This program goes one step further by utilizing the CRT to create a simple connec tion diagram which may be recalled by the user at any time from the front panel of the analyzer This program draws the same hypothetical connection diagram that was drawn by program 9 It blanks most of the analyzer s standard display including the graticle and all annotation except the soft keys In addition it adds one softkey under both the save and the recall hardkey menus This softkey will allow the user to toggle the state of the CRT graphics of
19. 45 48 initialization 46 49 toad from voccs EL 47 programming IPG 19 save recall commands QRG 13 SOTO tO fea ken Setting aaa Eu 44 efie esssn 45 48 unit number 45 49 VOIUme sa Sots eee 45 49 DISK DRIVE softkey 42 DISK UNIT softkey colos Reit MER WE Su 45 EE We 49 DISK VOLUME softkey S VB iy REA EE EA 46 OL MP 49 DISPLAY key 12 blanking commands QRG 14 brightness adjust 13 color adjust 15 color control commands QRG 12 dynamic range 1 8 dynamic power accuracy 1 8 trace datacommands QRG 8 KEY where X represents the page number 1 X General Information 2 X E edit limit ines oc cc s 28 EDIT SEGMENT softkey 28 801 softkey see amp TRACE POINTS 8757 system interface 1 5 2 8 41 61 4 DIF 7 ENT key er Ry 30 ENTER LIM LNS softkey 2 28 ENT OFF key MESS 30 entry ale8 i oc li rares 6 entry keys 4 30 re qe MM NUM 30 environment cocos Eo roe de PEE 2 13 Storage luu eser or rua 2 14 equipment rack 2 5 7 ERASE TITLE softkey recall toate ids eui se tA que MO d 49 SAVE oss ese aa EO 45 SYSICIN
20. Line 360 This data statement draws the DUT an amplifier Line 370 This data statement indicates the end of our plotting The X and Y values are needed here only to keep the read statement in line 160 happy Line 380 End program execution Running program 11 1 Clearthe program memory of the computer and type in the program 2 Press RUN on the computer 3 Afterthe analyzer and source are preset the CRT will be blanked except the softkeys First a grid is plotted on the CRT While this isn t neccessary for our connection diagram it does give you a good indication of where the X and Y coordinates are on the analyzer s CRT 4 Allofthelines are plotted on the analyzer s CRT These are just a sequence of MOVEs and DRAWS as specified by the data statements If brighter lines are desired draw each line twice or select different pen numbers 5 Finally the labeling is added Thelabel CONNECTION DIAGRAM is done using the analyzer CRT s internal character set The DUT label was done using the computer s character set The key differences are that while using the computer s LABEL statement is easier it also takes a lot more graphics memory than the internal character set This can become very importantif you have several labels or want to have several hookup diagrams Program 12 reading disks from the HP 8757C In many cases it may be necessary to manipulate data that was saved onto disk with the HP 8757C This
21. The cursor menu contains several useful functions that can simplify many measurement procedures thus reduce meas urement times and increase productivity These features are best illustrated in the transmission and reflection sections chapters 2 and 3 respectively The HP 8757C E also has the capability of displaying mark ers generated by the HP 8350B sweep oscillator and the HP 8340B 8341B synthesized sweepers These sources each have five independent continuously variable markers which may be adjusted via the knob step keys or data entry keyboard on the source The active marker s number is pre sented on an inverted triangle on top of the displayed traces other markers are displayed below the traces with their rep resentative marker numbers beneath the triangle The markers may be manipulated while the cursor function is on the cursor will remain active identified by a and accessable via the analyzer s front panel If the cursor is turned off the active marker s power and frequency will be presented in the mode and the frequency label areas respectively When the cursor is on the markers will be visable but without displaying any measurement data The marker s utility is enhanced by sev eral marker functions such as marker sweep MKR SWEEP and marker to center frequency MKR CF A marker dif ference function MKR A computes and displays the differ ence between two markers Step seven output results
22. nein RE NE AN E M mreta aea a M mer mmm d 180 dB 90dB 1 0 11 25 16384 0 dB 25 dBm 0 dB 0 dB 19 0 0V 1 32767 90 20dBm 180 dB 90 dB 37 0 T1125V Binary data can be unscaled using the following equation V1 V0 767 real value value X V0 Pass Through Address Set the Pass Through address of an instrument connected to the 8757 SYSTEM INTERFACE 415 a two digit ASCII integer which represents the HP IB address of the instrument to be programmed Set Cursor position to d dis a decimal integer which represents a horizontal position on the CRT witha range of values shown below No of trace points range of d 101 Oto 100 201 Oto 200 401 Oto 400 801 Oto 800 1601 0to1600 Control OT1m Rear panel control output 1 on off Outputs OT2m Rear panel control output 2 on off 1 HP 8757C only Cursor Position 14 Table 2 HP IB Only Functions 2 of 2 Sweep Hoid mode Sweep off hold HP IB bus activity until completion of TSd number of sweeps d Sweeps then hold trace data on the CRT The HP 8757C E must be in the Non Swept SWO or Sweep Hold SW2 modes before executing dis a decimal integer from 1 to 255 For certain operating modes such as SWR trace mode Alternate Sweep HP IB Action ntax Description on Averaging on or Smoothing on itis recommended that 2 successive Sweep Swo Non swep
23. 80 CALL IOTIMEQUTCISC amp 10 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 90 CALL IOABORTCISC amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR CALL IOCLEARCISC amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 110 A IP GOSUB IGOUTS 120 A PT19 GDSUB IOD0UTS 130 CALL IOLOCAL Sna amp 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR INPUT SET UP SYSTEM PRESS ENTER BS Match 102 CALL IOMATCHCISCa Match 02 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A OL GOSUB IOQUTS Actualz 0 Lsna SPACE CMaxsnaX CALL IGENTERSCSna amp Lsna MaxsnaX Actual IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A OL GOSUB IODUTSP 100 140 150 160 170 180 190 200 20 210 220 230 Actual 0 Lswpr SPACE Maxswpr CALL IGENTERSCPassthru amp Lswpr Maxswpr AciualX IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR CALL IOMATCHCISC amp Match 12 IF PCIB ERR NOERR THEN ERROR PCIB BASERR A IP GOSUB IODUTS INPUT TO RESTORE SETUP PRESS ENTER B A IL Lsna GOSUB IOQUTS A IL Lswpr GOSUB IOQUTSP A 9 GOSUB IODUTS CALL IOLGCALCSna amp 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR END 1000 5 CALL IOOUTPUTSC Sna A LENCA IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR RETURN IOQUTSP CALL IQOUTPUTS Passthrus A LENCA 22 IF PCIB ERR NOERR THEN ERROR PCIB B
24. 89 Queensway Central Hong Kong 5 8487777 Germany Hewlett Packard GmbH Vertriebzentrale Deutschland Hewlett Packard Strasse Postfach 1641 6380 Bad Homburg v d H Federal Republic of Germany 06172 400 0 France Hewlett Packard France Parc d activite du Bois Briard 2 avenue du Lac 91040 Evry Cedex 01 60 77 83 83 United Kingdom Hewlett Packard Ltd Customer Information Centre King Street Lane Winnersh Wokingham Berkshire RG11 5AR 0734 777828 Italy Hewlett Packard italiana S p A Via G di Vittorio 9 20063 Cernusco Sul Naviglio MI Milano 02 923691 European Multi Country Region Hewlett Packard S A Route du Nant d Avril 150 1217 Meyrin 2 Geneva Switzerland 41 22 83 8111 Or write to United States Hewlett Packard Company P O Box 10301 Palo Alto CA 94303 0890 Europe Middle East Africa Hewlett Packard S A Central Mailing Department P O Box 529 1180 AM Amstelveen The Netherlands For all other areas Hewlett Packard Company Intercontinental Headquarters 3495 Deer Creek Road Palo Alto CA 94304 U S A July 1 1990 Printed in U S A HP Part Number 08757 90077 HP IB Programming Note Introductory Programming Guide UJ For the HP 8757C E scalar network analyzer with the HP 9000 series 200 300 desktop computer BASIC Introduction This programming note describes the remote operation of the HP 8757C E Scalar Network Analyzer with the
25. AVG ON OFF Turns averaging on AVG FACTOR Displays current averaging factor value in active entry area default value is 8 the value may be changed via the keypad knob or step keys RESTART AVERAGE Restarts the averaging algorithm AVG ON OFF Turns off averaging function Sako SEPT et 2 lon se Sto S mer 20 09 ap Url scs ou E Pr H i JAVERAGXNG Gn salle 7 a ee AN ILL 2 NDW wp ww STAS FIL 2400 H H 1 STRT R 14 Smoothing Although smoothing does not lower the noise floor it can make noisy signals easier to interpret by reducing trace rip ple Smoothing is often likened to video filtering and is different from averaging Averaging computes each data point based on the average value during several sweeps Smoothing computes each data point based on one sweep but on the average of a window of several data points for the current sweep The window or smoothing aperture is a per cent of the swept frequency span less than or equal to 20 Use smoothing with caution too large a smoothing aperture may distort the data The trace on channel 2 shows the response of a bandpass filter with no smoothing The chan nel 1 trace shows the response with 1 smoothing For this example the 1 smoothing reduces the noise seen in the fil ter s reject band Increasing smoothing beyond 1 will vi
26. Adjust the analyzer and source to a preferred instrument state then press Continue on the computer 4 The computer will save the learn strings of both the analyzer and the source After completing this the analyzer and source will be preset to destroy your original instrument state 5 The computer stops and displays TO RESTORE SETUP PRESS CONTINUE Press Continue on the computer The computer will restore your original instrument state via the two learn strings Verify on the displays of the analyzer and the source that your instrument state has been restored This example is designed to work with the HP 8350B Sweep Oscillator which has a learn string of 90 bytes The program can be easily modified to work with the HP 8340B and 8341B Synthesized Sweepers which have learn strings 123 bytes in length To do this change the 90 in lines 20 130 and 170 to 123 17 Program 11 CRT graphics on the HP 8757C As was illustrated by program 9 it is possible to utilize the CRT of the HP 8757C E as a plotter This program goes one step further by utilizing the CRT to create a simple connec tion diagram which can be recalled by the user at any time from the front panel of the analyzer This program draws the same hypothetical connection diagram as was drawn by program 9 It blanks most of the analyzer s standard display including the graticle and all annotation except the softkeys In addition it adds one softkey
27. Central Hong Kong 5 8487777 Japan Yokogawa Hewlett Packard Ltd 29 21 Takaido Higashi 3 chome Suginami ku Tokyo 168 03 331 6111 Latin America Latin American Region Headquarters Monte Pelvoux Nbr 111 Lomas de Chapultepec 11000 Mexico D F Mexico 905 596 79 33 Data Subject to Change December 1 1990 Copyright 1989 Hewlett Packard Company Printed in U S A HP Part No 08757 90076 In Case of Difficulty CONTENTS introduction Manual Operation Line Power Problems Error Codes Table 1 Summary of Error Codes System Operation General HP IB Connections and Addresses Other Cable Connections Remote Operation inaccurate Operation Calibration Modulation Characteristics Sweep Speed Miscellaneous Problems Alternate Sweep Number of Trace Points and Memory Autozero of DC Detectors Save Recall Registers System Interface On Off Measurement Memory Memory Cursor Search On Site Service OO O1 Ct Oi 4 P P CO CO PO TO TO INTRODUCTION Use these suggestions when minor problems arise with the analyzer that do not involve defects in the analyzer s internal circuitry This includes manual system and remote operation problems cable connections and other miscellaneous problems If help for your problem cannot be found here see section 8 in the service manual Text that applies only to the HP 8757C is enclosed with these symbols In a table text that is HP
28. Color is described in terms of three parameters brightness intensity color saturation and tint hue 2 Color is used as a softkey label representing saturation a color parameter Command A set of bytes that defines a computer or instrument operation HP 8757C E Glossary 1 2 Controller 1 A device capable of specifying the talker and listeners for an information transfer 2 An external computer connected to an instrument to control its operation CPU An abbreviation for Central Processing Unit Used to refer to the A3 board or 68000 chip on the A3 board CRT An abbreviation for Cathode Ray Tube Used in this manual to refer to the display screen Cursor An electronically generated pointer which moves across the trace to identify point values CW An abbreviation for Continuous Wave Refers to a single frequency versus a swept frequency dB An abbreviation for Decibel A relative unit of measure dBm Power in decibels expressed in terms of its ratio to 1 mW of power Default A known set of conditions used by the analyzer in the absence of user defined conditions Detector A device used with the analyzer which converts a microwave signal to a 27 778 kHz signal that the analyzer can interpret Digital Of or pertaining to the class of devices or circuits in which the output varies discrete steps Dimension 1 To specify the size of an array 2 The number of array rows or columns Disk A circular magneti
29. Line 300 Line 310 Line 320 Line 330 Line 340 Line 350 Line 360 Line 370 Line 380 Line 390 Line 400 Line 410 Line 420 Line 430 Line 440 Line 450 Line 660 Line 470 Line 480 Print a prompt on the CRT Clear the screen if the loop was terminated HP IB service requests are implemented as lightpen events This statement disables any lightpen event trapping Put the analyzer into non swept mode Clear the status register of the analyzer Set the request mask to 16 bit 4 so that the analyzer will set bit 4 operation complete at the completion of the TAKE SWEEP command This is the same as in line 140 except that we will look for interrupts this time Enable the HP IB interface to detect HP IB service requests and process the interrupt as ON PEN events Line label for routine that is executed when an interrupt is detected Enable HP IB service request interrupt event trapping Command the analyzer to take 10 sweeps Line label for loop that waits for an interrupt If a service request was not detected continue looping Disable HP IB service request interrupt event trapping End program execution Line label for routine that services the interrupts Serial poll the analyzer Reading the status byte of the analyzer clears the SRQ The CLEAR STATUS CS command could also be used Perform error trapping Disable interrupt generation from the analyzer Command the analyzer to output the
30. Line60 Abort any HP IB transfers Perform error trapping Line 70 Clear the HP IB interface of the analyzer Perform error trapping Line 80 Preset the analyzer and source Line 90 Press ENTER to continue Line 100 Select channel 1 and turn it off Turn on channel 2 Line 110 Press ENTER to continue Line 120 Set the scale per division to 10 dB No terminator is needed because this is the only command in the statement Line 130 Press ENTER to continue Line 140 Set the reference level to 10 dBm Again note the absence of a terminator Line 150 Press ENTER to continue Line160 Setthe reference position line to the center of the screen graticule 4 No terminator is needed because this is the only command on the line Line170 Press ENTER to continue Line180 Program channel 2 to measure reflection input A instead of transmission input B Line190 Press ENTER to continue Line 200 There are many commands on one line with terminators Turn channel 2 off and channel 1 on COC1 Set the scale per division SD to 5 dB reference position line RP to the center of the screen and reference level RL to 5 dBm Line210 End execution Line220 Define a subroutine that waits for the ENTER key to be pressed before returning to program execution Line230 Locate and print a prompt on the CRT Clear the screen if the loop is terminated Line240 Return from the subroutine Line250 Define a subro
31. Much more often however they are caused by dirt or metallic particles being pressed into the mating plane surface either during connection or while the connector is not in use Even an apparently clean work surface may have particles on it large and hard enough to dent or scratch a connector if any pressure is applied Dents are also caused by sudden sharp metal to metal impact as occurs most often when a connector is dropped or another metal part is bumped against it Connectors that have dents anywhere on the mating plane surfaces will not make perfect contact and the raised edges will dent any connectors they are mated to Unless the damage is very slight all such connectors should be replaced Metal and Metal By Product Particles Metal and metal by product particles such as metallic salts on the connector mating plane surfaces are the most common kinds of dirt found on connectors and these particles can be extremely damag ing They are very hard and can quickly scratch or dent the gold plating on connectors they are mated to Metal and metal by product particles originate most often on the connector nut threads and if such particles are found the connector should be cleaned completely First clean and re inspect the con nector nut threads then clean the mating plane surfaces and blow the entire connector dry with compressed air Details on cleaning appear in the next section of this Microwave Connector Care Manual Particle con
32. Store data trace to disk in file Store instrument state to disk in file Store memory trace to disk in file Store normalized trace to disk in file Select softkey q 1t08 Cursor search left Store measurement into memory Store normalized data measurement memory into memory Smoothing set to d 96 of frequency span Number of points set to d d 101 201 401 801 1601 Cursor search right Cursor search value set to d Reference level step size set to d Specify custom plot according to d Save register n Non swept mode non swept operation Output rotary knob value Swept mode normal swept operation 32768 xvalue x 32767 Sweep hold mode non swept mode with HP IB Output status bytes bus hold off until completion of TSd Control output 1 on off Continuous Temperature Compensation on off Control output 2 on off Title for file Output CW value Take d sweeps then hold display Plot channel 1 trace on external plotter Step up increment Plot channel 2 trace on external plotter Write softkey label Plot channel 3 trace on external plotter Plot channel 4 trace on external plotter Plot all on external plotter System interface control on off Plot labels on external plotter Plot custom plot Plot grid on external plotter Write to channel memory Write title s is an ASCII string of up to 50 characters External detector cal viaue for detector A External detector cal value
33. Store lower limit line into memory Store upper limit line into memory 1 HP 8757C only 2 Revision 3 1 or above foran HP 8757C revision 4 1 or above foran HP 8757E 10 Table1 Function Select Commands 4 of 6 HP IB Graticule Start value for labeling x axis graticule and entry of limit lines when Start Stop System Interface control is off or no source is connected to the 8757 Labels SYSTEM INTERFACE sis a string in the following format FA value x units where x units is GZ for GHz MZ for MHz KZ for kHz HZ for Hz or blank forno units An example FA 6 55 GZ Stop value for labeling x axis graticule and entry of limit lines when System Interface control is off or no source is connected to the 8757 SYSTEM INTERFACE sis a string in the following format FB value x units where x units is described above Set the Number of Points displayed on the horizontal axis to d d is 101 201 401 801 or 1601 If source is connected to the 8757 SYSTEM INTERFACE the sweep time may change if increasing the number of points Number of Trace Points DAd Set Detector A offset to d d must be in the range of 60 to 60 dB witha maximum resolution of 0 01 dB Set Detector B offset to d d must be in the range of 60 to 60 dB witha maximum resolution of 0 01 dB Set Detector C offset to d d must bein the range of 60 to 60 dB with a maximum resol
34. TRACE POINTS Uu UPR LIM MEM softkey 28 v ventilation rets 2 13 vertical display resolution 14 VIDEO OUTPUT RGB connectors 1 11 62 video signals 1 11 62 video filtering 22 UG 14 vision color deficient 15 voltage controled device sss 11 INDUS nee eo tuas 11 UNO 2 2 sweep requirements 1 9 VON usos eR oret x 45 49 wW warranted performance WARNING softkey warning messages COO asi esate aon nn Gas rant weight se eee Pe eh es WHITE softkey write softkey label command title command to trace memory command esie t m t th v ot n Y YELLOW softkey z zero autoZero eane ed ET P334 COH SO uid ace edi ke Erde DC detector KEY where X represents the page number 1 General information 2 Installation X Operating Reference UG X User s Guide RO X Remote Operation looseleaf page behind tab QRG X QuickReference Guide IPG X Introductory Programming Guide for HP9000 Series 200 300 Computer IPV X Introductory Programming Guide for HP Vectra DIF X in Case of Difficulty HP 8757C E Index v vi
35. array read in by the Read citifile subprogram Line70 Set up a counter to determine the number of points to be printed from the data array Note that the length of the array is kept in Intvar 1 This value is returned from the Read citifile subprogram call Line80 Print the data point the REAL component and the IMAGINARY component For a scalar analyzer the imaginary components are always presumed to be zero It is illustrative here to point out that the most general means of storing data in all analyzers requires the inclusion of phase as well as magnitude data This is accomplished by storing the linear REAL and IMAGINARY components of the measurements Line90 Continue printing until the entire data array is completed Line100 Printthe name of the file just listed at the end of the listing Linell Finish the printout by printing the number of data points in the data array Line 120 Line 130 End of the main program Define a subprogram that can be used to input the data array for the file named by the user This routine is written to be modular so that it can be easily adapted for use in other programs Declare the INTEGER variables to be used in the subprogram Line 140 Line150 Dynamically allocate memory for string variables used in the subprogram Line 160 Assign an I O path name to the mass storage file of interest In this case it is the filename input by the user Line 170 Set
36. 1250 1875 Table 1 Recommended Connector Gages Connector Type Precision 7mm Gage Kit Gage Manufacturer s Part Number MMC 299 D 009 or Starrett 81 11 624 MMC 028 2 MMC 024 4 MMC 024 5 Calibration Block Aligning Pin Pin Wrench Precision 3 5mm Gage Kit 1250 1862 MMC A034B M Male Gage Female Gage MMC A034B F Calibration Block MMC 027 3 Type N Gage Kit MMC A 027A MMC Maury Microwave Corporation 8610 Helms Avenue Cucamonga California 91730 Telephone 714 987 4715 TWX 910 581 3408 Starrett L S Starrett Company Athol Massachusetts 01331 Telephone 617 249 3551 TWX 710 390 0271 Mechanical Inspection 19 Using Connector Gages Before a connector gage is used it must be inspected cleaned and zeroed Inspecting and Cleaning the Gage Inspect the connector gage and the gage calibration block carefully exactly as you have inspected the connector itself and clean or replace them if necessary Dirt on the gage or the gage calibration block will make the gage measurements of the connectors inaccurate and can transfer dirt to the connectors themselves damaging them during gaging or when the connection is made Zeroing the Gage Zero the gage by following the steps described below and shown in Figure 10 Be sure that you are using the correct connector gage and correct end of the gage calibration block for the connector be
37. BB EOT ASCH Data n 1 DD DDD DD DDD if Extended ASCII n 1 DDD DDD DDD DDD If Binary Data n BB EOI n no of points per trace ASCH Data D xDD DDD Extended ASCII n 1 DDD DDD DDD DDD fif Binary Data n BB ECT no of points per trace ASCH Data n 1 DD DDD x DD DDDiffi Extended ASCII n 1 DDD DDD DDD DDD NA Binary Data n BB EOI n no of points per trace ASCII Data DD DDD IIf Extended ASCH DDD DDD if Binary Data n BB EON Table3 Output Modes 2 of 2 HP IB pcm _ Output OE1 Outputs error status of display channel 1 or 2 Bi EOT Error OE2 One byte is output where each bit indicates Status F Outof unction N A N A I N A N A N A N A Limits Output OK Outpus keycode for the last front panel key DD if Keycode pressed Refer to table 7 for keycodes Output Knob value the value is between 32768 BIfEOI and 32767 It is reset to 0 after Negative value counterclockwise rotation positive value clockwise rotation Output 2 bytes the Status Byte 1 and the bb EOI Extendes Status Byte 2 Both bytes are then 8757C REVxx x er lf or cleared 8757E REVxx x cr lf Output Status Bytes Outputs the HP 8757C E identity string and the firmware revision
38. DAC OUT 9 40 V sss 1 11 62 HP INTERFACE BUS 2 8 61 LINE V 10 1 0 62 MODULATOR DRIVE 62 POS Z BLANK 61 STOP SWEEP 1 12 61 SWEEP IN 61 VIDEO OUTPUT RGB 1 11 62 8757 SYSTEM INTERFACE 2 8 61 connections analyzer to source 2 10 analyzer to external monitor 2 12 CONTROL 1 connector 62 CONTROL 2 connector 62 control output commands QRG 14 emt hes toes 2 13 CRT attributes 15 CRT GRAPHIC softkey lod ke wc 48 oeae wit tere S enaa 44 CAT uer roo AMI DAN Cu ald Bake 5 graphics iPG 14 18 IPV 17 21 5 graphics commands QRG 18 19 CSR FMT SWR dB softkey 20 CURSOR softkey 19 CUF SOP oo 19 DIF 8 UG 9 bandwidth 20 UG 12 commands QRG 9 format commands QRG 9 dota uoles wen ela 19 frequency 19 MAXIMUM duse dd aud 20 MINIMUM Ea 20 position commands QRG 14 programming IPG 7 IPV 8 Search Cae 20 KEY where X represents the page number 1 X General Information 2 X Installation X Operating Reference UG X User s Guide RO X Remote Operation looseleaf page behind tab QRG X Quick Reference Guide IPG X Introductory Programming Guide for HP
39. IP GOSUB IODUTS 100 AS PT19 GOSUB IODUTS 110 AS S0 GOSUB 1O0UTS 120 Freq 2 130 Freq step 1 140 AS STR CFreq GZ SF STRS CFreq step GZ GOSUB 000 5 150 A 1 GOSUB IODUTS 160 FOR 17021 170 A Qu GOSUB 1IODQUTS 180 CALL IQENTERCSna amp Vaiued IF PCIB ERR NOERR THEN ERROR PCIB BASERR 190 PRINT 1 Value dB at Freq gt 200 A UP GOSUB IODUTSP 210 Freq Freq Freq step 220 NEXT I 230 A FA20Z FB4GZ GOSUB IODUTSP 240 AS S1 GOSUB IOQUTS e50 END 260 IODUUTS CALL IOQUTPUTSCSna amp A LENCA 2 270 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 280 RETURN 290 IOQUTSP CALL IOQUTPUTS CPassthru amp A LENCA 300 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 310 RETURN 10 Program 5 explanation Line 10 Call the QuickBASIC initialization file OBSETUP Line20 Clear the computer CRT Line30 Assign the interface select code to a variable Line40 Assign the address of the analyzer to a variable Line50 Assign the passthru address of the analyzer to a variable Line60 Define a system timeout of 10 seconds Perform error trapping Line70 Abort any HP IB transfers Perform error trapping Line80 Clear the HP IB interface of the analyzer Perform error trapping Line 90 Preset the analyzer and source Line 100 Tell the analyzer which instrument is controlled through the passthru address 19 is the sou
40. LOOP A FD2 C10D GOSUB 100075 Actual 0 CALL IOENTERACSna amp SEG Ascii dat 1 Max1 ActualZ PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR CALL IOEDLCISC amp CHR C13 CHR C10 0 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A C1WM GOSUB IOQUTS CALL IOEQOLCISC amp CHRSC13 CHR C102 2 IF PCIB ERR NGERR THEN ERROR PCIB BASERR CALL IOGUTPUTACSna amp SEG Ascii dat 1 Max1 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A C1iMY GOSUB IOQUTS DU UNTIL INKEY CHR C132 LOCATE 25 1 PRINT Press ENTER to continue LOOP CLS A C1C0 C2MY GOSUB 000 5 Actual 0 A FD3 C20D GOSUB IGQUTS CALL IOENTERB Sna amp SEG Binary dat 1 Max2 Actual 13 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR CALL IOEOLCXISC amp CHR C132 CHR C102 02 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR AS C2WM GOSUB IOQUTS CALL IOEOLCISC amp CHR C13 CHR C102 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 11 350 360 370 390 400 410 420 430 440 450 CALL IODUTPUTBCSna amp SEG Binary dat z 1 Max2 10 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR DO UNTIL INKEY CHR C1352 LOCATE 25 1 PRINT Press ENTER to continue LOOP CLS FOR IX 1 TO Max1Z Binary datXCIZ 1 MOD 100 NEXT IX A C2C0 C1MY GOSUB IOGQUTS CALL IOEULCISC amp CHR C130 CHR C100 02 IF PCIB ERR NOER
41. Line 270 Line 280 Line 290 Line 300 Line 310 Line 320 Line 330 Line 340 Line 350 Command the source to set a start frequency of 2 GHz and a stop frequency of 5 GHz Set the cursor to the maximum point on channel 2 and command the analyzer to output the cursor s value and position Define the maximum number of elements to be read into an array Define the actual number of elements read Dimension an array to contain the cursor value and position Read the value and position of the cursor Perform error trapping Print the value and position of the cursor on the computer CRT Get new cursor position from the user Input should be between 0 and 400 Set the cursor to the new cursor position chosen by the user Command the analyzer to output the cursor s value and position Read the value and position of the cursor at its new position Perform error trapping Print the cursor s value and position on the computer CRT Get new cursor frequency from the user It must be within the frequency range of the sweep selected Calculate the position of the cursor from its frequency and the start and stop frequencies of the current measurement Set the cursor to the desired position Command the analyzer to output the cursor s value and position Read the cursor s value and position Perform error trapping Calculate the cursor s actual frequency from its position and the start and stop frequencies
42. Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Line 130 Line 140 Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Initialize the graphics This sets a default line type scale and clipping limits in the computer Define the analyzer CRT as the plot device and tell the computer that it is an HP GL Hewlett Packard Graphics Language device Scale the plotting area to the entire CRT The numbers are the corners of the CRT the CRT is described in the Operating Reference Define the soft clip area to maintain a clean display Erase all graphics pages Turn on graphics page 1 to ensure that the graphics start in it Set the display to monochrome default colors Select to plot with pen 9 the lowest intensity for the analyzer CRT Plot a grid on the CRT These 100 by 100 graphic units per square giving you an indication of where the X and Y coordinates are on the CRT Select to plot with pen 10 the brightest intensity for the analyzer CRT Define where to start looking for data Here we ve indicated that the data starts at the line label Graphix which is line 280 This ensures that we always start at the right data statement Define the beginning of a loop Read three items from the data statement Pen_mode is a one character string indicating whether we should move M draw D or end E the plotting X and Y are the p
43. Marker Delta Marker Sweep sweep Trigger Internal Line External Sweep Type Manual External Continuous Sweep Mode Start Stop CF AF CW Swept CW Start Stop Frequencies CF AF Frequencies CW Frequency ALC Mode Internal External Power Meter Power Sweep Power Slope RF Power On Ofi Value Display Offset HP 8350B oniy Display Multiplier e Display Update On Off e Square Wave Modulation On Off HP 83508 only o O6 o0 0 9 Oo 9 Oo o amp O9 6 ERE EM or Shift Pulse Modulation On Off HP 8340 41 e Sweep fime e Operating Reference 8757 RECALL RECALL MENUS INSTRUMENT STATE mz HP IB on HP 8757C Figure 25 RECALL Key and Recall Menus RECALL allows you to recall information previously saved in the analyzer registers When you press RECALL the message RECALL REG appears in the active entry area on the CRT Enter the register number containing the information you wish to recall using the numeric keypad No terminator is required The analyzer retrieves the information saved in that register This takes only a moment then COMPLETE appears in the active entry area The RECALL key presents a menu which allows you to recall data previously stored to disk RECALL REGISTRI provides the same recall from analyzer register function as pressing the RECALL key See the RECALL key description for details LOAD FR DISKI presents a menu
44. Pressing a softkey such as 201 in the number of trace points menu lets you change the number of trace points to that value The value set will not be changed at power on but will preset to 401 points _ PRIOR MENU returns the previous menu system menu LABELS presents the labels menu This menu lets you show or blank one or more of the labels LABELS ON OFF toggles on and off the mode labels the frequency labels and the display status line on the CRT mmm BEG TC ONLY mmm nnm E limit lines are engaged the PASS FAIL indicator will not be blanked until limit lines are disabled ee RAL note errr E M REPRE Secure Frequency Mode FRQ LBL OFF turns off the frequency labels If the frequency labels are off the source frequency readout is also blanked The frequency labels will not be plotted or printed when turned off Once off the frequency labels cannot be restored except by an instrument preset Preset turns the frequency labels on but also resets frequency information to preset conditions Power off and on does not affect the status of the frequency labels The source instrument state is still completely saved to the save recall registers even when the frequency labels are turned off However when the instrument state is recalled the frequency labels will be turned off as they were when the instrument state was saved See CLEAR SAV RCLJ for additional information Operating Referen
45. SLOPE LIMIT Sets up the slope limit function 9 25 GHz Enters start frequency of segment 44 dBm dB Enters start position of upper limit i 50 dBm dB Enters start position of lower limit 10 1 GHz Enters stop frequency of segment 1 dBm dB Terminates the upper limit line 5 dBm dB Terminates the lower limit line 19 The user may find it difficult to span the entire side of a bandpass filter with one segment since the slope is not con stant from the passband to the noise floor It may be easier to set up the limit lines for one side with two segments short ening the span or the user has the option of entering the limit lines for the entire span as two separate segments one upper and one lower To produce just an upper limit the user may select ENT for the lower limit values of the start and stop frequencies Creating point Limits POINT LIMIT Sets up the point limit function 10 4 GHz Enters the point s frequency 1 dBm dB Enters upper point position 2 dBm dB Enters lower point position i A single point limit is designated by two pointers The upper limit points down while the lower limit points up The point limits are useful for testing the response of a device at specific test frequencies Editing limit segments To edit a segment select EDIT SEGMENT from the limit line menu and enter the segment number the segment w
46. Store upper limit line into memory Display normalized data measurement memory Modulation on off Display measurement data Display the channel menu main menu Display normalized data same as M Monochrome display Marker or cursor to reference line Manual sweep mode on off Display the measurement menu Display the display menu Display the scale menu Display the reference menu Display the cursor menu Display the average menu Display the calibration menu Display the special menu Display the system menu Display memory data Manual calibration of DC detectors Non standard sweep mode on off Output cursor value Output trace data Output error status of display channel 1 Output error status of display channel 2 Output identity Output keycode of last key pressed Output learn string Output memory data Output normalized measurement data Output interrogated parameter value xx AF memory BW DA DB DC DR RL RP SD SL SO SP SR S5 ST Output rotary knob value 32768 z value 32767 Output status bytes Control output 1 on off Control output 2 on off Output CW value Plot channel 1 trace on external plotter Piot channel 2 trace on external plotter Plot channel 3 trace on external plotter Plot channel 4 trace on external plotter Piot all on external plotter System interface control on off Plot labels on external plotter Plot custom plot Plot grid on external plotter
47. The HP 8757C E Scalar Network Analyzer accepts specific programming commands for selecting front panel key func tions most softkey functions and special HP IB only functions Line switch control and HP IB address setting are not programmable The analyzer can pass through HP IB commands to a compatible Hewlett Packard swept source graphics plotter and printer connected to the 8757 SYSTEM INTERFACE A list of compatible instruments is given in 8757 System Interface In addition some Hewlett Packard Graphics Language HP GL commands may be passed through to the CRT Programming data consists of a string of ASCII coded charac ters composed of one or more of the following control fields Select channel Measure power ratio Display measured data memory Select scale Select reference value position Inputsyntax 1 function code function code Select averaging Cursor functions Plot functions HP GL graphics commands Instrument state registers Special HP IB only functions Input syntax The analyzer responds to program commands in the order in which they are received The commands can be upper or lower case ASCII characters and must be sent without any intervening alphanumeric characters or digits spaces are ignored There are two input command terminators which can be uni versally applied to all analyzer input commands a line feed 10 or a semicolon It is best to terminate all input pro gramming comman
48. To engage a softkey function press the key to the immediate right of the softkey label on the CRT LINE This switch controls AC power to the analyzer HP 8757C E CRT DESCRIPTION The analyzer CRT is divided into several information areas See figure 2 PISS IN IS INTE eee Figure 2 The Analyzer CRT 1 MODE LABELS For each channel that is turned on this area shows the measurement mode single input or ratio status symbols indicating activated functions cursor amplitude or HP 8350B or 8340 8341 series active marker amplitude scale per division and reference leve value Figure 3 shows each part of the mode labels area Measurement Status Symbols Cursor or Marker Value CH1 A M SA 28 50 dBm 10 0 dB REF 0 00 dBm Scale per Division Reference Level Value Figure 3 Mode Labels Description Status Symbols These symbols identify engaged functions See table 1 for a list of these symbols Read about the functions they representin Front Panel Operation The associated FUNCTION or INSTRUMENT STATE key will help you locate each function HP 8757C E Operating Reference PN VOTES Table 1 Status Symbol Identification Status Function Key Symbol Activated Feature Instrument State Key MEASUREMENT MINUS MEMORY DISPLAY MEM MEMORY DISPLAY AVERAGING ON AVG SMOOTHING ON SPCL ADAPTIVE NORMALIZATION ON SYSTEM ADAPTIVE NORMA
49. WK1 CAL 1 GOSUB IODUTS PCIB BASERR 120 A 2 TESTI GOSUB IODUTS 440 RETURN 130 A WKZ CAL2 GOSUB IOOUTS 140 AS WK4 TEST2 GOSUB 000 5 150 A WKS ABORT GOSUB IDDUTS 160 PRINT SOFT KEYS LOADED 170 CALL IOPENCIsca 0 180 ON PEN GOSUB Srq recv 190 PEN ON Program 8 explanation Line 10 Line 20 Line 30 Line 40 Line 50 Line 60 Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Line 130 Line 140 Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260 Line 270 Call the QuickBASIC initialization file QBSETUP Clear the computer CRT Assign the interface select code to a variable Assign the address of the analyzer to a variable Define a system timeout of 10 seconds Perform error trapping Abort any HP IB transfers Perform error trapping Clear the HP IB interface of the analyzer Perform error trapping HP IB service requests are implemented as lightpen events This statement disables any lightpen event trapping Preset the analyzer and source Set the request mask to 8 bit 3 See table 1 for the description of the status bytes Label softkey 1 with CAL 1 Softkey 1is the softkey at the top of the CRT Label softkey 2 with TEST 1 Label softkey 3 with CAL 2 Label softkey 4 with TEST 2 Label softkey 8 with ABORT Print a message to the user Enable the
50. addressing of the 8757 SYSTEM INTERFACE address will pass through commands to the selected device The PTd command may be sent at any time The default addresses for PASSTHROUGH commands are as follows HP 8757C E Analyzer 16 decimal 8757 SYSTEM INTERFACE 17 decimal HP 8757C E CRT 15 decimal Hewlett Packard Source 19 decimal Hewlett Packard Plotter 05 decimal Hewlett Packard Printer 01 decimal Hewlett Packard Disk Drive 00 decimal The following section explains how to pass through com mands to instruments connected to the 8757 SYSTEM INTERFACE and the analyzer CRT 8757 SYSTEM INTERFACE This rear panel connector is physically similar to the HP IB port but is specifically used to control the following instruments Sources HP 8350B Sweep Oscillator HP 8340B Synthesized Sweeper HP 8341B Synthesized Sweeper HP 8360 Series Synthesized Sweeper Plotters HP 7470A Two pen Plotter HP 7475 A Six pen Plotter HP 7550A Eight pen Plotter Printers HP 2225A Think et Printer HP 3630A PaintJet Printer HP 2227B QuietJet Plus Printer Disk Drives HP 9122 Dual 3 5 in Disk Drive The transfer of commands and data is performed by first sending a PASSTHROUGH command PTd to the analyzer where d is the decimal address of the desired device Subse quent addressing of the 8757 SYSTEM INTERFACE will pass through commands to the instrument selected The address of the 8757 SYSTEM INTERFACE is determined by complementing the least significan
51. and the labels At the end of the DISPLAY key and menu description is additional information about color definitions and adjustments HOLD ON OFF freezes the active channel measurement data the CRT MEAS shows the measurement data of the selected input or ratio of inputs MEM shows the measurement data that had previously been stored in the memory of that channel When this function is engaged appears in the status symbols section of the mode labels area for that channel Operating Reference HP 8757C E MEAS MEM is used to subtract the data previously stored in memory from the current measurement data This is commonly used during calibration to produce a normalized trace When engaged appears in the status symbols section of the mode labels area for that channel TRC FMT SWR dB provides a choice of data formats for reflection data as standing wave ratio SWR or as return loss dB The data is formatted as return loss at preset HP 87876 ONLY n The SWR selection is available only for ratioed or normalized measurements on channels 1 and 2 with 401 or fewer points Channels 3 and 4 must be turned off to engage SWR format on channels 1 and 2 SWR is calculated using a lookup table that is generated when SWR format is selected This initial caiculation takes a few moments but the data is shown in real time thereafter BRTNESS ailows you
52. the device under test will be connected and press STORE THRU The message THRU SAVED IN CH1 MEM appears on the CRT The first calibration menu is automatically presented Now the message For Normalized Meas select DISPLAY MEAS MEM appears on the CRT if you were not already in MEAS MEM mode Press these keys to normalize the measurement MEAS MEM stores the current measured data into memory The data is stored in dB dBm format even when you are viewing the data in SWR format This softkey is also part of the DISPLAY menu MEAS M MEM stores the measurement minus memory normalized trace into memory This func tion can be used for ratio measurements only This softkey is also part of the DISPLAY menu DC DET ZERO appears in the calibration menu only when AC DC detectors or bridges are connected to the detector inputs Pressing DC DET ZERO presents the DC detector zero menu Use these softkeys to zero DC detectors Zeroing eliminates small DC voltages present in the detectors and establishes the noise floor with no RF signal applied Periodic zeroing also compensates for the effects of DC drift Zero your DC detectors when you first connect them to the analyzer before calibration and whenever significant temperature changes occur HP 8757C E Operating Reference 23 MANUAL is used when you must manually remove the RF signal from the detectors Use this method of zeroing with sources not connected to the anal
53. 0 0 GOSUB IODUTSP 310 END 320 IOQUTS CALL IODUTPUTS CSna amp A LENCA 330 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 340 RETURN 350 IOQUTSP CALL IOGUTPUTS Passthru amp A LENCA 360 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 370 RETURN DIAGRAM DUT Figure2 The CRT Graphics Display 18 Program 9 explanation Line10 the QuickBASIC initialization file QBSETUP Line 20 Clear the computer CRT Line 30 Assign the interface select code to a variable Line 40 Assign the address of the analyzer to a variable Line 50 Assign the passthru address of the analyzer to a variable Line60 Define system timeout of 10 seconds Perform error trapping Line70 Abort any HP IB transfers Perform error trapping Line80 Clear the HP IB interface of the analyzer Perform error trapping Line90 Preset the analyzer and blank the CRT display Define the CRT graphics as the target of passthru commands The graphics address is always one less than the analyzer s HP IB address Line100 Erase all graphics pages Turn on graphics page 1 to ensure that the graphics start in it Set the color selection to default monochrome colors Line110 Select to plot with pen 9 the lowest intensity for the analyzer CRT Line120 Repeat a loop 29 times to draw part of the grid Line130 Draw a vertical line down the CRT Line140 End of the loop Line 150 Repeat loop 20 times to draw the horizontal part of the grid
54. 260 Command the analyzer to output the channel 1 data trace Line 270 Read the channel 1 trace Line 280 Return the analyzer to swept mode The analyzer display begins updating continuously Line290 of execution Running program 7 1 Clearthe program memory of the computer and type in the program 2 Press RUN on the computer 3 The computer first presets the analyzer and source It then sets the source to 250 milliseconds per sweep and sets the analyzer to display transmission on channel 1 4 Thecomputer commands the analyzer to take 10 sweeps and polls the analyzer status byte to determine when they were completed The computer reads a trace from the analyzer Just before the trace is sent you should see the display freeze as the TAKE SWEEP command is completed 5 Press Continue and the computer again tells the analyzer to take 10 sweeps This time the computer receives an interrupt after the last sweep The computer sits in a loop line 220 and waits until the analyzer signals completion of the TAKE SWEEP command In this segment of the program you should not see the display freeze at all Immediately after it receives the interrupt the computer puts the analyzer back into swept mode This method of sensing the end of a TAKE SWEEP command via an interrupt is more time efficient than the polling method previously used because the computer can be doing something else during the 10 sweeps T
55. 40 Snak 716 50 Passthru 717 60 CALL IOTIMEQUTCISC amp 101 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 70 CALL IGABORTCISCa gt IF PCIB ERR NOERR THEN ERROR PCIB BASERR 80 CALL IOCLEARCISC amp 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 90 A IP BLS PT15 GOSUB IODUTS 100 A EP GP1 1 DF GOSUB IODUTSP CONNECTION 110 A SP 9 GOSUB 000 120 FOR Col 0 TO 29 130 A PU PA STR CCol 100 0 PD PA STR CCol 100 2000 GOSUB IOQUTSP 140 NEXT Col 150 FOR Row 0 TO 20 160 AS PU PA 0 STR CRow 100 PD PA 2900 STRSCRow 100 GOSUB IODUTSP 170 NEXT Row 180 A SP 1 GGSUB 000 190 A PA 600 1600 PD 00508 IODUTSP 200 A SI10 28 0 34 LBCONNECTION DIAGRAM CHR C32 GOSUB IOQUTSP 210 A PU PA 1200 250 GOSUB IODUTSP 220 A 510 28 0 34 LBDUT CHR 3 GOSUB IODUTSP 230 A PU PA 300 800 PD PA 1100 800 1100 1100 300 1100 300 800 GDSUB IQOUTSP 240 A PU 800 800 PD PA 800 1100 GOSUB IQQUTSP 250 A PU PA 1500 800 PD PA 2300 800 2300 1200 1500 1200 1500 800 GOSUB IODUTSP 260 A PU PA 1950 800 PD PA 1950 1200 GOSUB IOQUTSP 270 PU PA 875 850 PD PA 875 500 1200 500 GOSUB IGQUTSP 280 AS PU PA 1400 500 PD PA 2050 500 2050 850 GOSUB 000 5 290 A PU PA 1200 400 PD PA 1400 500 1200 600 1200 400 GOSUB IODUTSP 300 A PU PA
56. 46 initialization of disk 46 49 insertion losS UG 12 INSPECTION 2 1 INSTRM STATE softkey recall ois cl Lose X RR 48 8V xml yum EA Nasa gs 44 instrument preset QRG 3 command 2 6 0 eee ee QRG 12 INSTRUMENT STATE keys 4 31 interconnections analyzer to source 2 10 analyzer to external monitor 2 12 internal calibration tables 25 Instailation X Operating Reference UG X User s Guide RO X Remote Operation looseleaf page behind tab QRG X QuickReference Guide IPG X Introductory Programming Guide for HP9000 Series 200 300 Computer IPV X Introductory Programming Guide for HP Vectra DIF X ii HP 8757C E in Case of Difficulty Index interrogate output data function QRG 5 K keycodes front panel QRG 21 keypad 30 keys CHANNEL 4 8 9 ENTRY ios D de he RN S 4 33 front panel ess 4 10 FUNCTION 4 10 INSTRUMENT STATE 4 34 4 softkey menus 54 60 STEP 30 kHz softkey 28 knOD ore even YS 30 L LABELS softkey display SS 15 SyStom 38 labeis blanking 38 ARG 7 UG 24 ole arse cuve 14 UG 24 frequency 6 mode volere e RU SERE 5 SOflKGy uoce he
57. 7mm CONNECTORS 42 SMA Compatible Adapters for HP 85021 27 series Directional Bridges 42 HP 85130A Special Adapter Kit 42 Type N Connectors 45 750 Type N Connectors 45 MECHANICAL SPECIFICATIONS OF TYPE N CONNECTORS 46 Electrical Effects of Contact Separation 48 Gaging Type N Connectors 49 Male Type N Connectors 49 Female Type N Connectors 52 Connection Technique 52 SMA and Precision 3 5mm APC 3 5 Connectors 53 SMA CONNECTORS 53 SMA Connector Problems 54 Dielectric Protrusion 54 Out of Specification SMA Male Pins 54 Precision 3 5mm Connectors 56 Contents i MATING SMA AND PRECISION CLEANING SMA AND PRECISION 3 5mm CONNECTORS 58 3 5mm CONNECTORS 66 Electrical Performance 60 Cleaning Solvents 66 ANADISIS Xo odi reek Se Edu ae 61 GAGING SMA AND PRECISION 3 5mm to 3 5mm or SMA Adapters 61 3 5mm CONNECTORS 67 7mm to 3 5mm SMA Adapters 61 Male SMA and Precision HP 85021 27 series Directional Bridges 64 3 5mm Connectors 67 Special 3 5mm F to Precision Female SMA and Precision 7mm Adapters 65 3 5mm Connectors 67 ILLUSTRATIONS PART ONE PRINC
58. 7mm connectors contact between the center conductors is made by spring loaded contacts called collets These protrude slightly in front of the outer conductor mating plane when the connectors are apart When the connection is tightened the collets are compressed into the same plane as the outer conductors For this reason two mechanical specifications are generally given for precision 7mm connectors the maximum and minimum recession of the center conductor behind the outer conductor mating plane with the center conductor collet removed aminimum and maximum allowable protrusion of the center conductor collet in front of the outer conductor mating plane with the collet in place The critical mechanical specification is the recession setback of the center conductor relative to the outer conductor mating plane with the center conductor collet removed No protrusion of the center conductor in front of the outer conductor mating plane is ever allowable and sometimes a minimum recession is required Consult the mechanical specifications provided with the connector or the device itself The center conductor collet should also spring back immediately when pressed with a blunt plastic rod or with the rounded plastic handle of the collet removing tool Nominal specifications for precision 7mm connectors exist But the allowable tolerances and some times the dimensions themselves differ from manufacturer to manufacturer and from device to d
59. 9000 Series 200 300 Computer IPV X Introductory Programming Guide for HP Vectra DIF X In Case of Difficulty HP 8757C E Index i CURSOR REF LEVEL softkey 20 CURSOR ON OFF softkey 19 CURSOR A ON OFF softkey 19 OFF 41 D DAC OUT 0 10 V connector 1 11 62 damaged analyzer see inspection data display area 6 data output QRG 5 dBm dB key 30 DC DET ZERO softkey 23 DEFAULT COLORS softkey 15 DEFINE CUSTOM softkey 35 DELETE ALL LNS softkey 28 DELETE FILE softkey recall soeur ERIS 49 SB8VB isle picks iu leur E cag 45 DELETE SEGMENT softkey 28 detection AC and DC 1 5 39 UG 25 detector adapter 25 DOS ZOO usen vy RES US 23 DC zero commands QRG 9 mode commands QRG 11 external calibration 25 INPUTS uoo co Euro m er 53 Offset uuo iz WEAR 24 offset commands QRG 11 power calibration 25 DET A softkey 24 DET B softkey 24 DET C softkey 24 DET R softkey 24 DET OFFSET softkey 24 DET PWR CAL softkey 25 dimensions 1 12 disle clu Boek ene etm dais UG 22 delete file 45 49 file directory
60. Abort plot if in progress Disk drive e Aborts any data transfers in progess e Unit number unchanged Volume number unchanged e ASCII or binary mode unchanged The following analyzer conditions are not changed during a PRESET IP command execution Reference position Trace memory Save Recail registers HP IB addresses Request mask Limit lines Title Detector offset User defined plot 8757 System Interface control on off Repeat autozero timer Display intensity Display colors e o 9 G e 9 5 9 9 9 Program 1 listing 10 ASSIGN Sna TO 716 20 ABORT7 30 CLEAR Sna 40 REMOTE Sna 50 PAUSE 60 REMOTE Sna 70 LOCAL LOCKOUT 7 80 PAUSE 90 LOCAL 100 PAUSE 110 OUTPUT Sna IP 120 END Program 1 explanation Line10 Assign the address of the HP 8757C E toan1 O path This is not required but it is good program ming practice If you change the address of the instrument later you only change the address in one place in your program i HP 8757 only 2 HP 8757C Option 001 only Line20 Abort any HP IB transfers and reset the computer s HP IB interface Line30 Clear the analyzer s HP IB interface Line 40 Set the analyzer and source to remote mode Line50 Temporarily stop execution Line 60 Setthe analyzer and source to remote mode Line70 Lock out the LOCAL key of the analyzer and source Line 80 Temporarily stop execution Line90 Set the analyzer and
61. Command the analyzer to return to swept mode The analyzer again updates the trace information on the display This command also exits passthru mode Line 240 Line 250 Line 260 End program execution Define a subroutine that outputs commands to the analyzer Line 270 Line 280 Line 290 Perform error trapping Return from the subroutine Define a subroutine that outputs commands to the source through the passthru address of the analyzer Line 300 Line 310 Perform error trapping Return from the subroutine Running program 5 1 Clear the computer CRT and type in the program 2 Press ALT R S on the computer 3 Thesource frequency is set immediately to 2 GHz and the computer begins reading reflection input A of the analyzer and printing the measurements After 21 readings the program ends Program 6 trace transfer One feature that sets the HP 8757C E apart is its ability to transfer an entire measurement trace to a computer at very high speed A complete high resolution 0 01 dB 401 point measurement can be sent to the computer in 35 milliseconds binary format or 800 milliseconds ASCII format Transfer time will be less for fewer points per trace and greater for more points per trace The analyzer gives you complete flexibility when reading measurement traces via HP IB You can read from the active channel and you can read the stored memory trace the cur rent measurement trace or the nor
62. Compatibility 1 7 User s Guide Recommended Test Equipment 1 7 INWOGUCWOR rss ses REPOS 3 Operating the HP 8757C E 5 SECTION 2 INSTALLATION CRISDISDIBM 3 deren a cw ei Pek eee Wad 2 1 ren poeta rea eg Initial Inspection 2 1 Sess on cuim 2 Preparation For Use 2 2 gets Power Requirements 2 2 instrument State Selection 6 Line Voltage and Fuse Selection 2 2 Genera MASSU AMIS oct Power Cable 2 3 Transmission Moasuramenis ea A Rack Mounting 2 5 Basic System Configuration 11 Rack Mounting without Front Handles Opt 908 2 5 BANOR LORS utputa se 2 Rack Mounting with Front Handles Opt 913 2 5 Aan ae Pa MM M NM AO ME is HP Interface Bus and 8757 System Interface pud Ups VE RUNNERS testi YT a dod Connectors and Cables uuu 2 8 Out of Band Rejection FEN EA REB edd ede Eh euet 13 Analyzer to Source Interconnections 2 10 nc E UIS USES BORSE RUE i Be Go eid ii Achaea MD ae Reflection Measurements with the HP 8757C E 17 Analyzer to External Monitor Interconnections 2 12 Signal Separation QE ML ey ON ge af HP IB Address Selection
63. DISK softkey Note the GRAPHIC ON OFF softkey it does not appear unless the BLA command is used Press the GRAPHIC ON OFF softkey so that it is off The connection diagram will now disappear from the CRT display Press the GRAPHIC ON OF softkey again and the diagram will reappear If you store this setup to the external disk drive at this time the analyzer will remember this graphics on off mode later upon recall from disk 23 Table 2 Alphabetical Listing of HP 8757C E Programming Codes 1 of 2 Averaging off A B ratio measurement A C ratio measurement Averaging on and factor d Adaptive Normalization on off A R ratio measurement Autoscale Autozero repeat on off of the DC detectors Autozero the DC detectors once B A ratio measurement B C ratio measurement Plotter buffer on off Restore CRT to normal mode Blank frequency labels secure mode frequency labels cannot be restore Blank all labels Blank active channel trace Blank softkey labels Blank all except user CRT graphics Blank title Blank mode labels Blank the active entry area Blank the limit lines Blank all except user CRT graphics and softkeys B R ratio measurement Overall display brightness Display the search bandwidth on the CRT Channel off Channel 1 on active Channel 2 on active Channel 3 on active Channel 4 on active C A ratio measurement C B ratio measurement Set chann
64. HP 9000 Series 200 300 desktop computer used as a controller This includes the PC 308 which features an HP Vectra PC and the HP 82300B HP BASIC Language Processor Card Included in this guide are several short programs that demonstrate the use of the analyzer with HP IB commands and a diagram of system connections for remote control The HP 8757C E is a fully programmable analyzer capable of making magnitude only transmission and reflection measurements over an RF and microwave frequency range of 10 MHz to 100 GHz When used with an HP IB computer the analyzer s front panel may be remotely controlled along with most softkey functions and some functions accessible only via HP IB The analyzer exerts control over a source HP 8350B or HP 8340B 41B digital plotter HP 7440A or HP 7550A and printer HP 2225A ThinkJet HP 3630A Paintjet or HP 2227B Quietljet Plus connected to the 8757 SYSTEM INTERFACE This note assumes you are familiar with local non remote operation of the HP 8757C E If not refer to the operating manual You should also be familiar with the HP 9000 j Series 200 300 computer particularly HP IB operation Throughout the rest of this document the term computer refers to any of these computers ARS PU S 2 SEVEN OA Oe es o EN SE V x oO Reference information The following texts provide additional information on the HP Interface Bus the analyzer
65. Hewlett Packard Asia Ltd 22 F Bond Centre West Tower 89 Queensway Central Hong Kong 5 8487777 Japan Yokogawa Hewlett Packard Ltd 29 21 Takaido Higashi 3 chome Suginami ku Tokyo 168 03 331 6111 Latin America Latin American Region Headquarters Monte Pelvoux Nbr 111 Lomas de Chapultepec 11000 Mexico D F Mexico 905 596 79 33 Data Subject to Change December 1 1988 Copyright 1988 Hewlett Packard Company Printed in ULS A HP Part No 08757 90075 HP IB Programming Note Introductory Programming Guide HEWLETT PACKARD U For the HP 8757C E scalar network analyzer with the HP Vectra Personal Computer using Microsoft QuickBASIC 4 5 Introduction This programming note describes the remote operation of the HP 8757C E Scalar Network Analyzer with the HP Vectra Personal Computer or IBM compatible using the HP 82335A HP IB Command Library and Microsoft QuickBASIC 4 5 Included in this guide are several short programs that demonstrate the use of the analyzer with HP IB commands and a diagram of system connections for remote control The HP 8757C E is a fully programmable analyzer capable of making magnitude only transmission and reflection measurements over an RF and microwave frequency range of 10 MHz to 100 GHz When used with an HP IB compu ter the analyzer s front panel may be remotely controlled along with most softkey functions and some functions accessible only via
66. IN 5 2 5 1 0 5 0 25 0 1 0 05 and 0 025 voits per division HP 8757C E Operating Reference 18 REF REFERENCE MENUS FUNCTION HP 8757C E Figure 12 REF Key and Reference Menus The REF key engages the REF LEVEL function and presents the reference menu REF LEVEL lets you setthe value of the reference level line This is the horizontal line indicated by the reference position indicator on the left side of the CRT Varying the value of this line and the scale per division allows easy measurement of any data point and viewing of the measurement data relative to the reference level line value Use the knob STEP keys or numeric keypad to enter the reference level Terminate your entry with the dBm dB or ENT key REF POSN sets the position of the reference level line to any of the major graticules using the knob or the step keys The channel number and a gt symbol show the current position of each channel s reference level line REF STP SIZE sets the size of the steps used to increment or decrement the reference level value The reference step size can be set with the numeric keypad only Terminate your entry with the dBm dB or ENT key Operating Reference HP 8757C E CURSOR CURSOR MENUS FUNCTION Figure 13 CURSOR Key and Cursor Menus HP 8757C HP 8757E The CURSOR key presents the cursor menu and engages the cursor V onall channels The cursor is
67. Line 160 Draw a horizontal line across the CRT Line 170 of the loop Line 180 Select to plot with pen 1 the brightest intensity for the analyzer CRT Line 190 Move the pen to title the display Line 200 Specify the width and height of each character indicate what the title is terminate the title with an end of text character Line 210 Move the pen to label the DUT Line 220 Specify the width and height of each character indicate what the title is terminate the title with an end of text character Line 230 Move the pen and draw the outline of the source Line 240 Draw the plug in of the source Line 250 Move the pen and draw the outline of the analyzer Line260 Draw the CRT of the analyzer Line270 Draw the connections from the source to the DUT Line280 Draw the connections from the DUT to the analyzer Line290 Draw the DUT an amplifier Line300 Move to the bottom left corner of the CRT Line310 End program execution Line320 Define a subroutine that outputs commands to the analyzer Line330 Perform error trapping Line340 Return from the subroutine Line350 Define a subroutine that addresses the analyzer as a plotter Line 360 Perform error trapping Line370 Return from the subroutine Running program 9 1 Clearthe computer CRT and type in the program 2 Press ALT R S on the computer 3 After the analyzer and source are preset the CRT will be blanked First a grid is plotted on the CRT
68. Print all to monochrome except softkeys and CRT graphics Print tabular display data in monochrome Print tabular marker cursor data to external printer Print all to color printer except softkeys and CRT graphics Passthrough address set to d R A ratio measurement R B ratio measurement R C ratio measurement Recall register n Reference level set to d Service request mask set to d Reference position set to vertical division q Restart averaging Set cursor to horizontal position d Scale per division set to d Store all instrument information to disk in file Store CRT graphics to disk in file Store data trace to disk in file Store instrument state to disk in file Store memory trace to disk in file Selectsoftkey q q 1 to 8 Cursor search left Store measurement into memory Store normalized data measurement memory into memory Smoothing set to d of frequency span Number of points set to d d 101 201 401 801 1601 Cursor search right Cursor search value set to d Reference level step size set to d Specify custom plot according to d Save register n Non swept mode non swept operation Swept mode normal swept operation Sweep hold mode non swept mode with HP IB bus hold off until completion of TSd Continuous Temperature Compensation on off Title for file Take d sweeps then hold display Step up increment Write softkey label Write to channel memory Write title s is an A
69. active file title Make sure that the files you wish to delete are active You have two options DELETE YES deletes all files in the directory with the active file title If you do wish to delete the files with the active file titles press DELETE YES NO exits the delete file menu without deleting any files If vou wantto delete files other than the current active file use SELECT TITLE or the file directory to cnange the active file title ISET UP DISK presents another menu that lets you set disk unit and volume numbers initialize disks and define the format in which to save the data DISK UNIT shows the unit of the disk drive where the analyzer ts to find your disk When pressed DISK UNIT appears in the active entry area of the CRT along with the unit number of the drive To change the unit number use the numeric Keypad to enter the new unit number and terminate the entry with the ENT key DISK VOLUME shows you which volume of the disk drive the analyzer will access to save and recall data When pressed DISK VOLUME appears in the active entry area of ihe CRT along with the volume number of the drive To change the volume number use the numeric keypad to enter the new volume number and terminate the entry with the ENT key BINARY ets the measurement and memory data format to binary Binary format provides the fastest transfer speed of data and uses the smallest storage space of tne two formats available
70. and cannot be altered Limit lines and PASS FAIL indicators are included in both mono and color prints Ly ree Atm rir ama mA nan y amman Hunan rtr Putas ma t rar miren Graphics written to the CRT through HP IB are not drawn to the printer The printer can be accessed with passthrough commands which are described in Remote Operation PRINT DATA causes the printer to list all data in tabular form An example of a printout is shown in figure 22a The number of data points listed is the number selected by TRACE POINTS in the system menu PRINT MKRS causes the printer to list the data at the frequencies of the source markers that are turned on The markers are indicated by their number except for the active marker which is labeled act If the cursor is on the cursor amplitude value and frequency are also printed An example of a marker printout is shown in figure 22b Frequency Chan t Chan Z No Hz dBm dBm 1 07 s 3 381 57 017 1 2 4878E407 3 187 55 555 markara 2 3 995 07 ET 5 5 492501 07 3 141 58 741 Nias te canes prit 4 98 07 dE onn 1 2 920125E408 12 122 2 570 5 8 487501 07 3 218 54 775 2 3 7898576E408 12 207 1 894 9 985003E 07 3 248 59 310 act 2 211325E 09 14 600 2 886 7 1 14825E 08 3 248 54 759 8 1 298 08 3 188 85 098 m 1 971725 09 14 548 2 701 1 4 5975E 08 A 25208
71. as shown z OL aco uL dg gt a Averaging 2 4 8 16 32 64 128 or 256 successive traces may be averaged Smoothing Provides a linear moving average of adjacent data points The smoothing aperture defines the trace width number of data points to be averaged and ranges from 0 1 to 20 of the trace width Normalization Traces are stored and normalized with the highest resolution independent of display scale division or offset Calibration data can be saved and recalled with the instrument states Calibration data is interpolated when the frequency span is decreased with adaptive normalization engaged 1 HP 8757C only 2 0 01 dB for display cursor HP 8757C E i General Information Table 1 2 Supplemental Performance Characteristics 2 of 3 Graticules 8 vertical x 10 horizontal divisions 1 division approximately 11 mm CRT AND GRAPHICS CHARACTERISTICS CRT Scan Rate Raster scan with 60 Hz vertical refresh rate and 25 5 kHz horizontal scan rate Graphics Resolution 1024 horizontal by 400 vertical pixels REAR PANEL CONNECTORS Stop Sweep Used with the HP 8350B Sweep Oscillator and the HP 8340 or 8341 series Synthesized Sweeper whenitis controlled by the 8757 system interface to stop the sweep at band crossings and at end of sweep DAC Out An output connector for use in troubleshooting ADC IN An input connector for auxiliary voltage input in the 10 to 10 voit range Th
72. away from the connector and purge the liquid from the plastic tube with more vapor When the tube is empty spray the connector with vapor from a distance of about 6 inches 15 cm to evaporate any condensation Then allow the connector to return to normal room temperature before using it If the bead has cracked or shifted position the connector will have to be repaired or replaced Cleanina Cleaning Solvents Use solvents only in well ventilated areas Avoid prolonged breathing of solvent Vapors and con tact of solvents with the skin Dirt and stubborn contaminants that cannot be removed with compressed air can often be removed with a cotton swab HP Part Number 8520 0023 or lint free cleaning cloth HP Part Number 9310 4242 moistened with a solvent Use the least amount of solvent possible and avoid wetting any plastic parts in the connectors with the solvent Recommended Solvents Generally pure liquid Freon trichlorotrifluoroethane available as HP Part Number 8500 1251 is the best solvent for cleaning microwave connectors It is chemically inert and evaporates cleanly without leaving a residue or film Very dirty connectors can be cleaned with isopropanol Be aware that isopropanol quickly absorbs water from the atmosphere however Water applied to connectors even in this way takes a long time to evaporate and until it evaporates may result in a loss of measurement repeatability Use at least 92 per cent isopropanol and a v
73. be monitored carefully No Type N connector should ever be used when there is any possibility of interference between the shoulder of the male contact pin and the tip of the female contact fingers when the connectors are mated practice this means that no Type N connector pair should be mated when the separa tion between the tip of the female contact fingers and the shouider of the male contact pin could be less than zero when the connectors are mated Gage Type N connectors carefully to avoid damage 750 Type N Connectors 750 Type N connectors differ from 500 Type N connectors most significantly in that the center conductor male contact pin and female contact hole are all smaller Therefore mating any male 50Q Type N connector with a female 75Q Type N connector will destroy the female 75Q connector by spreading the female contact fingers apart permanently or even break ing them if both 75Q and 50Q Type N connectors are among those on the devices you are using mark the 750 Type N connectors to be sure that they are never mated with any 5002 Type N connectors TYPE N CONNECTORS MALE FEMALE mS CONDUCTOR MATING PLANE RECESSION OF OUTER PROTRUSION MALE CONTACT CONDUCTOR OF FEMALE PIN SHOULDER MATING CONTACT PLANE FINGERS Figure 7 Type N Connectors Mechanical Inspection SMA and Precision 3 5mm Connectors Because of their smaller size SMA and precision 3 5mm connector
74. binary bytes that does not end with a cr If since this could actually be part of the learn string information Program the analyzer to output its learn string Initialize the variable specifying the number of elements actually read Allocate string space large enough to hold the learn string of the analyzer 150 bytes Read the analyzer learn string into the string Lsna Program the source to output its learn string Initialize the variable specifying the number of elements actually read Allocate string space large enough to hold the learn string of the source Read the source learn string into the string Lswpr The computer must read the entire source learn string which for the HP 8350B Sweep Oscillator is 90 bytes long Enable character matching this results in termination on a linefeed when a string is read Preset the analyzer and source to clear the instrument states Prompt the user then wait for the ENTER key to be pressed Program the analyzer to accept its learn string then send it Program the source to accept its learn string then send it Re address the analyzer to exit passthru mode and continue sweeping Set the analyzer and source to local mode End program execution Define a subroutne that outputs commands to the analyzer Perform error trapping Return from the subroutine Define a subroutine that outputs commands to the source through the passthru address of the
75. binary and ASCH The format chosen is highlighted and underlined The analyzer presets to binary format ASCH FOR MAS sets the measurement and memory data format to ASCH ASCH format makes the stored data compatible with other computers INIT DISK lets you initialize a disk The analyzer will initialize the disk identified by DISK UNIT and DISK VOLUME Be certain these are correctly set before continuing INIT YESI begins iuh dn d The message WAITING FOR DISK appears on the CRT When this message is removed and disk drive light turns out initialization is complete NOTE Hf your disk is write protected the message WARNING DISK IS WRITE PROTECTED appears on the CRT and the initialization is aborted If you still wish to initialize the disk remove ihe write protection and press INIT DISK INIT YES NO returns the inda menu without running the initialization will nof abort an initialization already in pro ogress PRIOR MENU returns the previous menu Operating Reference pu HP 87876 ONLY 7 ee PRA t a a aaa aaa Parana tra Maa de d 49 50 PRESET PRESET KEY SYSTEM SAVE Figure 26 PRESET Key INSTRUMENT STATE UR L7 mm S LOCAL e e e HP iB STATUS When the PRESET key is pressed or when the IP command is received from a system controller a self test is performed This is followed by presetting of the analyzer and the instruments
76. channel 1 trace data Define the maximum number of elements to be read into an array Define the actual number of elements read Read the trace data Perform error trapping Return the analyzer to swept mode The display now updates continuously Return from subroutine Define a subroutine that outputs commands to the analyzer Perform error trapping Return from the subroutine Running program 7 1 2 3 Clear the computer CRT and type in the program Press ALT R S on the computer The computer first presets the analyzer and source It then sets the source to 250 milliseconds per sweep and sets the analyzer to display transmission on channel 1 The computer commands the analyzer to take 10 sweeps and polis the analyzer status byte to determine when they were completed The computer reads a trace from the analyzer Just before the trace is sent you should see the display freeze as the TAKE SWEEP command is completed Press ENTER and the computer again tells the analyzer to take 10 sweeps This time the computer receives an interrupt after the last sweep The computer sits in a loop lines 330 and 340 and waits until the analyzer signals completion of the TAKE SWEEP command In this segment of the program you should not see the display freeze at all Immediately after it receives the interrupt the computer puts the analyzer back into swept mode This method of sensing the end of a TAKE SWEEP comm
77. character Line 460 Ifthe value returned is greater than zero then perform the foliowing operations Line 470 Remove keyword from the string and make it the current token Line 480 Increment the pointer along the data string Line490 Complete IF THEN sequence Line500 Return from the Get next token subprogram Line510 Define a subprogram called by Get next token subprogram Used to increment the pointer along the data string to the next word Line520 Return from the Get next token subprogram Line530 End of the Read citifile subprogram Running Program 12 1 Clearthe program memory of the computer and type in the program 2 Press RUN on the computer 3 The computer displays the prompt Name of filetoread At the prompt enter the name of the ASCII data file to be read by the program then press Continue The program will begin reading the file specified and display the data from the disk onto the CRT of the computer in a tabular format 4 The data will be listed as linear values for both the real and the imaginary components 21 oe 1 HP 8757C only Table 2 Alphabetical Listing of HP 8757C E Programming Codes 1 of 2 Averaging off A B ratio measurement A C ratio measurement Averaging on and factor d Adaptive Normalization on off A R ratio measurement Autoscale Autozero repeat on off of the DC detectors Autozero the DC det
78. connector or the device itself e If an SMA connector is to be mated to a precision 3 5mm connector the SMA connector must meet the setback specifications of precision 3 5mm connectors In particular there must be no protrusion of the plastic dielectric or of the shoulder of the male contact pin or the tip of the female contact fingers in front of the outer conductor mating plane The same gages can be used to measure SMA and precision 3 5mm connectors Separate male and female gages are required and connector gage kits containing all the items required are included in many Hewlett Packard calibration kits Gage kits are also available separately Part numbers are given in Part One of this Microwave Connector Care Manual Male SMA and Precision 3 5mm Connectors Gages used to measure male SMA and preci Sion 3 5mm connectors are usually marked M and have a circular metal bushing surrounding the gage plunger Figure 28 When the connector is gaged the outer bushing rests on the outer conductor mating plane and the male contact pin slips inside the gage plunger in this way the recession of the shoulder of the male contact pin is measured relative to the outer conductor mating piane Male gages are zeroed using the protruding end of the gage calibration block supplied with the gage This end of the gage block is usually also marked M Slip the calibration block into the outer bushing so that this bushing comes to rest on the outer flat area of
79. cursor markers and title Plots do not include status line information If a message is shown in the active entry area it will also be plotted If the message is not desired on the plot press ENT OFF in the ENTRY area before plotting PLOT CUSTOM causes the plotter to draw a plot using only the attributes specified with the DEFINE CUSTOM softkey in this menu Operating Reference HP 8757C E PLOT TRACES draws the data traces for all channels that are turned on Itincludes cursors cursor deltas and markers PLOT LABELS draws the mode labels reference line position labels frequency labels when turned on and status line information PLOT GRID draws the horizontal and vertical graticule lines DEFINE CUSTOM presents the custom plot menu and the message DEF INE CUSTOM PLOT appears on the CRT This menu lets you specify which plot attribute or combination of attributes will be included in a custom defined plot format The format you define is plotted when PLOT CUSTOM is pressed This is convenient for plotting repetitions of the same plot format The softkey labels for the attributes you select to plot are highlighted on the CRT TRACES presents the traces menu This menu lets you specify the trace or traces to be drawn on the plot Each of the trace softkeys such as TRACE 1 toggles on and off Only traces of channels that are turned on can be plotted PRIOR MENU returns the custom plot menu GRID inc
80. designed to be compatible with the HP 7440A 7550A and 7475A Plotters Other Hewlett Packard plotters notlisted here may also be compatible The analyzer expects to find the plotter at an HP IB address of 5 unless you have set a different address using the analyzer s LOCAL key Check the plotter to ensure that its address is correctly set When one of the plot softkeys is pressed the analyzer freezes the measurement data and then transfers this information to the plotter buffer Upon completion of the data transfer the analyzer is free to continue measurements while the data is plotting To speed up the process of plotting set PLT BUF ON OFF to OFF This function disables all analyzer functions except for plotting until completion of the plot If the plotter is incorrectly addressed or not connected to the 8757 SYSTEM INTERFACE the message PLOTTER NOT AVAIL appears on the CRT Once the problem has been corrected press the plot softkey again to begin plotting If the plotter is properly connected to the 8757 SYSTEM INTERFACE but has no paper loaded or is otherwise not ready to plot the message PLOTTER NOT READY appears on the CRT Once the problem has been corrected press the plot softkey again to begin plotting Limit lines and PASS FAIL indicators are included in the PLOT ALL and PLOT TRACES plots when turned on TURNER SINCE gn cease a ease E TRETEN PLOT ALL causes the plotter to draw the grid labels trace data
81. disk store and recall func tions of the HP 8757C Setting up the disk drive When utilizing an external disk drive the user must first set up the disk drive s HP IB address volume for a hard disk drive and unit number for a floppy disk drive Note that the HP 8757C can only access one drive at a time The fol lowing sequence demonstrates the setup procedure Setting the disk s HP IB address LOCAL Accesses the address menu DISK Displays the disk s current HP IB address in the active entry area of the display default address is 0 ENT Sets the new address to Setting the disk s unit and volume numbers SAVE Accesses the storage menu SET UP DISK Accesses the disk menu DISK UNIT Displays the current disk number in the active entry area usually 0 is the default value for the hard disk or the left hand drive on multiple disk units 1 ENT Sets the disk unit to DISK VOLUME Displays the current volume number floppy disk drives should have a volume number of 0 the default value 2 ENT Sets the volume number to 22 Initializing a blank disk The HP 8757C provides the ability to initialize either a 3 5 inch floppy disk or a hard disk from the front panel If the disk you wish to initialize is a 3 5 inch floppy insert the disk into the appropriate disk drive prior to beginning this procedure Note the following sequence will erase any information currently stored on the disk SA
82. following sequence demonstrates this feature Preset Connections Connect DUT as shown Controls Measurement CHANNEL 1 Activates channel 1 MEAS A R Sets up channel 1 for reflection measurement CHANNEL 2 Activates channel 2 MEAS B R Sets up channel 2 for transmission measurements Source parameters CF 10 24 GHz AF 2 GHz POWER LEVEL 10 dBm dB Calibrate Perform an open short calibration on channel 1 and a thru calibration on channel 2 Save Measurement Reconnect the DUT Adjust traces for the best data presentation with function keys i i H SS 5 ee eee 28 STAY 49 xESSOBUY 10 BASSE STOR 11 2408Hz Limit lines HP 8757C only Limit testing is a measurement technique that compares measurement data to user defined constraints Depending on the results of this comparison the HP 8757C will display either pass or fail above the grid Limit testing facilitates objective evaluation of your device s performance Deter mining whether a filter meets its passband and stopband specifications or an amplifier meets its minimum gain speci fication is easily achieved utilizing limit lines that provide quick convenient and repeatable results Limit testing also ensures that all devices are aligned and tested to the same specifications at each measurement station Limit testing is implemented by creating any combination of flat slop
83. hard drives with multiple partitions The valid range ford isO to 15 Deletes the last file selected from the disk or if no filename was selected the default file FILET is deleted if FILE1 existed on the disk Formats the disk in the disk unit last selected Loads from disk the items selected by x All information is recalled from the last file specified by the TIFs command If no filename was selected then the default file FILET is recalled from disk if FILE1 exists Valid selections for x are A Load all information files from disk M Memory trace only C CRT graphics only D Data traceonly I Instrument state only H Load all information files from disk hold display Stores to disk the items selected by x All information is stored into the last file selected by the TIFs command If no filename was selected then the default file FILE1 is overwritten Valid selections for x are A Store all information files to disk M Memory trace only C CRT graphics only D Data trace only I Instrument state only N Measurement Memory Defines the current active title foran existing ora new file Thestrings can beupto eight characters in length and include only letters or numbers For example Select a file named SAMPLE with TIFSAMPLE Before storing to loading from or deleting files from disk select a title 1 HP 8757C only 2 Revision 3 1 o
84. i I STAT 3 24n Oey CHSR amp 7564 8BMHz STOP 44 24608Hz The user should ensure that the DUT s output power is within the measurement range of the analyzer The analyzer can measure signals up to 20 dBm but is only specified to 16 dBm with the HP 11664 and HP 85025 series detectors On the low end the analyzer can measure signals down to 60 dBm with the HP 11664 series and to 55 dBm 50 dBm in DC mode with the HP 85025 series detectors When gt 80 dBm of dynamic range is required Application Note 327 1 describes how to utilize a HP 8349B Amplifier and an external leveling loop to extend the dynamic range of your measurement system 13 Averaging Averaging can reduce random noise measured by the HP 8757C E by applying weighted averaging to successive traces The averaging factor AVG FACTOR determines the number of sweeps over which the traces are averaged This function improves the accuracy and resolution of the calibra tion and measurement traces When averaging is on each successive sweep flattens the noise floor of the analyzer until the sweep count reaches the averaging factor value Users must be careful to adjust the device under test only after the averaging of the traces has settled and the value of the aver aging factor has been reached An A will be displayed in the center of the channel s mode label area when averaging is in use Averaging keystrokes Accesses averaging menu
85. in the AUX mode SLOPE LIMIT lets you define a sloped limit between two frequency points that is linear with frequency EDIT SEGMENT lets you redefine an existing limit line segment When you press this softkey the CRT prompts you for the number of the segment you wish to change Use the numeric keypad to enter the number of the segment to be changed then press ENT The entire segment will be deleted Re enter the segment First choose the limit type from the softkeys The CRT will then prompt you to enter frequencies and limit values DELETE SEGMENT lets you delete an entire segment Press the key and the CRT prompts youfor the segment number to be deleted Use the numeric keypad to enter the number of the segment to be deleted and terminate the entry with the ENT key POINT LIMIT lots you define a limit for a single frequency point DELETE ALL LNS lets you delete all existing limit lines for that channel MORE presents a second limits menu UPR LIM MEM places the upper limit line into memory and LWA LIM MEM E the lower limit line into memory Whenever either of the limit line to memory keys pressed the memory for the active channel is initialized with a 0 dB or 0 dBm C level The appropriate limits are then updated into memory in the order in which the segments were entered For overlapping limits the last entry will overwrite any overlap of ihe previous entry and points with no limit data will be e
86. into a connector Check the solvent periodically for contamination by pouring a few drops of the solvent onto a clean glass plate or microscope slide and letting it evaporate Then examine the glass in reflected light It should be perfectly clean and free of residue If it is not do not use solvent from that container Cleaning Technique In cleaning connectors apply a very smail amount of solvent to a cotton swab or a lint free cleaning cloth Then clean the connector as gently as you can Do not apply solvent directly to the connector for example from a spray can because this can lead to excessive cooling of the connector as the excess solvent evaporates Cleaning Connector Threads Clean the threads of the connectors first Every time a connec tion or a disconnection is made a small amount of metal wears off of the threads and this metal often finds its way onto the mating plane surfaces of the connectors Use a cotton swab and pure liquid Freon to scrub all connector threads Allow the solvent to evapo rate and then blow the threads dry with a gentle stream of clean low pressure compressed air Cleaning the Connector Mating Plane Surfaces When the connector threads have been cleaned apply a small amount of solvent to a new swab and clean the mating plane surfaces If the connector is a precision 7mm connector this should be done first with the center conductor collet removed Use very short horizontal or vertical strokes acros
87. is the last command in the statement Line90 Temporarily stop execution Line100 Setthe reference level to 10 dBm Again note the absence of a terminator Line 110 Temporarily stop execution Line 120 Set the reference position line to the center of the CRT 4th graticule No terminator is needed because this is the last command on the line Line 130 Temporarily stop execution Line 140 Program channel 2 to measure reflection input A instead of transmission input B Line 150 Temporarily stop execution Line 160 Many commands on one line with terminators Turn channel 2 off C2C0 and channel 1 on C1 Set the scale per division SD to 5 dB the refer ence position line RP to the center of the CRT and the reference level RL to 5 dBm Line 170 execution Running program 2 1 Type SCRATCH and press EXECUTE on the computer This erases the previous program 2 Type in this program and press RUN on the computer 3 The computer presets the analyzer and source and pauses Note the settings of channel 1 and 2 then press Continue 4 Channel 1 is turned off Channel 2 is now the active channel as you can see from the highlighted box around the channel 2 mode labels on the analyzer CRT Press Continue 5 Channel2 scale per division is now set to 10 dB It defaulted to 20 dB div at preset Press Continue 6 The reference level is set to 10 dBm it was 0 0 dBm
88. limit y units where x value is a frequency or value determined by the start stop labels x units is GZ for GHz MZ for MHz KZ for kHz HZ for Hz or blank for no units y units is DB for dB dbm SWR for SWR or V for volts Entering no value for an upper or lower limit value means do not test this limit An example LP 1 2 5 GZ 1 5 DB 1DB Limit is a flat line specified by s The string s includes the segment number 1 to 12 the start x axis value upper limit value lower limit value and stop x axis value in the following format LF seg no x start x units upper limit y units lower limit y units x stop x units where x value x units and y units are described above An example LF2 750 MZ 30 DB 32 DB 850 MZ Limit is sloped line specified by s The string s includes the segment number 1 to 12 the start x axis value start upper limit value start lower limit value the stop x axis value the stop upper limit value and the stop lower limit value in the following format LS seg no x start x units upper limit y units lowerlimit y units x stop x units upper limit y units flower limit y units where x value x units and y units are described above An example 154 2 GZ 3DB 4 DB 3 GZ 0 DB 1DB Limit line test on off Ifon limit test status is designated by the CRT PASS FAIL message and status bytes
89. menu only if an HP 85025C Detector Adapter is connected to the analyzer See the HP 85025C Detector Adapter Operating and Service Manual for instructions on this procedure This procedure is written to apply to the HP 87574 but is also compatible with the HP 8757C E PRIOR MENU returns the first calibration menu CONFIG SYSTEM forces the computation of the interna calibration tables for all detector inputs shown on the CRT See HP 8757C E Self Calibration in this section for more information MORE presents a second layer of the calibration menu DET OFFSET lets you set an offset value in dB for each detector You might use this to enter an offset that is the difference between the power reading of an analyzer input and the power reading of a power meter You might also use an offset to represent the value of attenuation used with a detector Pressing DET OFFSET presents another menu Select the detector for which you will set an offset value For example DET A The current offset value for that detector is shown inthe active entry area Change the offset value using the step keys knob or numeric keypad Terminate the entry with the dBm dB or ENT key The range of allowable entry values is 60 to 60 dBm However if the offset value procedure produces results outside the 20 to 70 dBm range for non ratio measurements or 90 to 90 dB for ratio measurements the analyzer will not be able to correctly show the dat
90. normalization 41 number of trace points 1 10 13 38 command IP QRG 11 TRACE POINTS softkey 38 numeric keypad 30 offset detector 24 101 softkey see TRACE POINTS open short calibration 22 UG8 operation local QRG 6 IPG 3 IPV 4 remote QRG 6 IPG 3 IPV 3 operator s check 63 options fourth detector input 1 5 HP IB disk drive 1 5 extended service 1 6 factory refurbished demonstration instrument 1 6 rack mount without handles 1 6 rack mount with handles 1 6 output data functions QRG 5 output modes commands QRG 16 17 cursor value QRG 16 CW value QRG 16 error status QRG 17 identlly udo ceram ae Bala ae QRG 17 interrogated parameter value QRG 16 keycode QRG 17 knob value QRG 17 learn String e eek ee QRG 16 measurement data QRG 16 memory data QRG 16 normalized data QRG 16 status bytes QRG 17 OUTPUT VALUE IPG 8 IPV 10 packaging 2 14 PASS FAIL indicators 6 28 passthrough Address 2 QRG 4 address command QRG 14 CRT graphics QRG 5 MOUS 4 Gi ce cw IPG 6 IPV 6 performance
91. of precision 3 5mm connectors In particular there must be no pro trusion of the plastic dielectric or of the shoulder of the male con tact pin or the tip of the female contact fingers in front of the outer conductor mating plane e Take great care with alignment Dimensions of SMA and precision 3 5mm connectors differ enough that the male SMA pin can slip to the side of the female contact fingers in the precision connector Align the connectors carefully and avoid twisting the connectors or devices as the connection is made e Whenever possible use 3 5mm to 3 5mm adapters as connec tor savers between the SMA connector and the precision 3 5mm connector Using an adapter has only a small effect on electrical performance and wear or damage occurs only on the adapter not on expensive components or devices One key feature of precision 3 5mm connectors is that they can be mated with SMA connectors Figure 23 This was among the original design objectives for the connector But great care is neces sary when making such connections to avoid damaging the connectors owing to their slightly differ ent dimensions and mechanical characteristics The recommendations above will help prevent damage when SMA connectors are mated to precision 3 5mm connectors Gage both connectors carefully be sure that the setback specifications for preci sion 3 5mm connectors are also met by the SMA connector and take great care with alignment Push
92. of the current measurement You can easily program other start and stop frequencies by following the example in program 3 On the computer CRT print the value and actual frequency of the cursor End program execution Define a subroutine that outputs commands to the analyzer Perform error trapping Return from the subroutine Line 360 Line 370 Line 380 Define a subroutine that outputs commands to the source through the passthru address of the analyzer Perform error trapping Return from the subroutine Running program 4 1 2 3 Clear the computer CRT and type in the program Press ALT R S on the computer The computer turns on both channels and sets channel 1 to reflection input and channel 2 to transmission input B The cursor is positioned to the maximum point on the channel 2 trace and its value and position are read and displayed At preset the number of points per trace is 401 The computer displays the prompt Desired cursor position 0 4002 Type in a number between 0 and 400 and press ENTER A position of 0 represents the left side of the analyzer s CRT lowest frequency and 400 represents the right side of the CRT highest frequency The position is set and the cursor s value and position is read and printed on the CRT of the computer The computer stops and displays the prompt Cursor frequency GHz Enter a frequency within the current start and stop freq
93. of the center pin not in the mating plane offsets Several mechanical specifications for Type N connectors exist among them those listed in Table 4 All specify a minimum recession of the shoulder of the male contact pin and a maximum protrusion of the tip of the female contact fingers The strictest specification is the HP Precision specification which differs from MIL C 39012 Class ll in reducing by 0 001 in the minimum allowable recession of the shoulder of the male contact pin None of the specifications allows the total contact separation to be zero or less and most require a minimum contact separation of 0 001 in or more Only the HP Precision specification allows a sepa ration of zero Before gaging any Type N connector therefore consult the mechanical specifications provided with the connector or the device itself Table 3 Mechanical Specifications Type N Connectors Specification Recession Male Protrusion Female MIL C 71B 0 214 0 232 in 0 187 0 207 in CONTACT SEPARATION 0 007 0 045 in 39012 Class I 0 208 in minimum 0 207 in maximum CONTACT SEPARATION 0 001 in minimum MIL C 39012 Class 0 208 0 211 in 0 204 0 207 in CONTACT SEPARATION 0 001 0 007 in HP Precision 0 207 0 210 in 0 204 0 207 in CONTACT SEPARATION 0 000 0 006 in Type N Connectors TYPE N CONNECTORS RECESSION OF MALE CONTACT PIN SHOULDER FEMALE RECESSION OF FEMALE CONTAC
94. of the current information by selecting one of the other options SELECT CHAR DONE STORE TO DISK ALL RECALL FILE DIRECT Accesses the recall menu Displays a directory of files stored on the disk Selects the file title at the cursor use the front panel knob to move the cursor up and down the file directory Initiates the external recall function Retrieves all of the file information the user may choose to retrieve onlv a portion of the file by selecting another option SELECT FILE LOAD FR DISK ALL 23 Special functions Color selection HP 8757C only One of the notable characteristics of the color selection func tion is the flexibility afforded the user to match his or her personal preferences Each of the displayed notations such as the channel information warnings and labels as well as the grid and background may be adjusted individually For those desiring a monochrome display that is also available by the selection of a softkey Color selection is a global function it is not affected by pre set or recalling a measurement from an internal storage register When a file is retrieved from an external disk the color selections stored in that file will be retrieved The display colors have been optimized to present the most pleasing and effective display If the color selection must be changed the HP 8757C allows quick modification via a color list menu The color list prov
95. only where function and is explained under the command description Example WK1TEST1 WT PASSBAND INSERTION LOSS If INSERTION LOSS WT PASSBAND INSERTION LOSS Valid characters Commands associated with the C detector are valid only for the HP 8757C Option 001 which has the fourth detector C input If a command associated with the C detector is sent toa standard HP 8757C not Option 001 or an HP 8757E it will be treated as an unknown command Instrument preset A self test is first performed when the PRESET key is pressed or when the IP command is received by the analyzer This is followed by presetting the analyzer and the instruments con nected to the 8757 SYSTEM INTERFACE All functions are turned off then the following is set HP 8757C E Channels 1 and 2 on The channel menu appears in the soft key label area of the CRT Measure power A on channel 1 Measure power B on channel 2 Measure power C or B on channel 3 Measure power R on channel 4 Display measurement data in log magnitude format Scale 20 dB div Reference level 0 dB for all channels m Reference level step size 20 dB m Averaging off Averaging factor 8 m Cursor off All labels on Channel 1 as the active channel m Modulation drive on m Numberof points 401 m Detector mode set for AC detection m Smoothing set for 5 096 of span off W Cursor format log magnitude Search value 3 dB
96. panel failure Table 1 is the list of error codes and most probable cause of failure If you encounter an error message refer to the service manual for trou bleshooting Table 1 Summary of Error Codes LED Error i Probable Cause Pbi Test Description Explanation of Failure Microprocessor kernel A3 ROM checksum RAM checksum A3 Power supply A12 instrument bus A3 A6 Display interface GSP 14 Display interface DRAM bus 14 Dispiay interface DRAM download A14 Display interface DRAM celi A14 Display interface VRAM bus 14 Display interface VRAM cell A14 Display interface Video control A14 Display interface RGB A14 Interrupt test A3 A14 A2 A4 A6 Other self test failure includes As indicated on CRT EEROM Write Enable Battery failure Unexpected Keypress Configuration Error Pretest pass we h awk b d O Cc 7AM obama 8 7 6 5 4 3 2 1 In Case of Difficulty HP 8757C E SYSTEM OPERATION If the analyzer is configured as the system controller with other instruments connected to the 8757 system interface bus problems may occur in the configuration itself rather than in a specific instru ment General Press PRESET on each instrument or cycle the power In normal operation avoid pressing PRESET on the source this may cause a system lock up Isolate each instrument by disconnecting and reconnecting them one at a time from the analyzer system interfac
97. port connections to connect ordinary 7mm devices to ordinary 3 5mm devices Figure 27 85130A Special 3 5mm F to Precision 7mm Adapters SMA and Precision 3 5mm Connectors 65 66 CLEANING SMA AND PRECISION 3 5mm CONNECTORS e Use great care to avoid bending or breaking the center conductor pins Female contact fingers in precision 3 5mm connectors are especially easy to damage Avoid wetting plastic support parts Use the least amount of solvent possible and blow connectors dry with a gentle stream of compressed air SMA and precision 3 5mm connectors require special care in cleaning because of their delicacy smail size and intricate geometry Center conductor contact pins especially the contact fingers on female connectors are very easily bent or broken in precision 3 5mm connectors moreover the center conductor is supported only at the inner end by a plastic dielectric support bead This makes it very easy to bend or break the center conductor Magnification and good lighting are helpful and especially for cleaning the interior surfaces of these connectors the method given in Part One of this Microwave Connector Care Manual is recom mended cutting off the sharp tip of a round wooden toothpick wrapping it with a single layer of lint free cleaning cloth and moistening the cloth with liquid Freon Insert the cloth carefully into the connector to clean the interior surfaces When it has been cleaned blow th
98. pressed before continuing Turn channel 1 off and channel 2 on Command the analyzer to display the trace memory from channel 2 Initialize the variable specifying the number of elements actually read into the array Set the data format to PC binary format Command the analyzer to output its channel 2 measurement trace data Read the binary measurement data from channel 2 Perform error trapping Disable the end of line string carriage return linefeed that is sent after any IOOUTPUT command Command the analyzer to input data into the trace memory of channel 2 Line 340 Line350 Line 360 Line 370 Line 380 Line 390 Line 400 Line 410 Line 420 Line 430 Line 440 Line450 Line 460 Line 470 Line 480 Line 490 Line 500 Enable the end of line string carriage return linefeed that is sent after any IOOUTPUT command Write the binary data array back to the trace memory of channel 2 Perform error trapping Press ENTER to continue Print a message on the computer s CRT notifying the user that the computer is waiting for a key to be pressed before continuing Set up a loop to create 401 measurement points Calculate some arbitrary function and fill the binary data array This function has no particular meaning but represents some special calibration data such as an open short average End of the loop Turn channel 2 off and display the channel 1 trace memory Disable
99. pressed on its front panel In some applications it is useful to put the analyzer into local operation so that it can be controlled from the front panel and still generate interrupts whenever a key is pressed 17 Program 9 CRT graphics For applications requiring diagrams drawings or special limit lines the CRT of the analyzer may be used as a plotter This program draws a connection diagram for a hypothetical test system measuring an amplifier It will blank the ana lyzer s standard display containing the graticule annotation and softkeys so that we have a blank Figure 2 shows what the CRT should look like when the program is done For fast easy to use graphics the graphics memory of the HP 8757C E is divided into seven pages of 500 words One vector requires two words Each of the pages may be selected to receive data and turned on and off indepen dently You can keep different drawings in each of the graphics memory pages and simply turn on the drawing you need by turning on the appropriate page Each page may also be erased independently To use the graphics capability of the HP 8757C E first define the passthru address to be one less than the analyzer s control address If the analyzer s address is 16 its graphics address is 15 To the computer the CRT of the analyzer looks like a plotter connected to the 8757 SYSTEM INTERFACE Program 9 listing 10 REM INCLUDE QB4SETUP 20 CLS 30 15 amp 7
100. program can be used to read the data files and display the contents of those files on the computer s CRT display No frequency information is read or displayed The CITIFile Common Instrumentation Transfer and Interchange File disk format is used on the data disks for the HP 8757C This program reads in a single array of data from a CITIFile data disk It then outputs the point number and the magnitude associated with that point In order to use this program you must have saved either memory or measurement data in files onto a disk with the HP 8757C In addition this data needs to be stored in ASCH format in order for it to be read by the CITIFile routine 19 Program 12 listing 10 INTEGER Intvar 1 30 Counter 20 REAL Data_pt 1 1601 1 2 1 1 30 DIM Filename 30 40 LINPUT Name of file to read Filename 50 Read citifile Filename Data pt Intvar 60 PRINT POINT REAL IMAG 70 FOR Counter 1 TO Intvar 1 80 PRINT Counter TAB 10 Data pt Counter 1 1 TAB 24 Data pt Counter 2 1 90 NEXT Counter 100 PRINT Printed the data array from file Filename 110 PRINT The file contained an array with Intvar 1 data points 120 END 130 SUB Read citifile Filename Data pt INTEGER Intvar 140 INTEGER Done Count1 150 ALLOCATE Current line 256 Token found 32 160 ASSIGN Disk TO Filename 170 Done 0 180 REPEAT 190 ENTER Disk Current_line 200 Current line TRIM C
101. reasons Hewlett Packard recommends that before deciding that a connector is out of specification at least four things be done Clean the connector the connector gage and the gage block again following carefully the suggestions on cleaning made earlier in this Microwave Connector Care Manual Zero the gage again and repeat the measurement Measurements in which differences of 0 0001 inch are significant can be affected greatly by dirt and contamination Measure the connector several times yourself and also have another person make some measurements in order to determine an average reading This technique will help reduce uncertainties due to differences of technique and random variations in gage accuracy Measure the connector using several different orientations of the gage within the connector Averaging several readings each taken after a quarter turn rotation of the gage will reduce measurement variations that result from the gage or the connector face not being exactly perpendicular to the center axis Avoid holding the connector gage any other way than by the gage barrel below the dial indicator Holding the gage by the barrel offers maximum stability It also improves measurement accuracy by preventing stresses from being applied to the gage plunger mechanism through the dial indicator housing as occurs when the gage is cradied in the hand or held by the dial indicator In addition keep records of the setback measurem
102. seconds to allow the trace to settle Press CURSOR MAX to find the trace maximum The CRSR value displayed in the active entry area now represents the minimum insertion loss of the microwave test device This value will be plotted with the data trace puc Press SYSTEM PLOT PLOT ALL to generate a hard copy plot Keep this plot for comparison with future operator s checks Disconnect the detector from the A input and connect it to the B input Remove the microwave test device from the circuit and connect the input of the detector to the RF output of the source Press DISPLAY MEAS MEAS B AVG AVG OFF Repeat steps 6 through 12 Repeat step 13 for the remaining detector inputs pressing MEAS the softkey corresponding to the detector input connected Operating Reference HP 8757C E LNT R Q D UU XC T 1 USERS GUIDE This document is intended to provide an introduction to the operation of the HP 8757C E scalar network analyzer It is organized in a manner that will familiarize the user with many of the capabilities and features of the HP 8757C E illustrating actual operating sequences for various measurements Chapter 1 provides a basic introduction to the HP 8757C E s front panel then leads the user through the general measure ment procedure for making scalar network measurements Chapters 2 and 3 describe the procedure for making transmis sion and reflection measurements The examples have been s
103. softkey 25 CHAN 3 softkey 9 CHAN 4 softkey PV 9 CHAN 1 COLOR softkey 15 ICHAN 2 COLOR softkey 15 CHAN 3 COLOR softkey 15 CHAN 4 COLOR softkey 15 CHAN 1 OFF softkey 9 CHAN 2 OFF softkey 9 CHAN 3 OFF softkey 9 CHAN 4 OFF softkey 9 CHANNEL Keys 8 CHANNEL 1 key 9 CHANNEL 2 key 9 channe activo eso vee as 9 und tesis bt ut 25 14 UG 24 mons eure bee VIDES 9 selection commands QRG 8 HP 8757C E Operating Manual CH MENU ON OFF softkey 40 clear programming message QRG6 FEGISIONS wales eek ELA 40 CLEAR SAV RCL softkey 40 COARSE ZERO softkey 24 COLOR softkey 16 color adjusting 14 UG 24 bfidhinass iced x ERE DES 16 deficient vision 15 ect usua fe aep te 15 tint oto cues s Phe Pee 16 COLOR BRTNESS softkey 16 CONFIG SYSTEM softkey 24 configuration problems DIF 3 see aiso interconnections configure system UG7 UG 11 see also interconnections commands QRG 22 23 IPG 22 IPV 24 connector ADGAN 1 11 62 care see Connector Care Manual CONTROL T n bes wc es oh da 62 CONTROL 2 62
104. source digital plotter printer and disk drive HP 8757C only are connected to the 8757 SYSTEM INTERFACE This connection allows the analyzer to control and extract information from the other parts of the measurement system To allow you to control other instruments with the computer the analyzer has a built in PASSTHRU command that takes a command from the computer and passes it on to one of the instruments connected to the 8757 SYSTEM INTERFACE To initiate passthru mode tell the analyzer which instrument you wish to command by setting the passthru address Talk or listen to that device address the analyzer s special passthru HP IB address which is different from the analyzer s HP IB address While in the passthru mode the analyzer stops updating its CRT and does not respond toits front panel because it s in remote mode remove the analyzer from passthru mode address it via HP IB While in passthru mode do not press LOCAL on the analyzer The analyzer s passthru address is calculated from its HP IB address If the address of the analyzer is even such as 16 decimal then the passthru address is the next larger number 17 decimal If the address of the analyzer is odd such as 15 decimal then the passthru address is the next smaller number 14 decimal Never set the address of the analyzer so that its address conflicts with one of the instruments connected to the 8757 SYSTEM INTERFACE For instance if the
105. source is set to 19 decimal do not set the analyzer address to 19 Data can be sent to or received from any instrument on the 8757 SYSTEM INTERFACE via passthru mode The IOLOCAL IOREMOTE and IOTRIGGER HP IB messages do not pass through the analyzer Program 3 listing 10 REM INCLUDE GBSETUP 20 CLS 30 ISC amp 7 40 Snag 716 50 Passthru 717 60 CALL IOTIMEQUT ISC amp 10 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 70 CALL IGABORTCISCE amp 3 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 80 CALL IOCLEARCISC amp O IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 A IP GOSUB IQQUTS A PT19 GOSUB IODUTS A GOSUB IODUTSP CALL IGENTERCPassthru amp Min freq IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Min freq Min freq 1 09 A GOSUB IOQUTSP CALL IOENTERCPassthru amp Max freq IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Max freq Max freq 1 09 A GOSUB IOQUTS PRINT Frequency limits Min freq Max freq GHz INPUT Start frequency GHz Start fregq INPUT Stop frequency GHz Stop freq A FA STRECStart freq GZ FB STRSCStop freq GZ GOSUB IODUTSP A H GOSUB IODUTS END TOOUTS CALL IQOUTPUTS Sna A LENCAS gt IF PCIB ERR NOERR THEN ERROR PCIB BASERR RET
106. surfaces again When the connector is attached to a small component or to a cable or calibration of verification standard the easiest way to do this is to put a lint free cleaning cloth flat on a table and to put a drop or two of cleaning solvent in the center of the cloth Figure 5 Note that it is not necessary to remove the collet in order to use this cleaning method Retract the connector sleeve threads so that the connector interface is exposed Then gently press the contact end of the connector into the cloth moistened with solvent and turn it Dirt on the connector interface will be scrubbed away by the cloth without damaging the connector Blow the connector dry with a gentle stream of compressed air Keep the cioth in a plastic bag or box so that it does not collect dust or get dirty when not in use This cleaning method can be adapted even for fixed connectors such as those attached to test ports Simply fold the cioth into several layers of thickness moisten it press it against the connector inter face and turn it to clean the connector Blow the connector dry with a gentle stream of compressed air Drying Connectors When you have cleaned a connector always be sure that it is completely dry before reassembling or using it Blow the connector dry with a gentle stream of clean compressed air and inspect it again under a magnifying glass to be sure that no particles or solvent residues remain Cleaning CLEANING INTERIOR SURFACES
107. the points you need Program 4 listing 10 REM INCLUDE QBSETUP 20 CLS 30 Start freq 2 40 Stop freq 5 50 15C amp 7 60 Snag 716 70 Passthru amp 317 CALL IOTIMEQUTCISC amp 10 2 IF PCIB ERR NOERR THEN ERROR PCIB BASERR CALL IOABORTCISC amp IF PCIB ERR NOERR THEN ERROR PCIB BASERR CALL IOCLEARCISC amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A IP GOSUB IO0UTS A PT19 GOSUB IODUTS A FA STRS CStart freq GZ FB STR CStop freq GZ GOSUB IOQUTSP A C2 CXDC GOSUB IOQUTS Max 2 Actual 0 DIM Cursor vals Max CALL IQENTERACSna amp SEG Cursor vals 0 Max ActualZ IF PCIB ERR NOERR THEN ERROR PCIB BASERR PRINT Cursor reads Cursor valst 02 dB at position Cursor vais 1 INPUT Desired cursor position 0 400 New posn A SC STRSCINTCNew posn 522 050 100075 A DC GOSUB 100075 100 110 130 140 150 160 170 180 130 200 210 220 230 240 250 260 270 280 290 300 310 320 330 340 350 360 370 380 CALL IGENTERACSna amp SEG Cursor vals 0 Max ActualZ IF PCIB ERR NOERR THEN ERROR PCIB BASERR PRINT Value at position Cursor vals 1 5 ds Ws Cursor valsC0D dB INPUT Cursor frequency GH2 Cur freq New posn 400 Cur freq Start freq Stop freq Start freq A SC STRSCINTCNew posn 522 GOSUB IOBUTS AS OC GOSUB IODUTS CALL IOENTERACSna amp SE
108. the final connection using the recommended torque wrench Some wear of the gold plating on the mating plane surfaces due to abrasion does occur when this technique is used and for this reason seating is generally omitted except in the most demanding measurement applications in order to extend the life of the connectors This latter consideration may be primary in high volume and production environments in most lower frequency applications and when the utmost in repeatability is not required Above all even when seating is not used it is essential that the connectors be clean and undamaged Connector wear is greatly accelerated if the connectors have not first been inspected visuaily cleaned and gaged correctly or if the connection is very tight when the connectors are rotated The seating technique described here must never be used as a substitute for careful cleaning and complete mechanical inspection of connectors Inspect and clean connectors care fully Do not overtighten the preliminary connection Precision 7mm Connectors Seating Precision 7mm Connectors HOLD CONNECTOR NUT STATIONARY TURN BODY OF THE DEVICE 5 TO 15 DEGREES OPPOSITE DIRECTION OF TIGHTENING Make the preliminary connection lightly 2 inch ounces Do not turn devices more than 15 degrees Use a torque wrench to make the final connection Figure 16 Seating Precision 7mm Connectors Precision 7mm Connectors 41 42 ADAPTERS FOR PRECISION 7mm CON
109. the internal plotter buffer of the analyzer e New softkey ALL HOLD has been added to the RECALL key menu The corresponding remote command is LFH This function loads the files listed in the ALL function in addition to holding the measurement display New softkey MEAS MEM has been added to the SAVE key menu The corresponding remote command is SFN This function stores normalized trace data to disk that can later be analyzed with a computer New softkey STEP SW ON OFF has been added to the SYSTEM key menu The corresponding remote command is FSm This function enables the step sweep mode when using an HP 8340 or HP 8360 and connected to the 8757 SYSTEM INTERFACE New system interface compatibility with HP 8360s including master slave source configurations 3 2 HP 8757C E Operation CONTENTS 1 What ls in this Reference 2 How to Use this Reference 4 Front Panel Features 5 CRT Description 8 Front Panel Operation 8 CHANNEL Keys 9 CHANNEL fi 9 CHANNEL 2 10 FUNCTION Keys 11 MEAS 12 DISPLAY 17 SCALE 18 REF 19 CURSOR 21 AVG 22 CAL 25 HP 8757C E Self Calibration 27 SPCL 30 ENTRY Area 31 INSTRUMENT STATE Keys 32 SYSTEM 34 Plotting 36 Printing 38 Other SYSTEM functions 38 Secure Frequency Mode 42 LOCAL 43 SAVE 47 RECALL 50 PRESET 52 HP IB STATUS 53 Detector Inputs 54 HP 8757C Softkey Menu Structure Map 58 HP 8757E Softkey Menu Structure Map
110. the protruding end of the block into the circular sleeve so it comes to rest on the gage plunger inside the female bushing Zero the gage according to the instructions given in Part One of this manual Then measure the connector insert the gage carefully into the female connector so that itis centered and the female contact fingers in the connector slip inside the protruding circular sleeve on the gage The circular sleeve on the bushing should come to rest on the outer conductor mating plane inside the connector behind the female contact fingers Gently rock the connector gage within the connector to make sure that the gage and the outer conductor have come together flatly When the gage pointer settles consistently at a reading read the gage indicator dial Counterclockwise deflection of the gage pointer a minus reading on the gage indicator dial indi cates that the tip of the female contact fingers meets the specification of protruding no more than 0 207 inches The amount of deflection tells how much less than this maximum the tip of the female contact fingers is protruding A reading of minus 0 003 inches for example indicates a protrusion of 0 204 inches the minimum protrusion allowed in HP Precision Type N connectors in the same way clockwise deflection of the gage pointer a plus reading on the gage indicator dial indicates that the tip of the female contact fingers is protruding more than the maximum of 0 207 i
111. to change the brightness intensity of the display When pressed BRTNESS DISPLAY appears in the active entry area of the CRT along with the value last entered 100 is the specified brightness level 100 is equivalent to 100 nits units of luminance at shipment Use the front panel knob or numeric keypad to enter a new value Terminate the entry with the ENT key You can adjust the brightness value down or up although the display quality is not specified above 100 The maximum value depends upon the individual display The brightness level is not changed at preset unless the level has been set below a defined minimum This minimum brightness level can be changed Instructions are in the service manual HP 87576 ONLY 7 9 M The brightness adjustment softkey is accessed by first pressing ADJUST DISPLAY Adjusting Color explains all of the ADJUST DISPLAY softkeys MEAS gt MEM stores the current measurement data into memory The data is stored in dB dBm format even when you are viewing the data in SWR format Voltage data ADC IN can also be stored into memory MEAS M MEM stores the measurement minus memory normalized trace into memory This func tion can be used for ratio measurements only Horizontal Display Data Resolution The horizontal display resolution of the analyzer depends on the number of points seiected and the number of measurement traces as shown in table 2 To change the number of t
112. to test ports by folding the cloth and pressing it onto the connector Precision 7mm Connectors PRECISION 7mm CONNECTOR DIELECTRIC OUTER CONNECTOR SLEEVE SUPPORT BEAD CONDUCTOR NUT FULLY EXTENDED CENTER CONDUCTOR COLLET MATING PLANE PROTRUSION OUTER CONDUCTOR COLLET CENTER CONDUCTOR COLLET IN PLACE Measure collet protrusion If attached remove aligning pin from connector gage Use flat end of gage calibration block CENTER CONDUCTOR COLLET REMOVED Measure center conductor recession Center conductor must not protrude beyond outer conductor mating plane Airlines require attaching the aligning pin to the connector gage in these cases use the recessed end of the gage calibration block Figure 13 Precision 7mm Connector Precision 7mm Connectors 33 34 Removing Center Conductor Collets Figure 14 shows how to remove the center conductor collet from a precision 7mm connector This is required in order to gage the connector with the collet removed if the collet is damaged or if the protrusion of the collet is not within specification Pull back the handle of the collet removing tool Figure 14 to open the interior collet removal jaws fully Keep the handle pulled back and the jaws open and insert the too carefully but completely into the connector inside the outer conductor until it comes to rest lightly on the interior support bead Release the handle and remove the tool and co
113. used to measure a fourth parameter for example where a device under test has more than one output Input R is typically used for the reference detector input for ratio measurements 1 HP 8757C Option 001 only 8757C E Operating Beference 53 SOFTKEY MENU STRUCTURE MAPS DISPLAY COLOR Figure 29 The HP 8757C Softkey Menu Structure Map 1 of 4 54 Operating Reference 8757 CURSOR SHORT 8787C OPT 001 ONLY SEE HP85025C OPERATING AND SERVICE MANUAL Figure 29 The HP 8757C Softkey Menu Structure Map 2 of 4 HP 8757C E Operating Reference 55 SYSTEM 1 See Section 8 To Channel Service Manual Menu Figure 29 The HP 8757C Softkey Menu Structure Map 3 of 4 56 Operating Reference HP 8757C E RECALL Figure 29 HP 8757C Softkey Menu Structure Map 4 of 4 HP 8757C E Operating Reference 57 MEAS DISPLAY SCALE Figure 30 HP 8757E Softkey Menu Structure Map 1 of 3 58 Operating Reference HP 8757C E SEE HP85025C OPERATING AND SERVICE MANUAL Figure 30 The HP 8757E Softkey Menu Structure Map 2 of 3 HP 8757C E Operating Reference 59 60 Operating Reference See Section 8 To Channel Service Manual Menu Figure 30 The HP 8757E Softkey Menu Structure Map 3 of 3 HP 8757C E REAR PANEL FEATURES Figure 31 The HP 8757C Rear Panel The 8757 SYSTEM INTERFACE connec
114. which iets you ioad the instrument state trace data and CRT graphics from disk The active file title in the title area on the CRT identifies the file to be loaded H you want to load information from a different file enter the desired file title using the TITLE FILE softkey or select the file title in the file directory If no file exists on disk with the current active file title the message WARNING NOFILE FOUND ON DISK appears on the CRT Return to the previous menu and use the fiie directory to verify that you have the correct file title and the correct E NOTE Alternate state information cannot be saved on disk therefore it cannot be recalled HP 8757C E Operating Reference 47 48 MM M HD TTC ONLY 9 When pressed LOAD FR DISK presents another menu INSTRM STATE loads instrument front panel settings from disk This information must have been previously stored under the current active file title MEAS MEM IIoadstrace measurement data from disk into the analyzer trace memory This information must have been previously stored under the current active file title MEM loads trace memory data from disk This information must have been previousiy stored under the current active file title stored under the current active file title ALL loads the instrument state trace measurement and memory and CRT graphics from disk in one o
115. within 10 to 40 dBm the specification for the HP 8757C E with the HP 11664A E is 0 1 dB 0 01 dB dB 1 HP 8757C only 1 8 HP 8757C E General Information Table 1 1 Specifications and General Requirements 2 of 2 Absolute Power Accuracy 50 MHz 25 5 C DC mode P 85025A B 10 20 Power dBm 16 dm GENERAL REQUIREMENTS General requirements identify specifications required of the source in order for the analyzer to operate properly Sweep Time Minimum sweep time and maximum number of displayed traces on the CRT depend on the horizontal resolution number of points Number of Minimum Sweep Time ms 60 70 90 100 150 200 NA NA NA NA Modulation Requirements for use with HP 11664 Detectors HP 85025 26 Detectors and HP 85020 27 Bridges in AC mode Square wave amplitude modulation Frequency 27 778 20 Hz z 30 dB on off ratio 45 to 55 symmetry Sweep Voltage Requirements Sweep In Horizontal sweep voltage from 0 to 10 volts provided by the source through the SWEEP IN 0 10V input on the rear panel of the analyzer Other sweep voltages can also be accepted by using the non standard sweep mode of the analyzer Marker and Blanking Requirements Pos Z Blank Blanking and marker signals are provided by the source through the POS Z BLANK input on the rear panel of the analyzer Voltage levels Blanked SV typical Unblanked OV typical Marker 4V typical Active Marker
116. 00 NEXTI 220 OUTPUT gGSna C2C0 CIMY 230 OUTPUT Sna USING K FD1 WM 240 OUTPUT Fast_sna Bin_dat 250 OUTPUT gGSna AS 260 END Program 6 explanation Line10 Assign an I O path to the address of the analyzer Line 20 Assign another I O path to the address of the analyzer to be used for fast binary transfers Line 30 Abort any transfers and clear the HP IB interface of the computer Line40 Clear the HP IB interface of the analyzer Line50 Preset the analyzer and the source This sets the number of points per trace to 401 Line60 Dimension an array to hold a trace in ASCII format An array is 401 elements 0 to 400 inclusive Line70 Dimension an array to hold a trace in binary format It is also 401 elements Line80 Set channel 1 to reflecion input A and channel 2 to transmission input B Line90 for the source to sweep a few times to insure the traces contain valid data When you command the analyzer to output a trace it responds immediately Line100 Set the format to ASCII and command the ana lyzer to output the channel 1 measurement trace data Line 110 Read the measurement trace Note the use of an asterisk to designate the entire array Line120 Write the measured trace back to the trace mem ory of channel 1 Reading the measurement trace and storing it into the memory trace is equivalent to executing the MEAS MEM function SM Line130 Temporarily stop program execution Line
117. 1 21 AVG FACTOR softkey 21 AVG ON OFF softkey average 21 calibration 23 INDEX B B softkey 11 BJA softkey 11 B C softkey 11 BIR softkey 11 BACKGROUND softkey 15 background color see color adjusting BACKSPACE softkey recall zou demie ERE 49 SAVE oki ka tag othe S afe eerie aces 45 SYSIOM uod bep E Rd 39 bandwidth 3 dB see cursor BINARY FORMAT softkey tacall ele RD Ee au uu 49 ILU Qe be rr 46 BLACK softkey 15 bianking frequency readout see secure frequency mode labels osi ed warp ek E aks 38 BLUE softkey 15 brightness SOI Soeur n Caes ic dy n 16 displaV ios ee REED oe 13 BRTNESS softkey 13 G softkoy 2 case ence 11 C A softkey 1 C B softkey 1 C R softkey 11 cables HP IB 1 8 CAL key 22 Calibratlon UG 8 25 detector power 25 external detector 25 internal tables 25 problems DIF 4 self calibration 25 short open 22 UG 8 IU esses mer aoe EA 23 UG 8 CAL VALUE
118. 1 Actual 0 CALL IOENTERACSna amp SEO ASCIIDATCO MaxZ Actual IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR AS S1 GOSUB IOQUTS DO UNTIL INKEY CHR C132 LOCATE 25 PRINT Press ENTER to continue LOOP PEN OFF A SWO CS RMIG CALL IUPENCIsc amp 09 ON PEN GOSUB Srq recv PEN ON A TS10 15 Wait srq IF Intr bit PEN OFF END Srq recv CALL IU0SPOLL Sna amp Intr bitu lt gt NDERR THEN ERROR PCIB BASERR AS GOSUB IQQUTS C10D GOSUB IOQUTS Maxx 401 ActualZ 0 CALL IOENTERACSna amp SEG ASCIIDATCO Maxz Actual IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR AS Sy1 RETURN IGQUTS CALL IOGUTPUTS CSna amp A LENCA 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR RETURN gt H od GOSUB IGQOUTS GOSUB IODUTS GOSUB 100075 0 THEN GOTO Wait srq IF PCIB ERR GOSUB 000 5 Program 7 explanation Linel0 the QuickBASIC initialization file OBSETUP Line20 Clear the computer CRT Line30 Dimension an array large enough to hold a trace of data 401 points Line 40 Assign the interface select code to a variable Line50 Assign the address of the analyzer to a variable Line60 Assign the passthru address of the analyzer to a variable Line70 Define a system timeout of 10 seconds Perform error trapping Line80 Abort any HP IB transfers Perform error trapping Line90 Clear the HP IB interface of the analyzer Perform e
119. 1 8 1 9 accessories 1 6 active entry area 6 ADPT NM ON OFF softkey 40 adaptive normalization 6 40 UG 15 command QRG 11 ADC IN connector 1 11 62 see also AUX address assignment eA Y QRG 7 HPIB cits be 2 13 42 passthrough QRG 4 ADJUST DISPLAY softkey 15 ALL softkey recall irra ose Rae 48 Save 44 ALL HOLD softkey 48 alternate sweep DIF 5 UG 21 altitude requirements see environment analyzer ACCESSOS rakes seve See s 1 6 description 1 4 OPUONS ovii s eei ea 1 5 specifications 1 3 1 8 aperture smoothing 27 ASCII modified character set QRG 20 see aiso transfer speed ASCII FORMAT softkey recall ule nee 49 Rav 46 attributes of CRT 15 autocalibration 25 AUTOCAL ON OFF softkey 25 autoscale oranie ves ao Osa ees 17 AUTOSCALE softkey 17 autozero 24 repeat 24 repeat timer 24 AUTOZRO softkey 24 AUX softkey 11 AUX esed doe s aM tart 1 11 UG 9 averaging 23 UG 14 commands QRG 9 iis saco eg Re Racer rius 2
120. 12 column 29 and print an appropriate message Line 360 Ifthe key code is 41 then softkey 8 was pressed Line 370 Move to row 12 column 29 print an appropriate message and go to the end of the program Line 380 Ifthe key code doesn t match any of the preceding codes another key was pressed In this case the key code has to be for softkey 5 6 or 7 key codes 14 38 or 40 since these are the only other keys that can interrupt the computer Line 390 Move to row 12 column 29 and print an appropriate message Line 400 of multi way branch Line 410 Return from subroutine Line 420 Define a subroutine that outputs commands to the analyzer Line 430 Perform error trapping Line 440 Return from the subroutine Running program 8 1 Clear the computer CRT and type in the program 2 Press ALT R S on the computer 3 Afterthe computer presets the analyzer and source it writes the softkey labels on the analyzer CRT The analyzer writes the first key label and blanks the other softkey labels Softkeys 5 6 and 7 remain blank becaus they are not given new labels 4 Press any key on the analyzer Pressing a softkey causes a message to be printed on the computer CRT Softkeys 5 6 and 7 generate an interrupt even though they weren t labeled No other keys of the analyzer generate an interrupt because of the SRQ mask specified Because the analyzer was left in remote mode it didn t respond to any keys
121. 1200 18 330 0 1500 800 1950 800 D 1950 1200 340 M 875 850 D 875 500 D 1200 500 350 M 1400 500 D 2050 500 D 2050 850 360 M 1200 400 D 1400 500 D 1200 600 D 1200 400 370 E 0 0 380 END Program 11 explanation Linel0 Assign an I O path to the address of the analyzer Line20 Assign an I O path to the passthru address of the analyzer Line30 Abort any transfers and clear the HP IB interface of the computer Line40 Clear the HP IB interface of the analyzer Line 50 Preset the analyzer and blank all the CRT display except the softkeys Define the CRT graphics as the target of passthru commands The graphics address is always one less than the analyzer s HP IB address Line 60 Initialize the graphics This sets a default line type scale and clipping limits in the computer Line 70 Define the analyzer CRT screen as the plot device and tell the computer that it is an HP GL Hewlett Packard Graphics Language device Line80 Scale the plotting area to the CRT screen allowing space for the softkeys The numbers are the corners of the CRT as described in the HP 8757C E Operating Manual Line90 Define the soft clip area to maintain a clean display Line 100 Erase all graphics pages Turn on graphics page 1 on to ensure that the graphics start there Line110 Select to plot with pen 3 the lowest intensity for the analyzer CRT Line120
122. 140 Set the format to binary and command the ana lyzer to output its channel 2 measurement trace Line150 Enter the measurement trace through the 1 O 10 path that suspends formatting This technique is useful for reading data from the analyzer at the highest possible speed Line160 Command the analyzer to accept the trace into its channel 2 memory Note the suppression of the normal carriage return line feed sequence by the K format If the cr If isn t suppressed the analyzer assumes the first data point is null Line170 Sendthe trace to the analyzer again through the 1 O path that suspends formatting Linel80 Temporarily stop program execution Line190 Setupaloop for all 401 measurement points read from the analyzer Line 200 Calculate an arbitrary function and fill the binary data array This function has no particular mean ing but represents some special calibration data such as a short open average Line210 End of the loop Line 220 Turn off channel 2 and command channel 1 to display the trace memory data Line 230 Set the format to binary redundant but good practice and command the analyzer to accept the following trace to channel 1 memory Again sup press the cr If sequence at the end of the line Line 240 Write the trace to the memory through the 1 O path that suspends formatting Line 250 Command the analyzer to autoscale the current display which is the memory trace just written Line 260 End progra
123. 2 inch ounces of torque is enough Making Connections GENERAL CONNECTION TECHNIQUE Align connectors carefully PRECISION 7mm CONNECTORS EXTEND CONNECTOR SLEEVE Make preliminary connection lightly Engage connector nut over exposed threads Turn connector nut only to tighten connection Light finger pressure lt 2 in ounces is enough Connectors only need to make uniform light contact Do not overtighten Figure 11 General Connection Technique Making Connections 25 26 Use a torque wrench to make the final connection When the preliminary connection has been made use a torque wrench to make the final connection Figure 12 Tighten the connection only until the break point of the wrench is reached when the wrench handle gives way at its internal pivot point Do not tighten the connection further Also make sure that torque actually is being applied to the connection through the torque wrench not only to the wrench handie or in any way that prevents the break point of the wrench from controlling the torque applied to the connection Suggestions are given below Using a torque wrench guarantees that the connection will not be too tight thus preventing possible damage to the connectors and impaired electrical performance It also guarantees that all connec tions will be made with the same degree of tightness every time they are made Torque wrenches pre set to the correct value for each
124. 200 OPTION BASE 1 DIM Lswpr 90 Lsna 150 ASSIGN Sna TO 716 ASSIGN Passthru TO 717 ABORT 7 CLEAR Sna OUTPUT Sna PT19 LOCAL Sna INPUT SET UP SYSTEM PRESS CONTINUE A OUTPUT GSna OL ENTER 5 USING 150A Lsna OUTPUT qPassthru OL ENTER Passthru USING 90A Lswpr OUTPUT qgSna IP INPUT TO RESTORE SETUP PRESS CONTINUE A OUTPUT Sna USING 2A 150A IL Lsna OUTPUT Passthru USING 2A 90A IL Lswpr OUTPUT Sna LOCAL Sna END Program 10 explanation Line 10 Line 20 Line 30 Line 40 Line 50 Line 60 Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Define the first element of any array to be at index number 1 Dimension two strings large enough to hold the learn strings of the source 90 bytes and the analyzer 150 bytes Assign an I O path to the address of the analyzer Assign an I O path to the passthru address of the analyzer Abort any transfers and clear the HP IB interface of the computer Clear the HP IB interface of the analyzer Tell the analyzer which device is controlled through the passthru address Address 19 belongs to the source Set the analyzer and source to local mode Prompt the user to set up the system and wait for the Continue key press Program the analyzer to output its learn string Read the analyzer learn string into the string Lsna Notice the 150A format The analyzer l
125. 240 PRINT Test 1 250 CASE 0 260 PRINT Calibration 2 270 CASE 16 280 PRINT Test 2 290 CASE 41 300 PRINT Abort measurement 310 GOTO 360 320 CASE ELSE 330 PRINT undefined 340 END SELECT 350 GOTO Wait_srq 360 END Program 8 explanation Linel0 Direct output to the CRT of the computer Line20 Assign an I O channel to the address of the analyzer Line 30 any transfers and clear the HP IB interface of the computer Line40 Clear the HP IB interface of the analyzer Line50 Preset the analyzer and source Line 60 Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Line 130 Line 140 Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260 Line 270 Line 280 Line 290 Line 300 Line 310 Line 320 Line 330 Line 340 Set the request mask to interrupt the computer whenever a softkey is pressed bit 3 See table 2 for the description of the status bytes Define the line that the computer will go to whenever it receives an interrupt Label softkey 1 with CAL 1 Softkey 1 is the softkey at the top of the CRT Label softkey 2 with TEST 1 Label softkey 3 with CAL 2 Label softkey 4 with TEST 2 Label softkey 8 with ABORT Line label for routine that waits for an interrupt Turn on the SRQ interrupts in the computer Wait for the interrupt in a tight loop If PAUSE were use
126. 6 ENT to set the address to 16 3 Insert the BASIC system disk into the disk drive of the computer and turn it on After a few seconds the computer displays BASIC Ready x x where x x is the BASIC version number 2 0 3 0 etc If you are using BASIC 3 0 4 0 or 5 0 you must also load the following binary BIN programs DISC C580 HPIB GRAPH ERR and IO using the LOAD BIN command Check out procedure 1 Press PRESET on the analyzer If the 8757 SYSTEM INTERFACE is properly connected and the address of the source correctly set both the analyzer and the source will perform an instrument preset If either instrument detects a failure during instrument preset that instrument displays the error encountered The operating manual of the source gives instructions to help you interpret the error message If the analyzer displays an error message see In Case of Difficulty 2 To verify the HP IB connections made between the analyzer and the computer perform these steps a Press SHIFT PAUSE to reset the computer b Type REMOTE 716 and press EXECUTE The R remote and L listen lights in the analyzer INSTRUMENT STATE area will light The analyzer has received its HP IB listen address Programming examples In the following sections example programs introduce the HP IB capabilities of the analyzer Each example program consists of these sections 1 Adescription of the functions exercised 2 The
127. 6 External disk Save Recail These external storage capabilities allow the user to increase productivity by concentrating on making measurements as opposed to repeatedly setting up the same instrument configurations Step six measure device under test After the test setup is calibrated and the device has been connected the trace displayed will present a normalized measurement of the device being tested Optimizing trace display To optimize the presentation of data the scale per divisions and or reference level and position may be adjusted Select ing SCALE displays the AUTOSCALE softkey which provides a quick convenient method for adjusting these functions SCALE also allows the user to change the scale per divisions by utilizing the keypad knob or step keys on the front panel Reference functions may be adjusted sepa rately by selecting REF LEVEL or REF POSN from the REF menu Changes may be entered via the keypad knob or step keys SWR and AUX display modes The HP 8757C E provides the user a choice of display for mats Reflection measurements may be displayed in standing wave ratio SWR or return loss dB The default format fol lowing preset is return loss To make measurements in the SWR format select TRC FMT SWR dB from the DISPLAY menu SWR is only available for channels 1 and 2 channels 3 and 4 have to be turned off on the HP 8757C The SWR measurement mode also requires a ratioed or nor mali
128. 61 Rear Panel Features 63 Operator s Check WHAT IS IN THIS REFERENCE Operating Reference This reference describes the operating features of the HP 8757C E Scalar Network Analyzer Front and rear panel features Front panel key operation Softkey operation Softkey menu structure maps e e 6 9 HP 8757C E Operating Reference M B The Operator s Check is located at the end of this reference to help you verify the functionality of the analyzer This document is intended to guide you through manual use of the analyzer Further instruction is contained in the User s Gu de which is included in this subsection Loca Operation The User s Guide describes general measurement setups and includes typical measurement examples See section 1 General Information for an overall description of the analyzer s capabilities EE HP 8757C ONLY GEI UEM CE EEC ECCO IX RM AM CRM M Text that applies only to the HP 8757C is enclosed with these symbols In a table text that is HP 8757C only is referenced to a footnote T es HOW TO USE THIS REFERENCE Figure 1shows the analyzer sfront panel Call outs identify the features which are described in the text below the figure Figure 2 is the CRT It identifies each of the information areas on the CRT To Find a Front Panel Key Descripti
129. 8 d 2 06655E 089 4 370 514 11 1 74725E 08 2 998 54 855 12 1 897 08 2 970 53 866 13 2 046751E 08 3 008 55 844 14 2 1965 08 3 038 59 211 Figure 22 Example Printout for PRINT DATA and b PRINT MKRS HP 8757C E Operating Reference 37 38 M M M M BP ONLY Je M MMM M if alternate sweep is on the printouts will include only the channel pair with the active channel channels 1 and 3 or channels 2 and 4 To print the other pair activate one of the channels in thal pair and print again ABORT PRINT terminates printing of a printout currently in progress Printing does not stop immediately it stops after the buffer empties PRIOR MENU returns the previous menu system menu Other SYSTEM functions TRACE POINTS presents a menu to choose the number of data points to be used by the analyzer for processing and showing the data on the CRT Selecting fewer points means lower resolution but lets you use faster sweep times M M M M MP 87570 ONLY emm MM M The maximum number of trace points available for each of four traces turned on simultaneously is 401 The maximum for two traces is 801 points The maximum for one trace is 1601 points using channel 7 only ERR NER ea ONCE RON ee ee eA e ee The analyzer presets to 401 trace points
130. 8757C E REAR PANEL POS 2 STOP BLANK 8350B REAR PANEL Figure 2 5 Analyzer to HP 8350B Sweep Oscillator Interconnections 2 10 Installation HP 8757C E 8757 HP INTERFACE gt SYSTEM INTERFACE BUS 8757C E REAR PANEL POS STOP SLANK SWEEP Z AXIS STOP SWEEP BLANK MKRS IN OUT Figure 2 6 Analyzer to HP 8340 and 8341 series Synthesized Sweeper Interconnections External Modulation The HP 8340 and 8341 series Synthesized Sweepers do not provide an internal 27 778 kHz modulated signal for use in AC measurements The HP 8350B Sweep Oscillator does However the analyzer s 27 778 kHz modulation signal can be used to externally modulate the synthesized sweeper Connect the modulator drive of the analyzer to the source according to the instructions given in table 2 3 CONNECTION FUNCTION indicates where to make the connection to the source front panel connector and which front panel key to press HP 8757C Installation 2 11 Table 2 3 External Modulation Connections Connection Function Connection Function without System with System Interface connected Interface connected HP 8340A Pulse Input Pulse Pulse input Pulse serial prefix lt 2302A HP 8340A AM Input Shift Pulse AM Input serial prefix 22320 HP 8341A AM Input Shift Pulse AM Input all serials HP 8340B Pulse Input Pulse Pulse input all serials HP 8341B Pulse Input Pulse Pulse Input all serials The correct function is progra
131. 8V typical 1 HP 8757 only HP 8757C E General Information 1 9 1 10 Table 1 2 Supplemental Performance Characteristics 1 of 3 Values in this table are not specifications but are intended to provide information useful in applying the instrument by giving typical but non warranted performance parameters DISPLAY CHARACTERISTICS Horizontal Resolution Number of Points 101 201 401 801 1601 Display Modes Allanalyzer channels can display any one ofthe detector inputs or any ratio combination of detector inputs Data can be displayed on the CRT in one of the following modes LOG MAGNITUDE dBm singie channel power measurement dB relative power measurement ratio or relative to trace memory SWR Relative measurements channels 1 and 2 only 401 points or fewer AUX The rear panel BNC input ADC IN can be measured and displayed in volts 10 to 10 volts Typical maximum error is 60 mV Display Scale Display Vertical Mode Resolution Range Resolution dBm 0 1 to 20 dB div 70 to 20 dBm 0 003 dB 1 2 5 sequence dB 0 1 to 20 dB div 90 to 90 dB 0 006 dB 1 2 5 sequence SWR 0 02 to 10 units div 1 0 to 37 0 See figure below 1 2 4 sequence AUX 0 025 to 5 V div 10 to 10 V 0 001 V 1 2 5 5 sequence SWR Resolution and Accuracy Datais converted to SWR using an internally generated look up table The resolution in SWR mode varies with the SWR being measured
132. A MEAS Key and Measurement Menus DISPLAY Key and Display Menus Color Adjustment Softkeys from Display Menus SCALE Key and Scale Menus HP 8757C E oor o9 o3 s poko 4 a Wok o o9 o O3 4 Fon A o t ov 4o 9 9o o son ov o3 o8 o o 3 oo 9o Fon s 9 ov a o NON o o9 4 3 o gt 4 4 ov om co vo o o o 9 3 3 Boro von Rogo 4 amar rawr n t o9 o3 won os ov o9 REF Key and Reference Menus 18 CURSOR Key and Cursor Menus 19 Key and Average Menus 21 CAL Key and Calibration Menus 22 SPCL Key and Special Menus 27 Knob STEP Keys and Numeric Keypad 30 INSTRUMENT STATE Keys 31 SYSTEM Key and System Menus 32 MUS see E SEN eed oS eae M 34 Print Menus y ice onn i d cote eee 36 Example Printout for PRINT DATA and PRINT o LOCAL Key and Local Menus gt 4 4 4 SAVE Key and Save Menus js RECALL Key and Recall Menus 47 PRESET Kay Loos ipo pe dp Seta sae tesa 50 HP IB STATUS indicators 5 58 Detector Inpu
133. AP AE The analyzer is locally operated by front panel controls and by menu selection using softkeys adjacent to the CRT The analyzer is programmable over the Hewlett Packard Interface Bus HP IB HP IB is Hewlett Packard s hardware software documentation and support for IEE 488 and IEC 625 world wide standards for interfacing instruments On screen graphics can be generated using a subset of Hewlett Packard Graphics Language HP GL See Remote Operation for a jist of commands and an example program 1 4 HP 8757C E General Information AC and DC Detection The HP 8757C E uses either AC or DC detection techniques in conjunction with its detectors The AC detection mode provides very stable measurements even with temperature variations and RF inter ference Use DC detection for modulation sensitive devices such as nonlinear amplifiers and narrow band filters and for devices that cannot be modulated such as oscillators In AC detection an RF or microwave signal is amplitude modulated with a 27 778 kHz square wave providing the stimulus to the device under test The output signal from the device under test is then detected by a compatible detector and the analyzer filters digitizes and displays the response on the CRT 27 778 kHz modulation signal is available from the rear panel of the analyzer to drive an external modulator for a source without internal amplitude modulation capability In DC detection an unmodulat
134. ASERR RETURN 240 250 260 270 280 230 300 310 320 330 340 350 360 370 Program 10 explanation Linel0 Call the QuickBASIC initialization file QBSETUP Line 20 Clear the computer CRT Line 30 Define the maximum number of characters for the analyzer learn string Line 40 Define the maximum number of characters for the learn string of the source Line50 Assign the interface select code to a variable Line 60 Assign the address of the analyzer to a variable Line70 Assign the passthru address of the analyzer to a variable Line80 Define a system timeout of 10 seconds Perform error trapping Line 90 Abort any HP IB transfers Perform error trapping Line100 Clear the HP IB interface of the analyzer Perform error trapping Line 110 Preset the analyzer and the source Line 120 Tell the analyzer which device is controlled through the passthru address Address 19 belongs to the source Line 130 Set the analyzer and source to local mode Perform error trapping Line 140 Prompt the user to set up the system Then wait for the ENTER key to be pressed Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260 Line 270 Line 280 Line 290 Line 300 Line 310 Line 320 Line 330 Line 340 Line 350 Line 360 Line 370 Disable character matching for the linefeed The analyzer learn string is 150 contiguous
135. ATUS OS command to determine the cause of the status change All other bits 7 5 4 3 1 0 of the status byte 1 indicate the present status of the noted function The bits are true one only if the associated function or condition is true Status bit The HP 8757C E does not respond to a parallel poll Controller capabilities The HP 8757C E does not have the ability to take or pass control Abort The HP 8757C E responds to the ABORT message interface clear line IFC true by stopping all listener or talker functions Self test A self test is performed at power up and whenever the instru ment PRESET IP command is received by the analyzer This self test routine includes a brief but thorough check that key parts of the instrument are functioning At the conclusion of the self test the analyzer will be placed in its PRESET condi tion The operator can check the outcome of the self test by reading bit 0 of the extended status byte 2 or by checking the front panel of the analyzer For details on checking the front panel after the self test refer to the Operating Reference Address assignment information The HP IB address for the analyzer is set at the factory to deci mal 16 The current address may be determined by pressing the LOCAL key on the front panel then selecting the 8757 softkey and observing the active entry area of the CRT It may be changed if desired by entering the digits range 00 t
136. Area 777777 CHANNEL SERA oo Bie elie i dom DDOE t sue E3 C f SP i INSTRUMENT STATE EJ C3 6 1 pem voee HPA STATUS 0000 The ENTRY area consists of the knob the STEP keys and the numeric keypad The knob is used to change current values for various functions such as SCALE and REF LEVEL Coun terclockwise rotation decrements the value clockwise rotation increments the value STEP The STEP keys are used to increment or decrement the numerical value of a function to the next allowed value T LO The numeric keypad is used to select digits decimal points and minus signs for numerical entries A termi mA ud em nator ENT or dBm dB is required except for SAVE cut ahd RECALL entries ENT OFF clears the active entry area on the CRT dam ENT terminates unitless entries 2 3 dB dBm dB terminates numeric keypad entries for func tions such as SCALE and REF LEVEL BK C BK SP deletes the last digit entered Figure 17 Knob STEP Keys and Numeric Keypad 30 Operating Reference HP 8757C E INSTRUMENT STATE Keys CHANNEL LJ CJ FUNC RON INSTRUMENT STATE RECALL 900 tU popped g g eer a RETIUM Figure 18 INSTRUMENT STATE Keys Figure 18 shows the INSTRUMENT STATE keys The keys in the INSTRUMENT STATE area of the f
137. C the adaptive normalization function needs to be selected prior to the selection of the CW frequency as shown below Source parameters SYSTEM Accesses system menu ADPT ON Activates adaptive normalization function SHIFT CW Enter desired frequency POWER LEVEL Set start power POWER SWEEP Enter sweep range Available only on the HP 8757C 16 Save Save the instrument states and calibration as previously described Measurement Reconnect the DUT Select channel 1 if itis not active The cursor function should be utilized to find the maximum point on the trace Then by activating the cursorA function the 1 dB point may be loca ted either by rotating the front panel knob or by utilizing the search function of the HP 8757C and changing the search value to 1 dB When the search function on the HP 8757C is used and the 1 dB compression point has been located selecting the cursor hardkey turns off the delta cursor func tion so that the absolute output and input power levels are presented in the mode label areas of channels 2 and 4 respec tively When using the HP 8757E simply turn off the cursor delta function by pressing the softkey to read the power levels Most HP 8350B RF plug ins in the power sweep mode can sweep up to 15 dB from the initial power set with POWER LEVEL If the 1 dB compression point cannot be found increase the power sweep setting or the start power Remember not to exceed
138. Create a permanent record of the measurement by plotting the results to a plotter or a printer via HP IB The plotter printer buffer facilitates efficient hardcopy outputs of your measurement data by releasing the analyzer to the user within 5 seconds Results may also be stored on an external disk the HP 8757C E allows the user to control these exter nal peripherals without connecting an external controller To obtain a hard copy output of the current display selecting PRINT or PLOT in the SYSTEM menu will offer a number of printing and plotting options displayed in the menus below SYSTEM HP 8757C HP 8757E 10 SYSTEM 8757C 8757E Lh ome a 1 PLOT ALL plots everything currently displayed except for the softkey menu and the number of points The user may also choose to plot only specific parameters i e PLOT TRACES or if repeated plots utilizing the same display parameters are necessary a custom plot may be specified DEFINE CUSTOM allows the user to select the display parameters for custom plots then selecting PLOT CUSTOM will output the results with the same for mat each time The SCALE TO 1 2 option in the DEFINE CUSTOM menu allows the user to expand the plot to fill up the page in this case the labels are plotted inside the grid In the HP 8757C E s PRINT menu GRAPH MONO allows the user to print the displayed information to any compatible printer in black and whi
139. D PA 1100 800 1100 1100 300 1100 300 800 GOSUB 1000 5 210 220 230 22 250 260 270 280 290 300 310 320 330 340 350 360 370 380 A PU PA 800 800 PD PA 800 1100 GOSUB 000 5 A PU PA 1500 800 PD PA 2300 800 2300 1200 1500 1200 1500 800 GOSUB 1000 5 A PU 1950 800 PD PA 1950 1200 6050 IO0QUTSP A PU PA 875 850 PD PA 875 500 1200 500 GOSUB IODUTSP A PU PA 1400 500 PD PA 2050 500 2050 850 GOSUB IO0UTSP A PU 1200 400 PD PA 1400 500 1200 600 1200 400 GOSUB IOQUTSP A PU PA 0 0 GOSUB IOQUTSP A GOSUB IOQUTS CALL IGLOCAL CSna amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR END IGDUTS CALL IOBUTPUTSCSna amp A LENCA 2 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR RETURN IOBUTSP CALL IOQUTPUTS CPassthru amp A LENCA IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR RETURN Program 11 explanation Line 10 Line 20 Line 30 Line 40 Line 50 Line 60 Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Line 130 Line 140 Call the QuickBASIC initialization file OBSETUP i Clear the computer screen Assign the interface select code to a variable Assign the address of the HP 8757C E toa variable Assign the passthru address of the HP 8757C E to a variable Define a system timeout of 10 seconds Perform error trapping Abort any HP IB transfers Perform error t
140. Digit CD is a coded digit that represents the specific combination of numbers used in the HP Part Number it should be supplied with the HP Part Number when ordering any of the power assemblies listed above to expedite speedy delivery 2 4 Installation HP 8757C E RACK MOUNTING CAUTION Use only the specified screws to install the rack mount kit Longer screws may damage internal components located behind the screw mounting holes Rack Mounting without Front Handies Option 908 Instruments with Option 908 contain a Rack Mount Kit This kit supplies the hardware and the installation instructions for preparing the instrument to mount on an equipment rack with 482 6 mm 19 in support spacing Installation instructions are also given in figure 2 2 Additional Option 908 Rack Mount Kits may be ordered See Replaceable Parts for ordering information Rack Mounting with Front Handles Option 913 instruments with Option 913 contain a Rack Mount Kit This kit supplies the hardware and the installation instructions for preparing the standard instrument with handles attached to mount on an equipment rack with 482 6 mm 19 in support spacing Installation instructions are also given in figure 2 3 Additional Option 913 Rack Mount Kits may be ordered See Replaceable Parts for ordering information HP 8757C E Installation 2 5 2 6 w Option 908 Installation Instructions Remove each front handie trim 1 by
141. E SMA AND PRECISION 3 5mm CONNECTORS Use male connector gage has circular bushing Mh SAN YS ay M Xx A NS amp w insert gage into connector 0 003in Male pin slips into gage plunger Figure 28 Gaging SMA and Precision 3 5mm Connectors 1 of 2 SMA and Precision 3 5mm Connectors FEMALE SMA AND PRECISION 3 5mm CONNECTORS Use female connector gage has no circular bushing Insert gage into connector 0 003in Plunger rests on end of female contact fingers Figure 28 Gaging SMA and Precision 3 5mm Connectors 2 of 2 SMA and Precision 3 5mm Connectors 69 70 Glossary Abort To cut short or break off an action operation or procedure Active Channel The highlighted channel that front panel functions will affect Address An identification as represented by a name label or number for a register location in storage or any other data source or destination such as the location of a station in a communications network or a device on the Hewlett Packard Interface Bus ALC An abbreviation for Automatic Level Control The process of monitoring and maintaining constant source power output Analog Of or pertaining to the general class of devices or circuits in which the output varies as a continuous function of the input Annotation The labeling of specific information such as frequency or power on the CRT Apert
142. EFT function except that the cursor CSR FMT SWR DB allows convenient readout of cursor data in SWR standing wave ratio when measuring device match in dB return loss if preferred The cursor formatis independent of the display format which determines the format of the entire trace CURSOR REF LVL changes the reference level value to be equal to the cursor reading The reference position is not changed so the trace moves to the reference level This makes it possible to expand the trace about the cursor for detailed viewing 20 Operating Reference HP 8757C E AVG AVERAGE MENUS FUNCTION HP 8757 Figure 14 AVG Key and Average Menus The AVG function averages a programmable number of sweeps Averaging computes each data point based on the average value during a specified number of sweeps The number of sweeps over which the trace is averaged is called the averaging factor The averaging technique is called stable averaging When averaging first begins the first sweep is averaged using an averaging factor 1 the second is averaged using an averaging factor 2 the third and fourth are averaged using an averaging factor 4 and increasing powers of 2 until the desired averaging factor is reached This technique improves accuracy and resolution in calibration or measurement traces Averaging is always per formed on logarithmic data When SWR format is engaged the SWR conversion is perfor
143. G Cursor vals 0 Max ActualZ IF PCIB ERR NOERR THEN ERROR PCIB BASERR Cur freq Start freq CStop freg Start freq Cursor vais 1 400 PRINT Cursor reads 5 Cursor vals 0 dB at Cur freq GHz END IGOUTS CALL IGOUTPUTSCSna amp A LENCA IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR RETURN IQOUTSP CALL IOQUTPUTS CPassthru amp AS LENCA TE IF PCIB ERR NOERR THEN ERROR PCIB BASERR RETURN Program 4 explanation Line 10 Line 20 Line 30 Line 40 Line 50 Line 60 Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Call the QuickBASIC initialization file OBSETUP Clear the computer CRT Define the start frequency of the desired sweep in GHz Define the stop frequency of the desired sweep in GHz Assign the interface select code to a variable Assign the address of the analyzer to a variable Assign the passthru address of the analyzer to a variable Define a timeout of 10 seconds Perform error trapping Abort any HP IB transfers Perform error trapping Clear the HP IB interface of the analyzer Perform error trapping Preset the analyzer and source This sets the number of points per trace to 401 Tell the analyzer which instrument is controlled through the passthru address 19 is the source Line 130 Line 140 Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260
144. H Places cursor markers on the 3 dB points of trace displays search value and bandwidth frequency span b T ee eee 20 1 T mw Lv STAT 49 22808545 star 2400z The search value and the bandwidth value are the same To change the bandwidth value select SEARCH SEARCH VALUE and enter the number on the keypad followed by ENT The user may also require frequency information at specific points Selecting MAX then CURSOR AON OFF SEARCH and SEARCH RIGHT or SEARCH LEFT will move the cursor to the search value previously set Then selecting CURSOR A ON OFF will display the frequency at that point Peak to peak ripple Measuring peak to peak ripple requires magnifying the passband such that the difference between the peaks can be determined SCALE Activates scale function 0 2 dBm dB Sets scale to 0 2 dB division CURSOR Activates cursor function MAX Moves cursor to maximum point on trace CURSOR AON OFF Marks the cursor position use the front panel knob to move the cursor to the minimum point on the trace the active entry area of the display will present the magnitude and frequency of the difference between the two points i i SIRT 45 24008Hz TASAA If more resolution is desired in the peak to peak measure ment the user may zoom in on the passband by selecting channel 2 then repeating the general measurem
145. HP 8757C E SCALAR NETWORK ANALYZER OPERATING MANUAL SERIAL NUMBERS This manual applies directly to any HP 8757C Scalar Network Analyzer having serial number prefix 3026A and any HP 8757E Scalar Network Analyzer having a serial number prefix 3025A For instrumenis with lower serial number prefixes see section 7 Manual Backdating 2 For additional information about serial numbers refer to Instruments Covered By Manual in Section 1 Copyright HEWLETT PACKARD COMPANY 1400 FOUNTAINGROVE PARKWAY SANTAROSA CA 95403 MANUAL PART NO 08757 90073 Printed JUNE 1991 Part of HP Part Number 08757 90067 Edition 3 HEWLETT LA NN RA CERTIFICATION Hewlett Packard Company certifies that this product met its published specifications at the time of shipment from the factory Hewlett Packard further certifies that its calibration measurements are traceable to the United States National Bureau of Standards to the extent allowed by the Bureau s calibration facility and to the calibration facilities of other International Standards Organization members WARRANTY This Hewlett Packard instrument product is warranted against defects in material and workmanship for a period of one year from date of delivery During the warranty period Hewlett Packard Company wili at its option either repair or replace products which prove to be defective For warranty service or repa
146. HP IB The analyzer exerts control over a source HP 8350B 8340B 41B or 8360 digital plotter HP 7440A or 7550A and printer HP 2225A ThinkJet HP 3630A PaintJet or HP 2227B QuietJet Plus connected to the 8757 SYSTEM INTERFACE This note assumes you are familiar with local non remote operation of the HP 8757C E If not refer to the operating manual You should also be familiar with the HP Vectra 75 Personal Computer or compatible particularly HP IB j operation using the HP 82335A Command Library Microsoft is a U S registered trademark of Microsoft Corp The following are sample programs included in this guide Program 1 Remote Local and Local Lockout Program 2 Controlling the Front Panel Program 3 Passthru Mode Program 4 Cursor Operations Program 5 Read a Single Value e Program 6 Trace Transfer Program 7 Using the TAKE SWEEP Command Program 8 Programming the Softkeys Program 9 CRT Graphics Program 10 Learning the Instrument State Program 11 Guided Instrument Setup with CRT Graphics Reference information The following texts provide additional information on the HP Interface Bus analyzer source and HP Vectra Personal Computer HP 8757C E literature HP 8757C E Operating Manual Programming Note Quick Reference Guide for the HP 8757C E Scalar Network Analyzer Source literature Programming Note Quick Reference Guide for the HP 8350B Sweep Os
147. HP IB interface to detect HP IB service requests and process the interrupt as ON PEN events Line label for routine that is executed when an interrupt is detected Enable HP IB service request interrupt event trapping Line label for routine that waits for an interrupt If the last softkey pressed was not the Abort key softkey 8 key code 41 continue looping Disable HP IB service request interrupt event trapping End program execution Line label for routine that services the interrupts Serial poli the analyzer Reading the status byte of the analyzer clears the SRQ The CLEAR STATUS CS command could also be used Perform error trapping Command the analyzer to output the key code of the last key pressed Read the key code Line 280 Multi way branch on key code value When lines are labeled with numbers in QuickBASIC SELECT CASE CASE for the first case must occur on the same line and be separated by a statement separator If the key code is 32 then softkey 1 was pressed Line290 Moveto row 12 column 29 on the computer CRT and print an appropriate message Line300 Ifthe key code is 8 then softkey 2 was pressed Line310 Move to row 12 column 29 and print an appropriate message Line320 If the key code is 0 then softkey 3 was pressed Line330 Move to row 12 column 29 and print an appropriate message Line340 Ifthe key code is 16 then softkey 4 was pressed Line350 Move to row
148. IPLES OF Type N Connectors CONNECTOR CARE Figure 18 Type N Connectors 47 Figure 1 Handling and Storage 4 Figure 19 Approximate Effects of Contact Figure 2 Electrostatic Discharge 5 Separation on Reflection Coefficient Type N Figure 3 Recommended CORBSCIOIS oui et sen EL VE deaf 48 Cleaning Supplies 9 Figure 20 Gaging Type N Connectors 50 Figure 4 Cleaning Microwave Connectors 11 Figure 5 Cleaning interior Surfaces and SMA and Precision 3 5mm Connectors Precision 7mm Connectors 13 pe Figure 21 SMA Connectors 55 p 2 cee a ee i Figure 22 Precision 3 5mm Connectors 57 Figure 8 SMA Connectors es 18 Figure 23 Precision 3 5mm Connector and Figure 9 Precision 8 5mm Gonneetors NDA 18 Precision 3 5mm SMA Connector Interfaces 59 Fi ee Figure 24 Typical SWR of Precision 3 5mm and igure 10 Zeroing the Connector Gage 21 SMA Coupled Junctions 60 Figure 11 General Connection Technique 25 Figure 12 Using the Torque Wrench 27 Figure 25 3 5mm Adapters 62 GPCR NU TEM n tst Figure 26 Typical Directivity Using Connector Saver Adapters 64 F to Precision 7mm Adapters 65 Precision 7mm Connectors Figure 28 Gaging SMA and Precision Figure 13 Precision 7mm Connector 33 3 5mm Connectors 68 Figure 14 Ce
149. ISPLAY COLOR MORE GREEN CHROME ge PRIOR PRIOR MODY o MENU MENU COLOR LFA ar mt fon EH T H 3 Figure 10 Color Adjustment Softkeys from Display Menus ftu i NOTE Although you have the option to adjust the colors of allthe CRT attributes itis possible to Setting Default Colors To set all the CRT attributes to the factory defined default colors press SF LAY ADJUST DISPLAY DEFAULT COLORS N OAE th a aC RE cr ETE HP 8757C E Operating Reference 15 16 87876 ONLY Changing CRT Attribute Colors To change the color of a CRT attribute press the softkey for that attribute such as CHAN 1 COLOR or GRID The menu containing the color list is presented The current color for the attribute is highlighted and underlined Choose one of the seven available colors by pressing the desired color Selection of the color returns you to the menu from which you came If you don t wish to choose one of these colors press any front panel key except for ENTRY keys to exit this menu Setting Monochrome To set your CRT to green monochrome press DISPLAY ADJUST DISPLAY MORE MONOCHROME All of the CRT attributes are now green A highlighted box surrounds the active mode labels and all attributes associated with the active channel are highlighted Adjusting Colors If the default colors or t
150. Knob activity instrument self test error 1 HP 8757C only HP 8757C E General Information Lil 1 12 Table 1 2 Supplemental Performance Characteristics 3 of 3 SYSTEM INTERFACE Description The 8757 System Interface is a dedicated HP 1B port used exclusively by the analyz er to control and extract information from a swept source digital plotter printer or other devices GENERAL SPECIFICATIONS Temperature Range OPERATING 0 to 55 C 32 to 131 STORAGE 40 to 70 C 40 to 158 Power Requirements 48 to 66 Hz 100 120 220 240V 10 typically 155 VA Dimensions 178 x 425 x 445 mm 7 0 x 16 75 x 17 5 in Does not include handles Weight NET 22 kg 48 Ib SHIPPING 28 kg 61 5 Ib General Information HP 8575C E Section 2 Installation CONTENTS 1 Introduction 1 Initial inspection 2 Preparation for Use 5 Rack Mounting 8 HP INTERFACE BUS and 8757 SYSTEM INTERFACE Connectors and Cables 10 Analyzer to Source Interconnections 12 Analyzer to External Monitor Interconnections 13 HP IB Address Selection 14 Operating Environment 14 Storage and Shipment Environment 14 Packaging INTRODUCTION This section provides installation instructions for your HP 8757C E Scalar Network Analyzer and its accessories This section also includes information about initial inspection damage claims prepara tion for using the analyzer packaging storage and shipment Text that applie
151. LIZATION ON SYSTEM uncalibrated 1 HP 8757C Mode labels are shown for each channel in the following locations LEFT SIDE OF CRT RIGHT SIDE OF CRT Channel 1 Channel 2 Channel 3 Channel 4 The active channel mode labels are enclosed in a highlighted box HP 87576 ONLY M ___ _ __ 2 PASS FAIL INDICATORS These labels show the pass fail status based on the limit lines entered for channel 1 or 2 The pass fail indicators can be shown only with both channels 3 and 4 off 3 SOFTKEY LABELS The softkey labels define the functions of the softkeys for the menu shown Labels for functions engaged for the active channel are shown with greater intensity and underlin ing 4 TITLE LINE This line shows the title which you can enter using the SYSTEM menu 9 ACTIVE ENTRY AREA The last entry or HP IB command function selected is shown here Exceptions are PRESET MEAS and DISPLAY MESSAGE LINE This line shows messages and warnings to the operator REFERENCE LINE POSITIONS The reference position for each channel is identified by the number of the channel and a gt symbol in the left margin of the graticule grid Reference lines can only be positioned on major graticule lines 8 DATA DISPLAY AREA The measurement data traces are shown in this area simultaneously for all channels that are turned on 9 FREQUENCY LABELS The start stop and cursor or so
152. LS Accesses labels menu FRQ LBLOFF Deactivates frequency annotation on the analyzer and the source To disable the frequency blanking function select PRESET A T E N D I X AC versus DC detection There are two methods used to detect microwave signals for display and measurement with scalar network analyzers AC detection uses a modulated RF signal providing accurate and stable measurements by minimizing unwanted signals DC detection which utilizes an unmodulated RF signal is most useful for modulation sensitive devices This section describes the capabilities and advantages of each mode For further information on AC DC detection with scalar ana lyzers refer to Product Note 8757 1 Using AC detection with the HP 8757 scalar network analyzers The AC detection mode uses a 27 778 kHz square wave modulated source The square wave is demodulated by the detector and only the modulated envelope is passed to the scalar analyzer At the analyzer the demodulated signal is AC coupled into the log amplifiers then digitized There are four main benefits of AC detection in scalar network meas urements 1 high leveled broadband noise is rejected 2 undesired RF signals are not detected 3 thermal effects are minimized and 4 fast sweep times are possible even at low power levels The DC detection mode does not require any source modu lation the detectors respond to all the signals present The HP 85025 and 85026 se
153. N OFF allows you to turn on or off graphics that have been recalled from disk or placed in graphics memory by computer GRAPHIC ONT shows graphics and softkey menus only and blanks all instrument state and measurement data The current softkey menu remains active on ihe CRT and ail other softkey menus can be accessed A useful application for this function might be an instrument connection diagram which a user can access at any time during the measurement process GRAPHIC OFF turns off graphics and returns the instrument state and measurement data PRIOR MENU returns the previous menu SELECT CHAR enters your character selection Turn the analyzer knob until the arrow points to the character you desire Press SELECT CHAR and the character appears in the title area BACKSPACE deletes the last character entered in the title ERASE TITLE deletes the entire title STP ONE RIGHT moves the arrow pointer to the next character to the right STP ONE LEFT moves the arrow pointer to the next character to the left DONE terminates entry of the title and returns the previous menu NEXT PAGE shows you successive pages of the directory PREV PAGE shows you previous pages of tne directory SELECT TITLET lets you select a file title to be the active file title The current active file title is shown atthe top of the CRT Use the analyzer knob to move the arrow to the file title you wish to be the active file title Press SELECT TITLE
154. NDUCTOR MATING PLANE PROTRUSION i COLLET Figure 6 Precision 7mm Connector Mechanical Inspection 15 16 Type N Connectors Type N connectors differ from other connector types in that the outer con ductor mating plane is offset from the mating plane of the center conductors Figure 7 The outer conductor sleeve in the male connector extends in front of the shoulder of the male contact pin When the connection is made this outer conductor sleeve fits into a recess in the female outer conductor behind the piane defined by the tip of the female contact fingers in Type N connectors the position of the center conductor in the male connector is defined as the position of the shoulder of the male contact pin not the position of the tip The male contact pin slides into the female contact fingers and electrical contact is made by the inside surfaces of the tip of the female contact fingers on the sides of the male contact pin Hence the critical mechanical specifications of Type N connectors are a maximum protrusion of the female contact fingers in front of the outer conductor mating plane and a minimum recession of the shoulder of the male contact pin behind the outer conductor mating plane As Type N connectors wear the protrusion of the female contact fingers generally increases due to wear of the outer conductor mating plane inside the female connector This decreases the total center conductor contact separation and should
155. NECTORS Use adapters to reduce wear on connectors that may be difficult or expensive to replace Use adapters to change the connector interface Use adapters whenever devices that have SMA connectors must be measured Adapters are used to connect devices with one connector interface to a device or to test equipment that has another interface or to reduce wear on connectors that may be difficult or expensive to replace Adapters are often used to connect devices that have Type N precision 3 5mm or SMA connectors to test instruments that have precision 7mm connectors They are also used to minimize connector wear especially when the devices under test have SMA connectors Figure 17 shows the adapters that are recommended for converting a precision 7mm interface to various other interfaces When an SMA interface is desired use an adapter that has a precision 3 5mm interface Precision 3 5mm connectors are compatible with SMA connectors There are no separate 7mm to SMA adapters Using adapters is strongly recommended whenever devices that have SMA connectors must be measured SMA connectors are low cost connectors and are not precision mechanical devices They are not designed for repeated connections and disconnections they wear out quickly and they are very often found upon assembly to be out of specification even before they have been used This makes them potentially destructive to any precision 3 5mm connectors with which they m
156. NOT FOUND will appear in the ACTIVE ENTRY AREA Cursor FRO Cursor format logarithmic dB ordBm 7 Format 1 Cursor format SWR Averaging AQ Averaging off AFd Averaging on and factor set to d d is 0 enables previous factor 1 2 4 8 16 32 64 128 or 256 Restart averaging process on the next sweep DC Detector Zero Manualzero of the DC detectors The operator must turn the source RF power off before sending this command AZm Auto Zero Repeat on off of the DC detectors The source RF poweris automatically turned off at an interval determined by the Repeat Auto Zero Timer and the DC zero is performed each time AZ2 Auto Zero of the DC detectors Thesource RF power is automaticaly turned off and the DC zerois performed once ZTd Repeat Auto Zero Timer interval set to d d is a decimal integer from 1 to 60 minutes Smoothing SOd 3 Set Smoothing tod of spar d must be in the range of 0 0 to 20 0 with a maximum resolution of 0 1 When d is set to 0 this is equivalent to smoothing off Step UP 1 Step up increment the active parameter DN 1 Step down decrement the active parameter 1 HP 8757E only e 2 Revision 3 1 or above for an HP 8757C revision 4 1 or above for an HP 8757C 13 Available only if display trace data is in log magnitude format see 050 4 This command is valid only when the operator is using a source which is connected to the 8757 SYSTEM INTERFACE Table1 Function Sel
157. NT changes the attribute s hue This parameter is adjusted the same way as COLOR 5 Color changes and adjustments remain in effect until changed again in these menus Preset and power on off do not affect color selection To return to a previously defined color write down the numeric value of the color brightness color and tint and enter those values for each of the parameters M RR Operating Reference HP 8757C E SCALE SCALE MENUS FUNCTION HP 8757C E Figure 11 SCALE Key and Scale Menus The SCALE key engages the SCALE FACTOR function SCALE FACTOR lets you select the scale per division for viewing measurement data The possible choices for each of the display modes are shown in table 4 You can change the scale factor with the knob the STEP keys or the numeric keypad If the keypad is used to enter the scale factor the entry must be terminated with the dBm dB or ENT key The SCALE key also presents the scale menu The only label in the scale menu is AUTOSCALE Pressing AUTOSCALE automatically adjusts the scale and reference level of the active trace so that it best fits within the graticule Table 4 Scale Per Division for Display Modes Display Available Scales Per Division Mode dB dBm 20 10 5 1 0 5 0 2 and 0 1 per division 10 4 2 1 0 4 0 2 0 1 0 04 and 0 02 SWR units per division SWR AUX ADC
158. P is used to output the current P1 and P2 positions P1 is the lower left position and P2 is the upper right position The graphics display units GDU s define the plotting area on the CRT The coordinates of the full page have changed to reflect the new displays used in the HP 8757C E The coordinates are shown in table 1 Table 1 Full Page Coordinates of the HP 8757C E Display Lower Left Upper Right Trace Graticule _ HP 8757A 0 0 2698 2047 198 150 23071814 HP 8757C E 0 0 2924 2047 214 150 2500 1814 4 The SELECT PEN command SP n is used to select the beam intensity and color to be displayed on the CRT The SELECT PEN command operates in three different modes Monochrome display Color HP 8757C only e HP 9000 series 200 300 BASIC color HP 8757C only The monochrome display mode set by the DF command uses the SP n command to select between three different beam intensities and beam off The color mode is selected if it is not already on by using the HP 8757C DEFAULT COLORS command DEC To determine the colors associated with the different pen numbers see table 4 of the quick reference guide The third mode is the color mode used in HP BASIC and is set by using the HP 8757C BASIC COLORS command BO For a list of the colors available see table 4 of the quick reference guide or the BASIC 5 0 Condensed Reference Unknown Commands The HP 8757A has some commands ava
159. P IB address While in the passthru mode the analyzer stops updating its CRT and does not respond to its front panel because it s in remote mode To remove the analyzer from passthru mode simply address it via HP IB While in passthru mode do not press LOCAL on the analyzer The analyzer s passthru address is calculated from its HP IB address If the address of the analyzer is even such as 16 decimal then the passthru address is the next larger number 17 decimal If the address of the analyzer is odd such as 15 decimal then the passthru address is the next smaller number 14 decimal Never set the address of the analyzer such that its address conflicts with one of the instruments connected to the 8757 SYSTEM INTERFACE For instance if the source is set to 19 decimal do not set the address of the analyzer to 19 Data can be sent to or received from any instrument on the 8757 SYSTEM INTERFACE via passthru mode LOCAL REMOTE and TRIGGER HP IB messages do not pass through the analyzer Program 3 listing 10 PRINTERIS1 20 ASSIGN Sna TO 716 30 ASSIGN Passthru TO 717 40 ABORT7 50 CLEAR Sna 60 OUTPUT gGSna IP 70 OUTPUT GSna PTI9 80 OUTPUT qgPassthru OPFA 90 ENTER Passthru Min_freq 100 Min_freq Min_freq 1E 9 110 OUTPUT Passthru OPFB 120 ENTER Passthru Max_freq 130 Max_freq Max_freq 1 E 9 140 OUTPUT 5 150 PRINT Frequency limits Min freg to Max freq GHz INPUT Start
160. P O TWISTED PAIR WITH 7 P O TWISTED PAIR WITH 6 7 L REN L 0108 L 0107 L DI06 L 0105 HP IB Logic Levels True low State 0 8 VDC high State gt 2 4 VDC CONNECTED TO EARTH GROUND SHIELD L ATN SRO L IFC 7 LNDAC L oo L DAV L EO L 0104 L DIO3 L 0102 L DIO1 2 1 9 9 8 7 6 5 4 3 2 1 NOTE Mnemonics on the wiring list for J1 and J2 are coded B A to differentiate between the two L BDIOS 8757 System Interface L ADIOS HP Interface Bus MNEMONICS TABLE L L DAV L DIO1 through 8 L EOI L NDAC NRFD L REN L SRQ LOW Attention contro line LOW Data Valid control line LOW Data Input Output lines LOW End Or Identify control line LOW interface Clear control line LOW Data Not Accepted control line LOW Not Ready For Data control line LOW Remote Enable control line LOW Service Request control line Figure 2 4 8757 SYSTEM INTERFACE Connector and HP INTERFACE BUS Connector Signal and Pin Configuration HP 8757C E Installation 2 9 ANALYZER TO SOURCE INTERCONNECTIONS An RF or microwave source is required for use with the analyzer The 8350B Sweep Oscillator and the HP 8340 and 8341 series Synthesized Sweepers are commonly used sources The following setups figures 2 5 and 2 6 show the interconnections between these sources and the analyzer 8757 HP INTERFACE SYSTEM INTERFACE BUS
161. Plotagrid on the CRT These are 100 by 100 squares giving you an indication of where the X and Y coordinates are on the CRT Line130 Select to plot with pen 1 the brightest intensity for the analyzer CRT Line 140 Define where to start looking for data Here we ve indicated that the data starts at the line label Graphix which is line 280 This ensures that we always start at the right data statement Line150 Define the beginning of a loop Line160 Read three items from the data statement Pen mode is a one character string indicating whether we should move draw D or end E the plotting X and Y are the plot coordinates Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260 Line 270 Line 280 Line 290 Line 300 Line 310 Line 320 Line 330 Line 340 Multi way branch on the Pen_ mode value If Pen_mode is D then we want to draw Draw to coordinates X Y If Pen mode is M then we want to move Move to coordinates X Y End of multi way branch End of the repeat loop Repeat lines 160 through 220 again if Pen mode isn t E If it was then we are finished plotting the data in the data statements Move the pen to title our display Title the display with the label CONNECTION DIAGRAM This shows one way to label the analyzer display by using its internal character set To do this we must first specify which set to use via the
162. Port An input or output point of a circuit or device Preset 1 A pre defined instrument state which also runs a self test in the analyzer 2 The action of pushing the PRESET key Raster The process of drawing on the CRT by deflecting the electron beam rapidly from left to right and relatively slowly from top to bottom Reflection The phenomenon in which a traveling wave that strikes a discontinuity is returned to the original medium Remote A mode of operation where an instrument is controlled by another device or computer via the HP IB In this mode the instrument front panel keys are disabled Return loss The ratio expressed in dB between power incident upon and power reflected from a device Calculated as 20 where p is the reflection coefficient in magnitude HP 8757C E Glossary RPG 1 An abbreviation for Rotary Pulse Generator 2 The analyzer front panel knob Saturation The degree of purity of a color A scale from white to pure color Scalar 1 A quantity that has magnitude but no phase 2 A network analyzer that is capable of measuring magnitude only Seif test A group of tests performed at power up or preset that verify proper instrument operation Softkey A key whose function is defined by the current instrument state Source A device which supplies signal power Used in this document to refer to sweep oscillators or synthesized sweepers Sweeper A signal source that outputs a signal whic
163. Press Continue 7 The reference position line is set to the center of the CRT graticule 4 The top of the CRT is graticule 8 and the bottom is graticule 0 Press Continue 8 Change the measurement to reflection input A instead of transmission input B At preset channel 2 defaults to input B Press Continue 9 none statement turn off channel 2 turn on channel 1 set the scale per division to 5 dB set the reference position line to the center of the CRT and set the reference level to 5 dBm NOTE The semicolon terminators are needed after any analyzer command that can have a variable length Extra terminators never hurt so use them liberally Program 3 passthru mode In normal operation the system source digital plotter printer and disk drive HP 8757C only are connected to the 8757 SYSTEM INTERFACE This connection allows the analyzer to control and extract information from the other parts of the measurement system To allow you to control the source and plotter with the computer the analyzer has a built in PASSTHRU command that takes a command from the computer and passes it on to one of the instruments connected to the 8757 SYSTEM INTERFACE To initiate passthru mode first tell the analyzer which instrument you wish to command by setting the passthru address Then to talk or listen to that device address the analyzer s special passthru HP IB address which is different from the analyzer s H
164. R THEN ERROR PCIB BASERR A FD3 C1WM GOSUB 100075 CALL IOQUTPUTB Sna amp SEO Binary dat 1 Max2 12 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR CALL IGEOLCISC amp CHR C132 CHRSC10 22 IF PCIB ERR lt gt NGERR THEN ERROR PCIB BASERR 460 A AS GOSUB IO0UTS 470 END 480 IODUTS CALL IOOUTPUTSCSna amp AS LENCA 2 490 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 500 RETURN Program 6 explanation Linei0 Call the QuickBASIC initialization file QBSETUP Line20 Clear the computer CRT Line 30 Assign the interface select code to a variable Line 40 Assign the address of the analyzer to a variable Line50 Dimension an array to hold a trace of 401 points in ASCII format Dimension a second array to hold another 401 points trace in binary format Line 60 Create a variable based on the number of points per sweep on the analyzer By using a variable here it helps to make the program easily adaptable to different numbers of trace points Line 70 Create a variable to define the number of bytes used in the binary trace transfer Line 80 Define a system timeout of 10 seconds Perform error trapping Line 90 Abort any HP IB transfers Perform error trapping Line 100 Clear the HP IB interface of the analyzer Perform error trapping Line 110 Preset the analyzer and the source This sets the number of points per trace to 401 Line 120 Set channel 1 to reflection input A and channel 2 to transm
165. S BRIDGE FILTER HP VECTRR KONEEN 4 PERSONAL COMPUTER I Figure 1 System Connections remote local and local lockout The analyzer may be used with the front panel local oper ation or programmed via HP IB remote operation The programmer of the instrument system has control over the operation of all instruments in the system When the computer first addresses an instrument the instru ment is placed in a special remote operating mode called remote mode When in remote the instrument does not respond to its front panel except for the LOCAL key LOCAL when pressed cancels the remote mode and allows the instrument to be used with its front panel The computer can also return the instrument to local opera tion To do so the computer sends a special command that forces the instrument to go to local mode 1 HP 8757C only 2 HP 8757C Option 001 only Occasionally the programmer of an automatic system needs to prevent the instrument operator from returning the instru ment to local operation via LOCAL When the local lock out function of the computer is used the instruments are prevented from exiting remote mode even when LOCAL is pressed Frequently the programmer needs to place the instruments connected to the computer into a known state When preset the analyzer defaults to the conditions shown below The instrument preset function operates the same as the front panel PRESET key on the ana
166. S MEM Step five save instrument state Utilize the HP 8757C E s internal memory or an external disk drive HP 8757C only to save recall the instrument configuration and calibration This step will save time and effort when reconfiguring frequently used measurement set ups or recalling a configuration that was lost after inadver tently pressing PRESET or cycling the line power Internal storage The SAVE and RECALL keys are used to store and retrieve up to nine complete front panel states of the analyzer and the source if the 8757 System Interface is connected Color selections on the HP 8757C may not be saved inter nally but may be stored on a disk Only registers 1 through 4 may store the calibration memory limit lines and titles from channels 1 and 2 along with the instrument states Informa tion may be stored or retrieved internally by selecting SAVE or RECALL then the number of the storage regis ter The instrument states are saved in a non volatile memory and will not be erased until written over or until the CLEAR SAV RCL softkey is utilized from the SYSTEM menu External storage HP 8757C only A permanent copy of the instrument configuration and calibration may be made utilizing the external storage capa bilities of the HP 8757C and an external disk drive The SAVE and RECALL functions access the external storage menus as well as the internal storage registers For more information refer to chapter
167. S will be seen the minimum directivity is typically 34 dB when 7mm to 3 5mm adapters are used with an HP 85021 27A directional bridge The minimum directivity is also 34 dB when 3 5mm to 3 5mm adapters are used with an HP 85021 27B bridge but these bridges are usable up to 26 5 GHz Ee 7 5 gt ke 30 BRIDGE WITH CONNECTOR SAVER TYPICAL eas 35 E n uM s UU EIE IACTA NE 5 a usur 40 45 c 01 2 18 20 6 5 FREQUENCY GHz Figure 26 Typical Directivity Using Connector Saver Adapters SMA and Precision 3 5mm Connectors Special 3 5mm F to Precision 7mm Adapters One special use of adapters should be noted In order to produce a 7mm interface on the 3 5mm test ports of the HP 8513A and HP 8515A test sets for example to use 7mm calibration or verification devices or the HP 85041A transistor test fixture with these test sets the adapters in the HP 85130A special 3 5mm F to 7mm adapter kit should be used at the test ports instead of any other adapters The adapters in the HP 85130A special adapter kit have two special features 1 the 3 5mm side is a special NMD 3 5 connector designed specifically to mate with HP 3 5mm test ports and 2 the 7mm side has a center conductor setback that is the same as the setback on HP 7mm test ports Thus the 7mm interface that results is the same as is found on test sets with 7mm connectors Other adapters may be used at non
168. SCH string of up to 50 characters External detector cal vlaue for detector A External detector cal value for detector B External detector cal value for detector C External detector cal value for detector R J 1 HP 8757C only 2 HP 8757C Option 00 only detector C 3 Limit line functions valid only for channels 1 or 2 HP 8757C only NOTES decimal integer 1 to 9 variable length numeric 0 for off 1 for on unique value ASCH or binary string Eg og oO 5 23 For more information call your local HP sales office listed in your telephone directory or an HP regional office listed below for the location of your nearest sales office United States Hewlett Packard Company 4 Choke Cherry Road Rockville MD 20850 301 670 4300 Hewlett Packard Company 5201 Tollview Drive Rolling Meadows 60008 312 255 9800 Hewlett Packard Company 5161 Lankershim Blvd No Hollywood CA 91601 818 505 5600 Hewlett Packard Company 2015 South Park Place Atlanta GA 30339 404 955 1500 Canada Hewlett Packard Lid 6877 Goreway Drive Mississauga Ontario L4V1M8 416 678 9430 Australia New Zealand Hewlett Packard Australia Ltd 31 41 Joseph Street Blackburn Victoria 3130 Melbourne Australia 03 895 2895 Europe Africa Middle East Hewlett Packard S A Central Mailing Department Box 529 1180 AM Amstelveen The Netherlands 31 20 547 9999 Far East
169. SI command This specifies the width and height respectively of each character and is similar to the computer s CSIZE instruc tion We indicate what the label is with the LB command and follow it with the label We must terminate the label with an end of text ETX character a byte equal to a binary 3 Move the pen to label our device under test DUT Label the DUT using the computer s LABEL statement Notice the difference between this label and the one generated in line 250 First the intensity is less Second the characters look more round and smooth This is because the computer generates each character by plotting several smail strokes more than the HP 8757C E s internal CRT does for its characters This means that you will also use much more graphics memory than with the internal character set Set the analyzer and the source to local mode Define the start of the data statements containing our plotting information for all of the lines on the CRT While these may be less legible than lots of MOVEs and DRAWS it is more efficient programming This data statement draws the outline of the sweeper This data statement draws the plug in in the sweeper This data statement draws the outline of the analyzer This data statement draws the CRT of the analyzer This data statement draws the connections from the sweeper to the DUT Line 350 This data statement draws the connections from the DUT to the analyzer
170. T FINGERS OUTER CONDUCTOR MATING PLANE Figure 18 Type N Connectors OUTER CONDUCTOR MATING PLANE Type N Connectors 47 48 Electrical Effects of Contact Separation Type N connectors are often usable in many applications even when the total separation between the shoulder of the male contact pin and the tip of the female contact fingers exceeds the maximum implied by the mechanical specifications Figure 19 shows the approximate effects of total contact separation on the reflection coefficient of Type N connections As can be seen at lower frequencies the effects even of fairly wide total contact separations are smail Only at higher frequencies does contact separation become important e o Z o ui E CONTACT SEPARATION INCHES Figure 19 Approximate Effects of Contact Separation on Reflection Coefficient Type N Connectors Type N Connectors Gaging Type N Connectors A single gage that has separate bushings for male and female connectors is used to gage Type N connectors A connector gage kit containing all of the items required is available as HP Part Number 85054 60024 Male Type N Connectors To gage male Type N connectors Figure 20 first attach the bushing for male connectors to the dial indicator assembly Slip the bushing over the gage plunger assembly on the gage and fasten it there using the two Allen screws in the bushing The outer end of
171. T softkey presents the print menu When one of the print softkeys is pressed the analyzer freezes the data to be printed on the CRT and sends itto the printer through a buffer Once the data is transferred to the buffer the analyzer is free to continue measurements while the data is printing If the printer is incorrectly addressed or not connected to the 8757 SYSTEM INTERFACE the message NO PRINTER AVAIL appears on the CRT Once the problem has been corrected press the print softkey again to begin printing If the printer is properly connected to the 8757 SYSTEM INTERFACE but has no paper loaded or is otherwise not ready to print the message PRINTER NOT READY appears on the CRT Once the problem has been corrected press the print softkey again to begin printing GRAPH MONO causes the printer to draw the grid labels trace data cursors markers and title Messages in the active entry area and most SofKoys are not included Use this command to print in black and white mode only Operating Reference HP 8757C E S a GRAPH COLOR causes the printer to draw the grid labels trace data cursors markers and title Messages in the active entry area are not included Use this command to print color only PaintJet Printer The printer will print with a default set of colors which approximate the default colors of the analyzer with white and black reversed The printer default colors are fixed
172. T to trace the program as it runs Press ALT R S on the computer to run the program 4 When the program pauses the analyzer is in remote mode You can verify this by observing the lights in the INSTRUMENT STATE area of the analyzer The R remote and L listen lights should be on Try pressing any key on the analyzer except LOCAL Nothing happens The source is also in remote mode Now press LOCAL and verify that the keys on the analyzer are active Also notice the R light went out when you pressed LOCAL The source went into local mode along with the analyzer 5 Press ENTER on the computer The analyzer is again in remote mode This time however the LOCAL key is locked out Try pressing LOCAL and the other keys None of the keys on the analyzer or the source cause any action 6 Press ENTER on the computer All instruments on the HP IB interface are returned to local mode including the analyzer and source Verify that the R light on the analyzer is off and the REM light on the source is off 7 Press ENTER on the computer The analyzer and source are both preset Note that the computer sent the instrument PRESET command only to the analyzer The analyzer in turn preset the source Remember to preset both the analyzer and the source you only need to send the instrument PRESET command to the analyzer Do not send instrument PRESET to the source by way of passthru mode discussed in program 3
173. TPUT Sna IP BL5 PT15 60 GINIT 70 PLOTTER 15 717 HPGL 80 WINDOW 0 2924 0 2047 90 CLIP 0 2900 0 2000 100 OUTPUT Passthru EP GP1 1 DF 110 PEN 9 120 GRID 100 100 130 PEN 10 140 RESTORE Graphix 150 REPEAT 160 READ Pen mode X Y 170 SELECT Pen mode 180 CASE D 190 DRAW X Y 200 CASE M 210 MOVE X Y 220 END SELECT 230 UNTIL Pen mode E 240 MOVE 600 1600 250 OUTPUT Passthru USING SI0 28 0 34 LBCONNECTION DIAGRAM CHR 3 260 MOVE 1200 250 270 LABEL DUT 280 Graphix 290 M 300 800 D 1100 800 D 1100 1100 D 300 1100 DATA D 300 800 7M 800 800 D 800 1100 310 DATA M 1500 800 2300 800 2 2300 1200 D 1500 1200 320 DATA D 1500 800 M 1950 800 1950 1200 330 DATA M 875 850 D 875 500 D 1200 500 340 M 1400 500 D 2050 500 D 2050 850 350 M 1200 400 D 1400 500 D 1200 600 D 1200 400 360 E 0 0 370 END Program 9 explanation Line10 Assign an I O path to the address of the analyzer Line 20 Assign an I O path to the passthru address of the analyzer Line30 Abort any transfers and clear the HP IB interface of the computer Line 40 Clear the HP IB interface of the analyzer Line50 Preset the analyzer and blank the CRT display Define the CRT graphics as the target of passthru commands The graphics address is always one less than the analyzer s HP IB address Line 60
174. URN IQQUTSP CALL IOQ0UTPUTSCPassthru amp AS LENCA 2 IF PCIB ERR NOERR THEN ERROR PCIB BASERR RETURN Program 3 explanation Line10 Call the QuickBASIC initialization file OBSETUP Line20 Clear the computer CRT Line 30 Assign the interface select code to a variable Line40 Assign the address of the analyzer to a variable This is the analyzer s control address Line50 Assign the analyzer s passthru address to a variable By communicating to this HP IB address the computer will control a device connected to the 8757 SYSTEM INTERFACE Line60 Define a system timeout of 10 seconds Perform error trapping Line 70 Abort any HP IB transfers Perform error trapping Line 80 Clear the HP IB interface of the analyzer Perform error trapping Line90 Preset the analyzer and source Linel00 Tell the analyzer which device is controlled through the analyzer s passthru address In this case the source device 19 Line 110 Send a command to the source Command it to output its current start frequency Line 120 Read the start frequency from the source Perform error trapping Line 130 Scale the start frequency to display it in GHz Line 140 Command the source to output its current stop frequency Line 150 Read the stop frequency from the source Perform error trapping Line 160 Scale the stop frequency to display it in GHz Line 170 Exit passthru mode by addressing the analyzer Line 180 Printthe start and stop fre
175. Use this softkey to turn it on STORE OPEN measures the open circuit response Connect the open circuit to the bridge or detector test port and press STORE OPEN The message SHORT UPEN CAL SAVED IN CH1 MEM appears on the CRT The channel indicated depends on which channel is active The open and short calibration data has been averaged and is stored in the active channel memory The first calibration menu is automatically presented Now the message For NormalizedMeas select DISPLAYIJ MEAS MEM appears on the CRT if you were not already in MEAS MEM mode Press these keys to normalize the measurement THRU prompts you through a thru calibration This calibration is automatically stored in memory in dB dBm format When the THRU softkey is pressed the prompt CONNECT THRU STORE WHEN READY appears on the CRT and a second menu layer is presented AVERAGE ON OFF toggles averaging on and off This is the same averaging function that is engaged by pressing AVG ON OFF in the averaging menu If you had previously turned averaging on it will automatically be toggled off when THRU is pressed Pressing AVERAGE ON OFF toggles averaging ononly for the measurement of the thru The averaging factor does not change from the last value set in the averaging menu You must return to the averaging menu if you wish to change the averaging factor STORE THRU measures the thru response Connect the thru between the two points between which
176. VE Accesses storage menu SET UP DISK Accesses disk menu INIT DISK Sets up initialization INIT YES Starts initialization Save Recall functions The user may store parts or all of the information currently displayed on an external disk The SAVE and RECALL hardkeys offer a number of choices for saving or retrieving data as shown in the following menus SAVE 8757C A P t To store information on an external disk each file must have a title with 8 characters or less The TITLE FILE softkey is located in the SAVE and RECALL menus and uses the same title space as measurement titles When selected the name of the last file stored will be displayed in the title area Following preset the file title defaults to FILET When the file name has been entered selecting STORE TO DISK allows the user to store all or part of the information currently displayed Once stored the information may be recalled at any time by selecting RECALL and LOAD FR DISK If a title identifying the measurement was present prior to selecting the file name when the file is recalled from the disk the measurement title will reappear in the title area If a different file is required the FILE DIRECT softkey dis plays a directory of all the files that have been stored on that particular disk The HP 8757C displays the contents of each file by creating sub files for the instrument state trace data trace memory and CRT g
177. Wear a grounded wrist strap Use an anti static mat e Discharge static electricity from your body and from all devices before making connections or cleaning connectors Protection against electrostatic discharge is essential before cleaning or inspecting connectors attached to any static sensitive circuits such as those found in bridges and detectors or to test ports which may be connected to similar circuits Static electricity builds up on the body and can easily damage sensitive internal circuit elements when discharged by contact with the center conductor Static discharges too small to be felt can nev ertheless cause permanent damage Devices such as calibration components and devices under test can also carry an electrostatic charge Always install a grounded anti static mat in front of the test equipment and wear the grounded wrist strap attached to it Such a mat including installation hardware and a grounded wrist strap is avail able as HP Part Number 85043 80013 In addition before cleaning inspecting or making any connection to a static sensitive device or test port ground yourself for example by grasping the grounded outer shell of the test port briefly as shown in Figure 2 Also discharge static electricity from all devices before connecting them by touching the device briefly to the outer shell of the test port or to another exposed ground This wili discharge any static elec tricity on your body or the device a
178. While this isn t necessary for our connection diagram it does give you a good indication of where the X and Y coordinates are on the analyzer s CRT 4 The labeling is added The labels CONNECTION DIAGRAM and DUT are done using the analyzer CRT s internal character set 5 Allofthelines are plotted on the analyzer s CRT If brighter lines are desired draw each line twice or select a different pen number In this example only graphics page 1 is used You can inde pendently control up to 7 separate pages of graphics information If you write too much information onto one page it overflows onto the next page When a graphics page is selected the first location of mem ory that receives information identified by the pointer is reset to the beginning of the page Thus as information is written onto the page the old information is destroyed If we were plotting a line this would appear as a new trace overwriting an old one 19 Program 10 learning the instrument state Being able to save a specific instrument state is helpful when it is needed several times in a test or measurement procedure You can save the instrument state by manually logging the important analyzer and source parameters such as start stop frequency sweep time number of trace points scale per division and display format then replace them at the appro priate time A simpler approach is to save the instrument state in one of the nine
179. a on the CRT Detector offsets are valid during calibration as well as during measurement Detector offsets remain in effect until they are changed Power on and off or preset will not change an offset Offsets affect a detector input not a detector The offset always applies to a measurement made on that input regardless of which channel selects the measurement or if a register is recalled PRIOR MENU returns the previous menu 24 Operating Reference 8757 EXT DET CAL appears only if an HP 85025C Detector Adapter is connected to the analyzer Use this function to calibrate the analyzer to a detector connected to the detector adapter Pressing this softkey presents another menu layer DET PWR CAL is a calibration sequence that consists of providing the analyzer with two known power levels Once you perform a calibration with a detector the analyzer identifies that detector by its calibration value CAL VALUE You can use the detector and enter its calibration value on any analyzer input See the HP 85025C Detector Adapter Operating and Service Manual for instructions on this procedure It is written to apply to the HP 8757A but is also compatible with the HP 8757C E PRIOR MENU returns you to the previous menu AUTOCAL ON OFF gives you control over the automatic regeneration of the internal calibration tables for the detector inputs Pressing this softkey toggles autocalibration on and off See 8757C E Se
180. ace display Out of band rejection 24 14 13 Output power gain measurements 15 Output results P Peak to peak ripple PLOT PLOT CUSTOM Preset PRINT PRINT GRAPH R RECALL REF REF LEVEL REF POSN Reflection measurements Return Loss 10 13 10 10 10 10 9 22 12 12 17 18 S SAVE SCALE SCALE TO P1P2 Signal separation Smoothing SPCL Status notations Storing information Externally Internally SWR Mode T Termination device Transmission measurements TRC EMT SWR dB U U uncalibrated W Windows smoothing measurements 17 11 13 14 CONVERTING EXISTING HP 8757A SOFTWARE TO THE HP 8757C E Programs written for the HP 8757A with firmware revision 2 0 or higher should require minimal or no changes to work on the HP 8757C E The majority of the differences are invoived with the graphics commands These commands are documented in the introductory programming guides and the quick reference guide However to assistin upgrading existing software review the following list when using programs written for the HP 8757A Display Graphics HP GL Commands 1 The DEFAULT command DF sets default values This command is equivalent to DI 1 0 SI 0 14 0 17 and places the HP 8757C in monochrome mode as opposed to color 2 The LINE TYPE command LTy z is no longer available on the HP 8757C E 3 The OUTPUT P1 and P2 POSITION command O
181. ailable Option 001 Fourth Detector input i i i i i i i 1 i i i H j 1 i i i i H t i i i i i t m 9 3i 1 ID 2 V i i i i 1 i i i i j i H H i E 1 7 i i i i i i The Option 001 is supplied with four front panel detector inputs A B C and Option 602 HP IB Disk Drive The Option 802 adds one HP 91220 3 5 inch Dual Disk Drive and one HP 10833A 1 m 3 3 f HP IG cabie HP 8757C E General Information 1 5 1 6 Option W30 Extended Service Option W30 adds two additional years of return to Hewlett Packard hardware support following the first year of warranty Option W30 can be ordered at the time of sale only Instruments ordered with Option W30 are identified on the serial number plate Option 0D2 Factory Refurbished Demonstration Instrument Option 002 instruments designated by a yellow option tag on the serial number label are instruments that have been used as demonstration units for less than 12 months then returned to the factory for electrical and mechanical refurbishment The standard warranty and specifications apply Option 908 Rack Mount Without Handles The Option 908 analyzer is supplied with a rack mount kit containing a pair of flanges and the necessary hardware to mount the analyzer with handles detached in an equipment rack with 482 6 mm 19 in horizontal spacing Sec
182. ain purposes with SMA and precision 3 5mm connectors to connect a device with one connector interface to a device or to test equipment that has another interface or to reduce wear on connectors that may be difficult or expensive to replace Reducing wear is possibly the most important use of adapters especially when devices that have SMA connectors are being used in most applications two adapters will be required one each at the input and the output of the device Male female adapters cause no change in the sex of the interface The same interface is presented when the adapter is in place as is presented in the original setup Same sex adapters male male female female change the sex of the interface For example if the original interface presents a male connector attaching a female female adapter will result in a female interface to which devices or cables that have male SMA or male precision 3 5mm connectors can be connected 3 5mm to 3 5mm or SMA Adapters High quality precision adapters sometimes called nector savers are recommended whenever more than a few connections will be made between SMA and precision 3 5mm connectors In this way only the adapter needs to be replaced when it is worn and the precision connector is at all times protected from accidental damage due to the SMA connector Figure 25 shows the 3 5mm to 3 5mm adapters that are available for making through or connector saver connections betwee
183. alyzer measurement system can be calibrated over several different frequency ranges and changed from one to another very quickly with out recalibration If you wish to transfer a higher resolution trace with the HP 8757C modify line 110 to be IP SP801 for 801 points Then modify 401 in lines 50 and 60 to 801 Program 7 using the TAKE SWEEP command To make measurements as quickly and efficiently as possible itis often necessary to synchronize the source with the ana lyzer The TAKE SWEEP command gives the analyzer the ability to command the source to make a specified number of complete sweeps 1 to 255 This command is especially useful when using the trace transfer method of reading data from the analyzer To use the TAKE SWEEP command place the analyzer in non swept mode SW0 Then give the TAKE SWEEP com mand with the number of sweeps desired TSd At the end of the specified number of sweeps the analyzer informs the computer of the completion of this operation by setting a bit in its status byte The computer can detect this event in two ways Monitor the status byte continuously until the bit is set polling o Let the analyzer generate a service request SRQ and interrupt the computer Table 1 is a diagram of the status bytes of the analyzer It shows all of the bits that can be used to either monitor or interrupt the computer In this program bit 4 decimal value 16 is used to signal operation com
184. am other start and stop frequencies by following the example in program 3 Line 250 On the computer CRT print the value and actual frequency of the cursor Line 260 End program execution Running program 4 1 Clearthe program memory of the computer and type in the program 2 Press RUN on the computer 3 Thecomputer turns on both channels and sets channel 1 to reflection input A and channel 2 to transmission input B The cursor is positioned to the maximum point on the channel 2 trace and its value and position are read and displayed At preset the number of points per trace is 401 4 The computer displays the prompt Desiredcursorposition 0 4000 Type in a number between 0 and 400 and press Continue A position of 0 represents the left side of the analyzer s CRT lowest frequency and 400 represents the right side of the CRT highest frequency The position is set and the cursor s value and position are read and printed on the CRT of the computer 5 The computer stops and displays the prompt Cursor frequency GHz Enter a frequency within the current start and stop frequencies of the measurement 0 01 to 20 GHz The nearest cursor position is calculated and set The cursor s value and position are read and the actual cursor frequency is calculated from the cursor s position Note The original desired frequency and the actual cursor frequency are usually different Because there are only 401 possible curs
185. analyzer Perform error trapping Return from the subroutine Running program 10 1 Clear the computer CRT and type in the program 2 Press ALT R IS on the computer 3 When the computer stops and displays SET UP SYSTEM PRESS CONTINUE Adjust the analyzer and source to a preferred instrument state then press the ENTER key on the computer 4 Thecomputer will save the learn strings of both the analyzer and the source After completing this the analyzer and source will be preset to destroy your original instrument state 5 The computer stops and displays TO RESTORE SETUP PRESS CONTINUE Press the ENTER key The computer will restore your original instrument state via the two learn strings Verify on the displays of the analyzer and the source that your state has been restored This example is designed to work with the HP 8350B Sweep Oscillator which has a learn string of 90 bytes The program can be easily modified to work with the HP 8340B and 8341B Synthesized Sweepers which have learn strings 123 bytes in length To do this change line 40 to be 40 Maxswpr 123 To work with the HP 8360 Series Synthesized Sweeper the modifications are more extensive due to its variable length learn string To do this change and or add the following lines 40 Maxswpr 700 212 Lswpr0 SPACESC3 214 CALL IOENTERS Passthru amp Lswpr0 3 Actual IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Maxswpr
186. and via an interrupt is more time efficent than the polling method previously used because the computer can be doing something else during the 10 sweeps To use the sweep hold mode modify line 140 to SW2 instead of SW0 CS RM16 and delete lines 150 170 180 and 190 The program will wait at line 200 until the 10 sweeps are completed Whenever practical use the service request interrupt to sense the end of a TAKE SWEEP command In fact you can use the time to do plotting or printing of data instead of sitting in a loop Service requests are useful for other events as demonstrated by the next program 15 16 Table 1 8757C E Status Byte Descriptions STATUS BYTE 1 Decimal i N A Request SRQ on SRQ on SRQ on SRQ on SRQ on SRQ on Any Service HP IB Operation Softkey Change in Numeric Front Panel Function SRQ Syntax Error Complete Only Extended Entry Key Pressed Sweep Plot Pressed Status Byte Completed or Print HP IB Front Panel EXTENDED STATUS BYTE 2 Decimal Value N A SRQ on SRQ on SRQ on SRQ on Function Detector Front Panel Limit Test Action Knob Self Test Uncal Preset or Failed Requested Activity Failure Power on not possible Program 8 programming the softkeys The HP 8757C E has eight screen labeled softkeys that 200 Wait srq make your measurements
187. ange you defined NOTE You must address the analyzer after using passthru mode to return it to normal swept operation Any command can be sent via passthru mode to any instrument on the 8757 SYSTEM INTERFACE and any data can be read Service requests and parallel polis do not pass through the analyzer Program 4 cursor operations To enhance the speed and accuracy of measurements the analyzer contains a built in cursor that displays the fre quency and magnitude of a trace at any given point To make measurements even more efficient the cursor may be set to the maximum or minimum point on the trace simply by pressing a softkey These cursor functions are available via HP IB commands With a computer the cursor may be turned on and off its position 0 to n 1 where n is the number of points per trace set its value and position read and set to the maximum or minimum point on the trace The cursor functions all apply to the active channel the channel accessed most recently You have complete control over cursor operations via HP IB Cursor programming is especially useful for measuring parameters like flatness and maximum power where you are interested in the highest and lowest point on the trace For measuring parameters such as 3 dB points and other specific points not a maximum or minimum it is more efficient to use either the cursor search functions available on the HP 8757C only or to read the entire trace and search for
188. ar the end of the handle every time and always in the same orientation When possible begin tightening the connection with the wrench held nearly horizontal Making Connections Use a torque wrench to make the final connection INTERNAL PIVOT KNURLED END POINT OF WRENCH OF HANDLE Hold the wrench lightly by the knurled end of the handle only to the plane of the outer conductors Allow the wrench to transmit force to the connection through its internal pivot point Do not twist the wrench Proper torque has been achieved when the break point of the wrench is reached Do not overtighten Figure 12 Using the Torque Wrench 1 of 2 i Apply force on one side of the wrench only perpendicular to the wrench and parallel Making Connections 27 28 Avoid holding the torque wrench incorrectly NOT RECOMMENDED Wrench gripped tightly iens ay Pu m m pa e m Jg 1 5 lt o a Q 3 c 3 5 Always use the wrench the correct orientation RECOMMENDED Eo y Ag IT Wu NOT RECOMMENDED SAY SM i uo RA dum teats su DIE Figure 12 Using the Torque Wrench 2 of 2 Making Connections Table 2 Torque Wrenches Connector HP Part Precision 7mm 12 b in 1250 1874 136 N cm Precision 8 Ib in i 1250 1863 3 5mm 90 N cm Type N NOT REQUIRED Ty
189. ate When preset the analyzer defaults to the conditions shown below The instrument preset function operates the same as the front panel PRESET key on the analyzer and the source When presetting the analyzer and source send the PRESET com mand only to the analyzer The analyzer will preset the source attached to the 8757 SYSTEM INTERFACE HP 8757C E instrument preset conditions Channels 1 and 2 on The channel menu appears in the softkey label area of the CRT Measure power A on channel 1 Measure power B on channe 2 Measure power C or B on channel 3 Measure power on channel 4 Display measurement data in log magnitude format Scale 20 dB div Reference level 0 dB for all channels Reference level step size 20 dB Averaging off Averaging factor 8 Cursor off Ail labels on Channel 1 as the active channel Modulation drive on Number of points 401 Detector mode set for AC detection Smoothing set for 5 096 of span off Cursor format log magnitude Search value 3 dB Adaptive normalization off Temperature compensation on Repeat autozero off e o 9 9 o0 9 a e e Source e Instrument preset Sweep time set to 200 ms HP 8350B square wave modulation on 8340 41 SHIFT PULSE RF Output on Plotter e Abort plot ifin progress e Pland P2 scaling points unchanged Selection of plotter pens unchanged Printer e
190. ation Line 10 Line 20 Line 30 Line 40 Line 50 Line 60 Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Line 130 Line 140 Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Direct the printed output to the computer CRT Assign an I O path to the address of the analyzer Assign an I O path to the passthru address of the analyzer Abort any transfers and clear the HP IB interface of the computer Clear the HP IB interface of the analyzer Preset the analyzer and source Tell the analyzer which instrument is controlled through the passthru address 19 is the source Put the analyzer in non swept mode This step is necessary when you read single values After receiving this command the analyzer stops updating its display Define a start frequency for further measurements in GHz Define a frequency increment in GHz Put the source into CW mode at the start fre quency and set its frequency step size to that of the frequency increment Command the analyzer to measure reflection input A on channel 1 This statement also causes the analyzer to exit passthru mode Make 21 measurements at equally spaced CW frequencies Command the analyzer to send the current reading of channel 1 the active channel to the computer The reading is taken immediately Read the value In this instance no format has been defined so the default format of ASCH is in effect Print the mea
191. ations tables under any of the following conditions AUTOCAL ON or AUTOCAL OFF Atinstrument preset power on or recall instrument state e CONFIG SYSTEM softkey selected Only if AUTOCAL ON e Detector or bridge configuration changed Large temperature change Ata fixed 5 minute interval HP 8757C E Operating Reference 25 To regenerate the calibration tables the analyzer determines the following for each detector input Detector or bridge type AC only or AC DC e Detector or bridge power versus voltage characteristics Temperature of the detector AC DC accessories only and the log amplifier Using these readings the analyzer automatically computes the internal calibration tables Depending on the configuration this table regeneration process can last a few seconds When completed the message CONF 1G SYSTEM COMPLETED appears on the CRT If the analyzer is in a thermally stable environment temperature drift less than 5 C thermal drift in the log amplifiers is minimal The detectors however may be exposed to significant changes in tem perature AUTOCAL ON automatically compensates for significant temperature changes TEMPERATURE COMPENSATION With TEMPCMP ON continuous temperature compensation to the data is performed This corrects the measurement data for small drifts in temperature without the need to recompute the calibration tables Always use temperature compensation when makin
192. be com pared to absolute input or output power Set up channel 2 accordingly 15 Preset Connection Utilize the insertion loss measurement configuration Add attenuation where appropriate Controls Setup the measurement Measurement CHANNEL 1 Activates channel 1 MEAS B R Sets up channel 1 for gain measurement CHANNEL 2 Activates channel 2 MEAS B Sets up absolute output power measurement on channel 2 CHANNEL 1 Accesses channel menu CHANNEL 4 Activates channel 4 MEAS R Sets up absolute input power measurement Source parameters SHIFT CW Sets up display for gain and power versus input power at one frequency set to desired frequency in amplifier range POWER LEVEL Set start power POWER SWEEP Enter the sweep range required to saturate the amp e g 10 dB per sweep In the SHIFT CW mode the source s SWEEP OUT drives the horizontal axis of the HP 8757C E display to make this axis power instead of frequency Calibrate The measurement will require a thru calibration on channel 1 for each CW test frequency when the HP 8757E is utilized Whereas the HP 8757C will require a thru calibration chan nel 1 only once for the full range of the amplifier under test then the adaptive normalization function may be utilized to adjust the calibration data to the selected CW frequency The thru calibration required is described in the insertion loss and gain measurement setup section On the HP 8757
193. bel color Perform system configuration of detectors and channels Color list black Color list green Color list blue Color list red Color list salmon Color list white Color list yellow Cursor to minimum Brightness adjust one color Color adjust one color 2 HP 8757C Option 001 detector C 3 Limit line functions valid only for channels 1 or 2 HP 8757C only 22 Tint adjust one color C R ratio measurement Clear status bytes Auto system calibration on off Cursor on off CW mode on off Cursor to maximum Detector A offset set tod Detector B offset set tod Detector C offset set to d Set default colors Set disk format to ASCII Set disk format to binary Display Hold on off of the active channel trace Set disk HP IB address Set disk unit number Set disk volume number Delete file from disk Allinputs setto DC detection Allinputs set to AC detection Step down decrement Detector R offset set tod Display trace data in log magnitude Display trace data in standing wave ratio SWR format Erase all save recall registers Start frequency label Stop frequency label Format data ASCH Format data binary HP BASIC compatible Format data extended ASCH Format data binary PC compatible Logarithmic dB cursor format SWR cursor format Step sweep on off Input A absolute power measurement Input B absolute power measurement Input C absolute power measurement In
194. bration standard it is impossi ble to completely eliminate the repeatable measurement systematic errors Instead these errors are minimized through a calibration process called normalization where the DUT is measured relative to the magnitude response of a known standard MEAS MEM Common systematic errors are Frequency response Removable Directivity 6 Ggaieandioadgnat a Limited by quality of test setup The accuracy of the calibration is dependent on the quality of the standards used for calibrating Since calibration stan dards are very precise excellent accuracy enhancement is acheived Unless the Adaptive Normalization function is used HP 8757C only key measurement parameters such as the frequency may not be changed following calibration Power may be changed if the system is configured for ratio measurements When new parameters are required the previous calibration becomes invalid and recalibration must occur For testing one or more devices each calibration sequence may be saved in separate storage registers When the source is connected to the 8757 System Interface the front panel states of both the analyzer and the source are saved Transmission measurement calibration For a transmission measurement a thru is the calibration standard It is accomplished by removing the DUT and directly connecting the measurement test port to the detec tor thus establishing a 0 dB loss or gain reference Calibrati
195. bus and sending the SERIAL POLL DISABLE SPD com mand The SRQ is cleared only by executing either a serial poll device clear DCL selective device clear SDC PRE SET or sending the CS or OS commands The request mask function RMd is used to specify a particu lar set of conditions for initiating a service request SRQ The mask value is determined by summing the decimal values of each selected function or condition that is desired If a bit in the request mask is set to zero that bitin the status byte will be masked and an SRQ cannot be initiated For example the command RM41 indicates an SRQ can be initiated by the functions of bits 0 3 and 5 The default value of the request mask at power on is 00000000 or 0 decimal no SRQ s are ini tiated Status byte The HP 8757C E responds to a serial poll by sending the sta tus byte 1 Both the status byte 1 and the extended status byte 2 are obtained by sending the OUTPUT STATUS OS command and by immediately reading both byte values respectively The status bytes of the analyzer are described in table 6 When bit 6 request service of the status byte 1 is true one an SRQ has occurred See Service Request for the conditions causing a service request Bit number 2 of the sta tus byte 1 indicates whether a change has occurred in the extended status byte 2 If bit number 2 is true then the extended status byte 2 should be accessed via the OUTPUT ST
196. c storage medium Display 1 To show annotation and measurement data on the CRT 2 The CRT and its associated driver circuits A15 Engage To activate a function Enter The process of inputting information to the analyzer Firmware Programs or instructions that are stored in read only memory EPROM GSP An abbreviation for Graphics System Processor A14U25 The central controller for all display processing Graticule An electronically drawn grid on the CRT Hardkey A front panel key which engages a single analyzer function or presents a single menu of softkeys Hex An abbreviation for hexadecimal number system base 16 Horizontal Resolution How closely spaced the horizontal data points are taken over the full sweep HP iB An abbreviation for Hewlett Packard Interface Bus HP IB is Hewlett Packard s hardware software documentation and support for IEEE 488 and IEC 625 worldwide standards for interfacing instruments Hue 1 The dimension of color that is referred to a scale of perceptions ranging from red through yellow green and blue and back to red 2 A particular gradation of color tint shade Initialize The process in which information locations are assigned to a disk to prepare the magnetic media to accept files Insertion loss The difference between the power measured before and after the insertion of a device 8757 Glossary Intensity Brightness Emitting or reflecting light Lumino
197. ce HP 8757C E The source instrument state is still completely stored to disk when the frequency labels are turned off However when the instrument state is loaded from disk the frequency labels will be turned off and the source frequency readout blanked as they were when the instrument state was stored HP IB programming commands also allow you to turn the frequency labels off and operate in the secure frequency mode See Secure Frequency in any of the Remote Operation documents TITLE OFF toggles the titles on and off without erasing the title START LABEL is used to specify the start value of the left graticule This function can only be engaged with the system interface off After pressing this softkey enter the start frequency with the numeric keypad and terminate the entry with the appropriate units softkey such as GHz or MHz Termination of the entry presents the labels menu STOP LABEL is used to specify the stop value of the right graticule This function can only be engaged with the system interface off This function is engaged the same way as START LABEL PRIOR MENU returns the system menu MODE AC DC toggles between AC and DC detection modes If a compatible source is connected to the system interface the source modulation is controlled automatically normally on for AC and off for DC This function also controls the MOD ON OFF function When AC is engaged the analyzer modulatio
198. ce the measurement is not subject to variations in source modulation Also DC mode is more easily referenced to a power meter in AC mode the power meter reading would be nominally 3 dB lower than the scalar analyzer reading due to the square wave modulation of the source 25 AC DC detection Active channel Active devices Active entry area Adaptive normalization ADJUST DISPLAY Alternate sweep Aperture AUTOSCALE AUX mode Averaging B Bandwidth 3 dB Basic system configuration C CAL Calibration Reflection Transmission Color selection CLEAR SAV RCL CRT Display CURSOR CW mode source D Data entry Default colors Default conditions DEFINE CUSTOM Device termination Disk setup DISPLAY Display CRT Dynamic range optimizing E ENT External storage Frequency Blanking Front panel Function keys G Gain compression General measurement sequence GRAPH COLOR GRAPH MONO 26 25 15 15 24 21 14 14 14 15 10 10 1 Initializing a blank disk Insertion loss Instrument state keys Internal storage L Labels Limit lines Flat segments Point segments Sloped segments M Markers source MAX MEAS MEAS MEM Measurement accuracy Measurement sequence Measurements reflection Measurements transmission Measuring the device MIN Mode labels MODIFY COLOR Monochrome mode HP 8757C N Noise reduction Optimizing tr
199. cillator Programming Note Quick Reference Guide for the HP 8340B Synthesized Sweeper o HP 8360 Operating and Programming Reference HP Vectra Personal Computer literature HP 82335A HP IB Command Library Manual e Microsoft QuickBASIC BASIC Language Reference Manual Microsoft QuickBASIC Learning and Using Microsoft QuickBASIC e Microsoft QuickBASIC Programming in BASIC Selected Topics Equipment required 1 HP8757C EScalar Network Analyzer 1 HP 8350B Sweep Oscillator with plug in or HP 8340B 41B Synthesized Sweeper or HP 8360 series Synthesized Sweeper 1 HP Vectra Personal Computer or compatible with Microsoft QuickBASIC 4 5 HP 82335A HP IB Interface Card MS DOS 3 3 or higher and at least 320K bytes of memory 1 HP85027A B C D E Directional Bridge 1 HP11664A E Detector or HP 85025A B D E Detector with connector type to match bridge and test device 1 Shielded open circuit with connector to mate with bridge 1 Short circuit with connector to mate with bridge 3 HP11170C BNC cables 122 cm 48 in 4 are needed with HP 8340B 41B 2 HP10833A B C D HP IB cables 1 Testdevice Set up Connect the instruments as shown in figure 1 The following procedure sets the HP IB addresses of the instruments to operate properly with the programs in this guide If the HP 82335A HP IB interface card is not installed in the HP Vectra PC follow the instructions in the HP 82335A HP IB Command Library Manua
200. cing metal in the same way as a plow moves dirt Deep scratches running concentrically as do the grooves in a phonograph record generally indicate that one or both of the connector mating plane surfaces was not perfectly clean when the connection was made or that the one of the connectors has a burr or high spot somewhere on its surface Deep scratches running across the mating plane surface are generally the result of rough handling during connection disconnection or storage On gold plated connectors any scratch that goes through the gold plating to the beryllium copper underneath is a possible source of trouble Inspect the scratch carefully under magnification to see whether the scratch has left a high spot of pushed up meta on the mating plane surface If it has do not use the connector It will only damage other connectors it is mated to by cutting into the plating If all of the metal displaced in the scratch has been removed or has worn away and no high spots remain the connector may still be usable Full flat circular contact between the mating plane surfaces will not occur but the connection may still be satisfactory for most purposes Dents Dents occur most often on the outside edges of mating plane surfaces and under magnification they look like small craters or valleys Metal is pushed outward and upward from the point of impact Sometimes dents are caused by careless handling or assembly of connectors during manufacture
201. cision 7mm Connectors Gaging Precision 7mm Connectors Gaging is discussed in detail in Part One of this Microwave Connector Care Manual which should be consulted for further information The critical mechanical specification in precision 7mm connectors is the recession setback of the center conductor relative to the outer conductor mating plane with the center conductor collet removed No protrusion of the center conductor in front of the outer conductor mating plane is ever allowable and sometimes a minimum recession is required Gaging precision 7mm connectors Figure 15 is done with the aligning pin removed from the gage plunger and using the flat end of the gage calibration block except when the connectors have no support beads as in the case of beadless airlines In these cases the removable aligning pin is installed into the gage plunger and is used to center the gage and center conductor within the connec tor When the aligning pin is used the recessed end of the gage calibration block is used Before gaging the connector always extend the sleeve of the connector fully This creates a cylinder into which the gage can fit and greatly reduces the danger of damage to the connector due to the gage slipping sideways during gaging If the connector is within specification re insert the collet or insert a new one and gage the connector again with the center conductor collet in place This is necessary to verify that the connector i
202. color selections For example CLB sets the background to black Note Select the feature to be changed before selecting the color Define custom colors with COT COB and COC These commands are used like the color list commands For example CGN COB100 COC75 COT100 defines all three parameters of a feature s color Set grid color Set warning label color Selects a color from the color list for the feature previously selected x represents colors from the color list Valid values for x are W White Y Yellow S Salmon B Black L Blue R Red G Green Custom color brightness affects the feature last selected d ranges from 0 to 100 Custom color adjust affects the feature last selected d ranges from 0 to 100 Custom tint adjust affects the feature last selected d ranges from 0 to 100 1 HP 8757C oniy 2 Revision 3 1 or above for an HP 8757C revision 4 1 or above for an HP 8757E 12 Tablel Function Select Commands 6 of 6 HP IB Disk The data sent after this command is stored in ASCII format This is Save Recall important forretrieving the data for usein another program The data sent after this command is stored in fast binary format allowing quicker file access times Sets the HP IB address for the disk drive on the bus The valid range for d is 0 to 29 Selects active disk unit For example With an HP 9122 select unit 0 or unit 1 The valid range ford isO to 15 For
203. connected to the 8757 system interface All functions are turned off then the following instrument states are set ANALYZER The channel menu appears in the softkey label area of the CRT amp amp 9 9 9 9 o 9 9 9 6 6 6 9 se Measure power A on channel 1 on Measure power B on channel 2 on Measure power C or B on channel off Measure power R on channel 4 off Display measurement data in log magnitude format Scale 20 dB div Reference level 0 dBm for all channels Reference level step size 20 dB Averaging off Averaging factor 8 Cursor off All labels on Channel menu on Channel 1 as the active channel Modulation drive on Number of trace points 401 _ Detector mode set for AC detection smoothing aperture set for 5 0 of span off Cursor format log magnitude Search value 3 dB Adaptive normalization off Temperature compensation on Repeat autozero off 1 HP 8757C only Operating Reference HP 8757C E SOURCE instrument preset Sweep time 200 ms HP 8350B square wave modulation on HP 8340 8341 SHIFT PULSE on RF output on PLOTTER Abort plot if in progress P1 and P2 scaling points unchanged Selection of plotter pens unchanged PRINTER Abort plot or print if in progress DISK DRIVE Aborts any data transfer in progress Unit number unchanged Volume number unchanged ASCII or binary mode unchan
204. connection Extending the sieeve creates a cylinder into which the other connector fits Spin the knurled connector nut to make sure that the threads are fully extended Seating Precision 7mm Connectors n applications requiring the utmost in repeatability and accuracy one additional step has been found to be helpful in making connections between precision 7mm connectors it is called seating and is recommended only for the most demanding measurement applications and only for gold plated precision 7mm connectors After the preliminary connection has been made using very light finger pressure 2 inch ounces of torque hold the connector nut stationary with one hand and with the other hand gently turn the body of the device being connected 5 to 15 degrees in a direction opposite to the direction of tightening A few degrees is enough on a clock face one hourly division is 30 degrees twice the maximum amount of rotation recommended for seating Smooth uniform movement without resistance should occur almost immediately Often a sudden slight breaking loose of the connection is felt when the device being connected is rotated This is not abnormal and occurs as the mating plane surfaces or connector nut threads move into correct alignment it results in a slight loosening of the connector nut however Therefore if it occurs tighten the connector nut slightly and repeat the rotation Smooth uniform motion without resistance should now occur Make
205. connector type are included in many Hewlett Packard calibration kits and they are also available separately Torque settings and part numbers appear in Table 2 in using a torque wrench prevent rotation of anything other than the connector nut that is being tightened with the torque wrench Generally this is easy to do by hand all the more so if one of the connectors is fixed as on a test port in other situations an open end wrench can be used to keep the bodies of the connectors from turning Hold the torque wrench lightly by the knurled end of the handle only in the manner shown in Figure 12 Apply force at the end of the torque wrench only perpendicular to the wrench and always in a plane parallel to the outer conductor mating planes This will resuit in torque being applied to the connection through the wrench until the break point of the wrench is reached Avoid pivoting the wrench handle on the thumb or other fingers This results in an unknown amount of torque being applied to the connection when the break point of the wrench is reached Avoid twisting the head of the wrench relative to the outer conductor mating plane This results in applying more than the recommended torque Above all avoid holding the wrench tightly in such a way that the handle is not pivoted but simply pushed downward the same amount throughout its length If this is done an unlimited amount of torque can be applied Hold the wrench at the same point ne
206. ction Four two in the HP 8757E independent display channels process signals from the HP 85025 85026 or 11664 Detectors and the HP 85020 27 Bridges The data is logarithmically displayed in single input or ratio mode with respect to frequency on the internal CRT Three detector inputs A B and R accept AC or DC detected signals from detectors or bridges The Option 001 has four detector inputs A B C and Modulator Drive The modulator drive output of the analyzer provides the circuitry to drive the HP 8340 and 8341 Synthesized Sweepers and the HP 11665B Modulator Modulator drive may be turned on and off via the front panel or HP IB In the OFF state the modulator drive signal turns the HP 116658 fully on for minimum insertion loss Frequency 27 778 kHz 12 Hz Symmetry 50 1 Dynamic Range Dynamic Power Accuracy Absolute Power Accuracy These are system specifications and depend on the detector being used The following examples show frequently used Hewlett Packard detectors Dynamic Range Detector Dynamic Range HP 11664A E AC mode 16 to 60 dBm HP 85025 series AC mode 16 to 55 dBm DC mode 16 to 50 dBm Bynamic Power Accuracy 50 MHz 25 5 C 0 dBm reference ume I EXE p PEE qu 9 io baa eZ oe eee a ee Ne eg CG a A dS era i EE AR RAE 420 10 0 40 20 30 40 50 60 Change in power dB Note For lt 20 dB change of power
207. ctioning properly Lack of any signal displayed when using the modulator drive output from the analyzer could indicate a failed A5 modulator drive board Measure the open circuit output voltage at the MODULATOR DRIVE BNC on the rear panel When the modulator drive is turned off the output should be about 6 4 volts DC When the modulator drive is on the output voltage should be about 6 volts AC Failure to turn on is probably caused by the A5 board but could also be caused by the CPU board Any of the following error messages indicate either a problem on the A3 CPU board or a problem in the firmware If the problem occurs continuously suspect the A3 board If the problem only occurs during a specific keystroke sequence it may be caused by a problem in the firmware These messages may be accompanied with a numeric error code and flashing LEDs on the front panel and on the A3DS2 LEDs Please note these messages and error codes when returning the instrument or board assembly to HP The messages are BUS ERROR Adr Error Code Err Zero Div Chk Instr Trap instr Priv violation Trace 1010 emulator 1111 emulator Processing Error HP 8757C E In Case of Difficulty il ON SITE SERVICE CALIBRATION Calibration can be quickly and easily performed with the HP 11613A or 11613B calibrator An HP 9000 series 200 or 300 computer with a compatible disk drive is also required The software provided with the HP 11613 includes bo
208. ctory SELECT TITLE lets you select a file title to be the active file title The current active file title is shown at the top of the CRT Use the analyzer knob to move the arrow to the file you wish to be the active file title Press SELECT TITLE PRIOR MENU returns the previous menu TITLE FILET allows you define a new file title The current active file title is displayed in the title area on the CRT To create a new file title first erase the active file title Then enter up to eight characters The new title is shown in the title area as you create it SELECT CHAR enters your character selection in the titie Turn the analyzer knob or repeatedly press the STP ONE RIGHT or STP ONE LEFT softkey until the arrow points to the character you desire Press SELECT CHAR and the character appears in the title peut Ra PR TAN Ae CRT GRAPHIC loads CRT graphics from disk This information must have been previously i Operating Reference HP 8757C E Sad HP 8757C E BACKSPACE deletes the last character entered in the title TERASE TITLE deletes the entire title STP ONE RIGHT moves the arrow pointer to the next character to the right ISTP ONE LEFT moves the arrow pointer to the next character to the feft DONE terminates entry oi the title and returns the previous menu IDELETE FILE deletes files from the directory Pressing DELETE FILE shows you the
209. curs readily when the interface comes in contact with any hard surface Never store connectors with the contact end exposed Plastic end caps are provided with all Hewlett Packard connectors and these should be retained after unpacking and placed over the ends of the connectors whenever they are not in use Extend the threads of connectors that have a retractable sleeve or sliding connector nut Then put the plastic end cap over the end of the connector Above never store any devices loose in a box or in a desk or a bench drawer Careless handling of this kind is the most common cause of connector damage during storage Calibration and verification devices and test fixtures shouid be stored in a foam lined storage case and protective plastic end caps should always be placed over the ends of all connectors Cables should be stored in the same shape as they have when they are used they should not be straightened and plastic end caps should be placed over both connectors Figure 1 summarizes these Hewlett Packard recommendations on handling and storing devices that have microwave connectors HANDLE AND STORE CONNECTORS CAREFULLY CONTACT END DOWN USE PLASTIC END CAPS Use foam lined storage cases if available Never store devices loose in a box or in a desk or bench drawer Figure 1 Handling and Storage NEVER PLACE CONNECTORS EXTEND THREADS FULLY Handling and Storage ELECTROSTATIC DISCHARGE
210. d the interrupts would not be active Line label for the routine that services the interrupts Serial poll the analyzer Reading the status byte of the analyzer clears the SRQ The CLEAR STATUS CS command could also be used Command the analyzer to output the key code of the last key pressed Read the key code Multi way branch on key code value If the key code is 32 then softkey 1 was pressed Print an appropriate message If the key code is 8 then softkey 2 was pressed Print an appropriate message If the key code is 0 then softkey 3 was pressed Print an appropriate message If the key code is 16 then softkey 4 was pressed Print an appropriate message If the key code is 41 then softkey 8 was pressed Print an appropriate message Exit the program by jumping to the end If the key code doesn t match any of the preced ing codes another key was pressed In this case the key code has to be for softkey 5 6 or 7 key codes 14 38 or 40 since these are the only other keys that can interrupt the computer Print an appropriate message End of multi way branch 13 Line 350 Re enter the program at the Wait srq label At that point the interrupts are re enabled and the computer waits for another SRQ Line360 End program execution Running program 8 1 Clearthe program memory of the computer and type in the program 2 Press RUN on the computer 3 Afterthe computer presets the analyzer and s
211. d be inspected visually with the center conductor collets in place and whenever the collet has been removed APC 7 is a U S registered trademark of the Bunker Ramo Corporation The collet itself should be inspected for edge or surface damage and for any signs that the spring contacts are bent or twisted If they are replace the collet When the collet has been re inserted verify that it springs back immediately when pressed with a blunt plastic rod or with the rounded plastic handie of the collet removing tool Never use a pencil or your finger for this purpose Sexed Connectors On sexed connectors especially precision 3 5mm APC 3 5 and SMA con nectors pay special attention to the female center conductor contact fingers These are very easily bent or broken and damage to them is not always easy to see Any connector with damaged contact fingers will not make good electrical contact and must be replaced Visual Inspection Scratches Light burnishing of the mating plane surfaces is normal and it consists of uniform shallow concentric scratches distributed more or less uniformly over the plated surface These are caused by the normal slight rotation of the mating planes against one another as the connection is made and generally do not affect performance Deep scratches are caused by individual hard particles generally metal or metal by product particles or burrs left from machining sliding across the mating plane surface and displa
212. d data same as M Monochrome display Marker or cursor to reference line Manual sweep mode on off Display the measurement menu Display the display menu Display the scale menu Display the reference menu Display the cursor menu Display the average menu Display the calibration menu Display the special menu Display the system menu Display memory data Manual calibration of DC detectors Non standard sweep mode on off Output cursor value Output trace data Output error status of display channel 1 Output error status of display channel 2 Outputidentity Output keycode of last key pressed Output learn string Output memory data Output normalized measurement memory data Output interrogated parameter value xx AF BW DA DB DC DR RL RD SD SL SO SP SK 95 9T Outputrotary knob value 732768 x value 32767 Outputstatus bytes Control output 1 on off Control output 2 on off Output CW value Plot channel 1 trace on external plotter Plot channel 2 trace on external plotter Plot channel 3 trace on external plotter Plot channel 4 trace on external plotter Plot all on external piotter System interface control on off Plot labels on external plotter Plot custom plot Plot grid on external plotter 727 52 Print all to monochrome printer except softkeys and CRT graphics Print tabular display data in monochrome Print tabular marker cursor data to external
213. d frequency difference value for the active channel is shown in the active entry area The frequency difference value is also shown in the frequency labels area When alternate sweep is engaged the cursor A frequencies for both sweeps are shown in the frequency labels area HP 8757C E Operating Heference 19 MAX positions the cursor to the maximum value point on the active channel trace for the current sweep The cursor is not continuously positioned to the maximum point When the measurement data is updated on the next sweep press MAX again to relocate the cursor to the maximum point MIN positions the cursor to the minimum value point on the active channel trace Ks eae HP 87876 ONLY Jem M M SEARCH presents the search menu and lets you search for a specific value in dB or dBm on the active channel Use this function with CURSOR A ON to find a power difference in dB Search functions cannot be used with SWR or AUX modes When SEARCH is pressed the search menu is presented and the active entry area shows the last set search value Change this value using the knob the STEP keys or the numeric keypad Terminate the entry with the dBm dB or ENT key Then use the SEARCH LEFT and SEARCH RIGHT softkeys to locate the entered value SEARCH VALUE allows you to change the search value as when SEARCH is pressed SEARCH LEFT causes the cursor to move to the first left positio
214. d off manual sweep control If the source is connected to the 8757 system interface MANUAL ON is selected automatically when the source is in manual mode or toggling to MANUAL ON will engage the source manual sweep mode This function also allows manual sweep control by a source not compatible with the 8757 system interface using a sweep input signal With MANUAL ON and the source in manual mode the analyzer provides a cursor whose vertical position represents amplitude and whose horizontal position can be manually swept from the source SYSINTF ON OFF toggles the analyzer s control of the 8757 system interface on and off When the analyzer is not the system controller another instrument on the 8757 system interface can control the instruments connected to the system interface The setting of this function is not changed at preset When off SYS INTF OFF is shown in the status line on the CRT STEP SW ON OFF toggles on and off step sweep mode Step sweep mode requires that the 8757 SYSTEM INTERFACE be connected and the SYSINTF ON OFF softkey be set to ON NOTE The STEP SW ON OFF softkey is only available with an HP 8340 or 8360 PRIOR MENU returns the previous menu PLT BUF ON OFF turns the plotter buffer on and off When the buffer is on and a plot softkey is pressed the analyzer is free to continue measurements while the data in the buffer is plotting Not all active functions are available during a plot and the entire proc
215. d over the private bus The analyzer also uses this connector to sense when the source has stopped the sweep HP 8757C E Operating Heference 61 NOTE Connection of a sweep signal to the SWEEP IN 0 10V connector is the minimum requirement for use of the analyzer as a receiver The POS Z BLANK must be connected to provide marker information on the screen If the source is connected to the analyzer through the 8757 system interface the STOP SWEEP must also be connected 6 The MODULATOR DRIVE connector provides a 27 778 kHz square wave signal nominally 6 V open circuit for driving an external modulator or the external amplitude or pulse modulation input of the HP 8350B Sweep Oscillator or the HP 8340 or 8341 series Synthesized Sweeper 7 The DAC OUT 0 10V connector is provided for future enhancements with later revisions of firmware It can also be used for troubleshooting purposes 8 The ADC IN connector is used to show an external voltage on the analyzer CRT using MEAS AUX The connector is also referred to as AUX input it can also be used for troubleshooting purposes 9 The CONTROL 1 and CONTROL 2 connectors provide digital output signals TTL open collector as a convenience for driving other peripheral equipment in an HP IB controlled system The CONTROL 1 signal is used as an oscilloscope trigger source when continuous loop service related tests are performed 3 40 The R G and B VIDEO OUTPUT connec
216. d then be rotated to make the connection Slight resistance is generally felt as the center conductors mate Alignment of precision 7mm connectors is made easier by the fact that the connector sleeve on one of the connectors must be extended fully and the sleeve on the other connector retracted fully in order to make the connection Extending the sleeve creates a cylinder into which the other connector fits if one of the connectors is fixed as on a test port extend that connector sleeve and spin its knurled connector nut to make sure that the threads are fully extended Fully retract the connector sleeve on the other connector Make a preliminary connection lightly Align the two connectors carefully and engage the connector nut over the exposed connector sleeve threads on the other connector Then turn the connector nut only to make the preliminary connection Let the connector nut pull the two connectors straight together Do NOT twist one connector into the other as one might drive a screw or insert a light bulb This is extremely harmful and can occur whenever the device body rather than the connector nut alone is turned When the mating plane surfaces make uniform light contact the preliminary connection is tight enough Do not overtighten this connection At this point all you want is a connection in which the outer conductors make gentle contact at all points on both mating surfaces Very light finger pressure no more than
217. data by outputing the test results to a plotter or printer Also obtain virtually unlimited storage of test setups and measurement data with the HP 8757C and an external disk drive Step one preset Selecting PRESET activates a self test routine when com pleted the analyzer returns to a pre determined state PRESET also initializes all instruments attached to the 8757 System Interface The major default conditions are listed in the table below Primary default conditions Analyzer Channel Measurement Display format Colors Scale Reference Number of points Detection mode Trace memories Save Recall memories Detector offsets HP IB addresses Cursor Modulation drive Averaging Smoothing Adaptive normalization Limit lines Source Frequency Sweep time Mod Printer Disk Applies only to the HP 8757C Channel 1 On Active Channel 2 On Channel 3 Off Channel 4 Off A on Channel 1 Bon Channel 2 C Option 001 or Bon Channel 3 on Channel 4 Displays the current measurement data Unchanged 20 dB division Reference Level equals 0 dBm Reference Position unchanged from previous setting 401 trace points AC Unchanged Unchanged Unchanged Unchanged Off Search Value equals 3 dBm On Off Off Off Unchanged Full span of source 200 ms On Plotter Abort all activity Abort all activity Abort ali activity Step two setup test connections The device und
218. de 10 Failure The A3 CPU cannot communicate with the A14 display interface board Either board could be bad or the ribbon cable W8 could be bad Since the A3 has been well tested already there is a 90 chance that the A14 board caused the failure No test equipment or re calibration is required HP 8757C E In Case of Difficulty 9 Error Codes 9 through 3 Failure All these error codes relate to the A14 display interface board Replacement of this board should cure the problem No test equipment or re calibration is required Error Code 2 Failure The A3 CPU has encountered an nterrupt it was not expecting or did not receive one it did expect Interrupts come from the A2 A3 A4 A6 or A14 boards The problem could also be on the motherboard Extensive troubleshooting is required to isolate this prob lem Either substitute known working boards for those listed or refer to the service manual for further information Error code 1 Failure A failure has occured with either the instrument verify routine or with the other tests listed Equipment required Varies with the failure INSTRUMENT VERIFY e RAM Replace the A3 CPU board e Instrument Bus See error code 11 e Display Bus See error code 10 Timer Replace the A3 CPU board ADC Measurement Check the 15V power supplies for accuracy If OK replace the A4 board e ADC Bit Check Same as ADC Measurement DAC Bit Check Same as ADC Measurement
219. discharge inspecting microwave connectors visually for damage dirt and contamination cleaning microwave connectors using compressed air and if required a cleaning solvent inspecting microwave connectors mechanically using precision connector gages and making connections with microwave connectors These general recommendations are summarized in Hewlett Packard Application Note 326 Principles of Microwave Connector Care One copy of this summary is also included with each copy of this Microwave Connector Care Manual bound separately for easy removal Besides the text it includes a quick reference card suitable for bench use Additional copies are available by contacting your local Hewlett Packard representative Part Two of the present manual provides detailed information on each main connector type it reviews the information in Part One that applies to each connector type and it explains special points about cleaning mechanical inspection connection and disconnection that apply to individual connector types it also gives the critical mechanical dimensions of each connector interface Your comments on all Hewlett Packard publications are welcome For your convenience a Reader Comment Sheet is included postage paid in the United States General Introduction 1 2 INTRODUCTION ay HANDLING AND STORAGE ELECTROSTATIC DISCHARGE VISUAL enint Part One Principles of Connector Care INTRODUCTION Dime
220. ds with either a line feed or a semicolon However there are alternate choices in the use of terminators Listed below in the syntax diagrams are all of the possible ter minators that can be used with the various input commands terminator Example C1IA ME If lt next fcn code Select channel 1 C1 measure the power at the A detector IA display the measured data ME on the CRT Input syntax 2 numeric function code function code followed by a single digit numeric terminator where m Ofunction off m 1functionon n decimal integer 1 through 9 q Example MD1 RP4SV9 If value unique to the particular function and explained under command description Turn the square wave modulation on MD1 set the reference position to the 4th graticule RP4 and then save the front panel setting into register 9 SV9 Input syntax 3 function code numeric where function code followed by a variable length numeric terminator lt units gt If d Variable length parameter including sign decimal point and exponent if desired The general fanatis D DDDDDE DD Resolution or range of d is explained under the particular command description When the value of d does not correspond to the function s resolution or range d will be rounded and assigned the closest allowable value Example AF64 RL 10DB SDO SDB lf Set the averaging factor to 64 AF64 set the
221. e Er I Une 6 start stop frequency 39 LABELS ON OFF softkey 38 learn string 5 IPG 16 IPV 19 learn string command QRG 15 imit lines UG 23 commands QRG 10 Lond cR RAM seen oats 28 p 28 delel P 28 sv cane sya ew oe ears 28 baad coe wenn 29 SAVE izle ka e E nS DIF 6 LIM LNS OFF softkey 29 LINE V 10 connector 62 line power problems DIF 2 line voltage 1 12 2 2 ISE ea dotted rii 15 LOAD FR DISK softkey 47 LOCAL key 42 local operation mode 6 iPG 3 IPV 4 LOCAL LOCKOUT QRG 6 3 4 LOG magnitude display 1 10 LWR LIM MEM softkey 28 M MANUAL softkey 224 manual changes supplement 1 3 MANUAL ON OFF softkey 41 manual operation QRG 6 IPG 4 manualsweep 41 marker cc eee data PE uS UG 9 MAX softkey 20 MEAS key 11 MEAS softkey RR RE Et eer E 12 SAVO pe pese hae we RE ES ES 44 MEAS MEM softkey Sin ees ea RES 13 SAVE MEI 44 MEAS MEM softkey calibration Lie 28 display sls RR A eyes 13 oz vea 48 MEAS M MEM softkey calibration
222. e This helps locate a problem in an instrument or its connections Clean the filter on the AC fan on the rear panel All instrument filters should be cleaned regularly at least monthly A clogged filter will cause overheating and consequent degradation of performance If the system cannot be controlled from the analyzer front panel 066 the power with the LINE switch on the analyzer Be sure that the source is compatible with the analyzer The HP 8350B Sweep Oscillator can be used with an HP 83500 series RF Plug in or with an HP 86200 series RF Plug in with an HP 11869A Adapter Some of these plug ins require an external modulator for AC compatibility with the analyzer The HP 8340 and 8341 series Synthesized Sweepers are also compatible with the analyzer Refer to Equipment Required But Not Supplied in Chapter 1 for a complete list of Source firmware versions that are compatible with the scalar analyzer HP iB Connections and Addresses If the instrument addresses are not set correctly or if the HP IB cables are not connected properly a system malfunction may occur Verify that the HP IB cables are functional Check for shorts and opens Make certain that the connectors are not damaged Make sure that the cables for the source and other peripherals are connected to the 8757 SYSTEM INTERFACE connector not the HP INTERFACE BUS connector Only a system controller should be connected to the HP INTERFACE BUS connector Make sure that the
223. e and it receives its listen address In remote all front panel functions are disabled except the LINE switch and the LOCAL key The LOCAL key can be disabled via the LOCAL LOCKOUT LLO com mand The state of the REN line is also sensed by the 8757 SYSTEM INTERFACE An instrument on the 8757 SYSTEM INTERFACE designated as the pass through instrument with the PTd command is placed in remote or local depending on thestate of the REN line When the analyzer is placed in local lockout the HP IB source is also placed in local lockout The analyzer goes to local when it receives the GO TO LOCAL GTL command or when the REN line goes high false It will also return to local when the LOCAL key is pressed unless the LOCAL LOCKOUT LLO command has been executed 1 HP 8757C only Service request The analyzer can initiate a service request SRQ whenever one of the following conditions exist m HP IBcommand syntax error m End of operation sweep or plot completed m Self test failed m Any front panel key pressed m Numeric entry completed HP IB or front panel Softkey only pressed m Battery voltagelow m Rotary knob activity Requested action not possible m Limit test failed For further information execute a serial poll or the OUTPUT STATUS OS command A serial poll operation consists of sending the analyzer its talk address sending the SERIAL POLL ENABLE SPE command reading the status byte on the
224. e device has a large gain the input power needs to be appro priately attenuated during calibration and measurement When testing a modulation sensitive device the DC detec tion mode must be utilized The HP 85025 series detectors operate in both AC and DC detection modes The AC DC mode softkey is located in the SYSTEM menu Selecting MODE AC DC will turn off the square wave signal on the source and set the HP 85025 series detectors to DC mode See the appendix for more information on AC versus DC detection Gain compression Measurement of gain compression is useful for characteriz ing the power handling capability of active devices such as amplifiers The 1 dB compression point of an amplifier is an indicator of the maximum output power possible before the gain non linearity and it s associated distortion becomes excessive Measurements to this point have all been made with a constant input amplitude and swept test frequency Gain compression measurements may be made in CW sin gle frequency or swept modes For the most accurate measurement at a particular frequency the power sweep mode of the HP 8350B may be utilized This allows the user to characterize a device at a CW frequency as a function of input power The following sequence is set up for the HP 8757C it utilizes the power sweep function to measure gain compression Since only two measurement channels are available on the HP 8757E the gain compression measurement may
225. e CRT in addition to all other information relating to channel 1 The channel menu can be turned off instructions for this function are explained under ISYSTEMI SYSTEM MENUS HP 8757C E Operating Reference 9 10 FUNCTION Keys gnam FUNCTION oo eres INSTRUMENT STATE RECALL PRESET TER ptem 5 j es HP STATUS a Figure 7 FUNCTION Keys The FUNCTION keys are shown in figure 7 The eight FUNCTION keys are used to engage functions and present softkey menus that generally apply to the active channel only These functions include measurement modes display formats scale factors reference levels and positions cursor position ing averaging calibration and special functions These functions are described in the following pages Operating Reference HP 8757C E MEAS MEASUREMENT MENUS HP 8757C E pem FUNCT ION Es Figure MEAS Key and Measurement Menus The MEAS key presents the measurement menus Figure 8 shows the measurement menus for the analyzer Either a single input or a ratio of inputs can be measured For example if A is pressed the displayed data is the measured value at input A in dBm If A R is pressed the displayed data is the measured value at input A in dBm minus the measured value at input R in dBm Since the values are in dBm alogarithmic subtraction is equal to the linear division A R The softkey function engaged a
226. e Sweep Compare Same as ADC Measurement Detector Control Same as ADC Measurement 10 In Case of Difficulty HP 8757C E OTHER TESTS EEROM Write Enabled Close switch A3S1 E This is a warning not a failure Battery Failure Replace the battery on the A3 board then cycle the power twice The error message should disappear if not replace the A3 CPU board Note The battery life should be about 10 years Unexpected Key Press Either a front panel key is stuck as indicated on the display or the A2 board is defective Check the indicated key or replace the Ai or the A2 board Configuration Error This generally does not indicate a failure Contact your local HP sales or service office for more information Other Problems Default calibration table used on A B C or R This indicates a need to recalibrate using the HP 11613A B If the problem persists it indicates a problem with the A3 CPU board If one input always seems bad and there is no detector offset active for that input suspect the logger board for that input A7 A8 A9 A10 for inputs A B C R respectively Verify this by interchanging the logger board to see if the problem follows the board Be sure to replace the boards in their original position if the problem does not follow the board itindicates a problem with the A4 ADC board Failure to sweep properly or Sweep Sync Errors indicate a problem on the 4 ADC board asssuming the source used is fun
227. e connector dry with a gentle stream of compressed air Cleaning Solvents Contact with solvents can affect the plastic dielectric that surrounds the cen ter conductor in SMA connectors and the plastic interior support beads in precision 3 5mm connec tors Generally this is not a problem if the solvent is applied with a cloth or swab and if the least possible solvent is used It can be a problem if the connector is sprayed directly with solvent or if the connector is immersed in solvent Both of these practices should be avoided If a connector does become wet with solvent during cleaning immediately invert the connector to allow the liquid to flow out then purge the remaining solvent using a gentle stream of compressed air This should be done slowly to prevent damage to the connector due to excessive cooling due to rapid evaporation of the solvent Allow the connector to return to room temperature before use If contact with the solvent has been prolonged inspect the plastic dielectric or support bead for signs of swell ing or deterioration before using the connector and discard any connectors that are damaged SMA and Precision 3 5mm Connectors GAGING SMA AND PRECISION 3 5mm CONNECTORS No protrusion of the shoulder of the male contact pin or of the female contact fingers in front of the outer conductor mating plane is ever allowable and sometimes a minimum recession is required Consult the mechanical specifications provided with the
228. e measurement errors HP 8757C E HP 8350B Sweep Oscillator _ Power Splitter y Directional Bridge mmi Device Under Test Detector Detector Scalar Network Analyzer Measurement setup for return loss and SWR The signal reflected from the DUT is most often measured as a ratio with the incident signal and can be expressed as return loss or SWR standing wave ratio These measure ments are mathematically defined as reflection loss reflected incident p return loss dB 20 logp SWR 1 p 1 p Preset Connections Connect DUT as shown in figure Controls Setup instrument Measurement CHANNEL 1 Activates channel 1 CHAN 20FF MEAS A R Sets up reflection measurement Source parameters CF 10 24 GHz AF 2 GHz POWER LEVEL 10 dBm dB Calibrate Perform reflection calibration Accesses calibration menu SHORT OPEN Sets up calibration connect short STORE SHORT Connect open STORE OPEN Stores calibration in memory of active channel DISPLAY Accesses display menu MEAS MEM Normalizes measurement trace Save 2 Save instrument state and calibration in register 2 Measurement Reconnect DUT and adjust parameters to enhance useability of measurement data Available only on the HP 8757C To deactivate a channel on the HP 8757E press it s hardkey until the channel turns off 17 Return loss The following figure di
229. e not changed during a PRESET IP command execution Reference position Trace memory Save Recall registers HP IB addresses Request mask Limit lines Title o 965 1 HP 8757C only 2 HP 8757C Option 001 only Display measurement data in log magnitude format Detector offset User defined plot 8757 System Interface control on off e Repeat autozero timer Display intensity Display colors Program 1 listing 10 REM INCLUDE GBSETUP 20 CLS 30 15 amp 7 40 Snak 716 50 CALL IOTIMEOUTCISC amp 1017 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 60 CALL IOABORTCISC amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 70 CALL IOCLEARCISC amp IF PCIB ERR NOERR THEN ERROR PCIB BASERR 80 CALL IOREMOTE Sna IF PCIB ERR NOERR THEN ERROR PCIB BASERR 90 GOSUB PAUSE 100 CALL IO REMOTE CSna amp IF PCIB ERR lt gt NGERR THEN ERROR PCIB BASERR 110 CALL IOLLOCKOUTCISC4 amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 120 GOSUB PAUSE 130 CALL IOLOCAL Sna IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR 140 GOSUB PAUSE 150 A IP CALL IOQUTPUTSCSna amp AS LENCA 22 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 160 END E 170 PAUSE DO UNTIL INKEY CHR C132 LOOP 180 RETURN Program 1 explanation Line 10 Cail the QuickBASIC initialization file QBSETUP which is the setup program for the MS DOS HP IB Comma
230. e paper runs out If this happens it will significantly slow system performance Do not set the HP IB address of any instrument on the 8757 system interface to a value one digit greater or smaller than the analyzer s HP IB address To do so will cause conflict with the analyzer s passthrough address See Remote Operation for more information on passthrough addresses INACCURATE OPERATION If the analyzer is functional but you doubt the accuracy of the measurements the problem may be with calibration or with the modulation frequency of the input signals Calibration Make sure the system is correctly configured for the detectors connected The system automati cally reconfigures whenever a detector is replaced or exchanged Press CAL CONFIG SYSTEM The analyzer will determine the types of detectors connected and calibrate each input Ifyou are using DC detection make sure the detectors are zeroed to compensate for the effects of DC drift Press CAL DC DET ZERO and choose manual or automatic zeroing e Make sure the correct value of detector offset is entered The status line shows which detectors have an offset entered Press CAL DET OFFSET and verify or change the offset values for each detector input Remember that instrument preset does not reset the offset values to zero For further information on calibration procedures see CAL Calibration Menus in the Operating Reference In Case of Difficult
231. e pen and draw the outline of the analyzer Draw the CRT of the analyzer Draw the connections from the source to the DUT Draw the connections from the DUT to the analyzer Draw the DUT an amplifier Move to the bottom left corner of the CRT Place the analyzer and the source in local mode Perform error trapping End program execution Define a subroutine that outputs commands to the analyzer Perform error trapping Return from the subroutine Define a subroutine that addresses the analyzer as a plotter Perform error trapping Return from the subroutine Running program 11 ir Clear the screen of the computer and type in the program Press ALT IR S on the computer After the analyzer and source are preset the CRT is blanked except for softkeys First a grid is plotted on the CRT While this isn t neccessary for our connection diagram it does give you a good indication of where the X and Y coordinates are on the analyzers CRT The labelling is added The labels CONNECTION DIAGRAM and DUT are written using the analyzer CRT s internal character set All of the lines are plotted on the analyzer s CRT If brighter lines are desired draw each line twice or select different pen numbers The analyzer is placed in local mode with the front panel and the softkeys active To access the graphics on off capability press SAVE on the analyzer to show the save menu Press the STORE TO
232. e to return it to normal swept operation Any command can be sent via passthru mode to any instrument on the 8757 SYSTEM INTERFACE and any data can be read Service requests and parallel polls do not pass through the analyzer Program 4 cursor operations To enhance the speed and accuracy of measurements the analyzer contains a built in cursor that displays the frequency and magnitude of a trace at any given point To make measurements even more efficient the cursor may be set to the maximum or minimum point on the trace simply by pressing a softkey These cursor functions are available 5 via HP IB commands With a computer the cursor may be turned on and off its position 0 to n 1 where n is the number of points per trace set its value and position read and set to the maximum or minimum point on the trace The cursor functions all apply to the active channel You have complete control over cursor operations via HP IB Cursor programming is especially useful for measuring parameters like flatness and maximum power where you are interested in the highest and lowest point on the trace For measuring parameters such as 3 dB points and other specific points not a maximum or minimum it is more efficient to use either the cursor search functions available on the 8757C only or to read the entire trace and search for the points you need Program 4 listing 10 PRINTERIS1 20 Start_freq 01 30 Stop freq 20 40 ASSIGN S
233. e with HP scalar analyzers utilizing the 8757 System Interface This function provides the ability to make real time measurements alternating on successive sweeps between the source s current front panel state and any of the states stored in memory Simultaneously the device s response may be displayed over two independent frequency ranges or two different power levels When tuning a filter there is an alignment tradeoff between passband ripple and out of band rejection Real time adjust ments may be made by displaying the passband on one channel and the full filter response on another channel as shown in the figure below Amplifier manufacturers may compare small signal gain to large signal gain for real time 1 dB gain compression measurements The following lists important considerations for setting up alternate sweep measurements Only thesource settings frequency and power of channels 1 and 2 are successively changed the current analyzer settings remain the same The active channel is swept over the source s current front panel settings while the other channel is swept over the alternate register s source settings The measurement parameters the information in the mode label area of channels 1 and 2 in the active regis ter should be set up the same as that in channels 1 and 2 in the register with which the active register will be alternated The analyzer settings such as the number of points AC DC detect
234. earn string is 150 contiguous binary bytes that does not end with a cr If since these could actually be part of the learn string information The computer must read all 150 bytes and this format ensures that it will Program the source to output its learn string Line 130 Read the source learn string into the string Lswpr Notice the 90A format As on line 110 the computer must read the entire source learn string For the HP 8350B Sweep Oscillator itis 90 bytes long Line 140 Presetthe analyzer and source to clear the instrument states Line150 Prompt the user and wait for the Continue key press Line160 Program the analyzer to accept its learn string then send the learn string Notice the 2A 150A format ensures that the IL command and the 150 bytes of the learn string are sent continuously The HP 8757C E expects the learn string to start immediately after the IL command Line170 Program the source to accept its learn string then send the learn string Notice the 2A 90A format As on line 160 this ensures that the source learn string is sent properly Line 180 Re address the analyzer to exit passthru mode and continue sweeping Line190 Set the analyzer and source to local mode Line200 End of execution Running program 10 1 Clear the program memory of the computer and type in the program 2 Press RUN on the computer 3 The computer stops and displays SET UP SYSTEM PRESS CONTINUE
235. ect Commands 3 of 6 4 HP IB CANT Plot 2 Plotter buffer on off 1 Plot All plots entire display except user graphics on an external plotter 1 Plot channel 1 trace 1 Plot channel 2 trace 1 Plot channel 3 trace 1 Plot channel 4 trace i Plotonly labels on a external plotter 1 Plot only the grid on an external plotter 3 Specify custom plot dis decimal integer from 0 to 255 representing one byte Each bit of this byte specifies what is to be plotted If a bit is set to 1 that item will be plotted else it will not be plotted decimal decimal bit value action value bit action 0 15 1 Scale Trace P1 and 4 16 Trace 4 P2 define grid size 5 32 Grid 1 2 1 6 64 Mode Labels 2 4 Trace 2 7 MSB 128 Frequency 3 8 Trace 3 Labels 1 Plot custom plot on an external plotter Print PRI Print entire graphics display except user graphics on external graphics printer PR2 PR3 Print tabular display data in monochrome Print tabular marker cursor data on external printer Print all to color printer except softkeys and CRT graphics Erase limit lines for active channel only channels 1 and 2 are valid Limit is single point specified by s The string s includes the segment number 1 to 12 in the x axis value the upper limit value and the lower limit value in the following format LP seg no x value x units upper limit y units lower
236. ectly in decibels dB Preset Connections Connect the DUT to the network analyzer as shown in the previous configuration Controls Setup the measurement Measurement CHANNEL 1 Activates channel 1 CHAN 2OFF Turns channel 2 off MEAS B R Sets up ratio measurement Source parameters CF Activates the center frequency function 10 24 GHz Sets center frequency to 10 24 GHz AF Activates frequency span function 2 GHz Sets frequency span to 2 GHz POWER LEVEL Activates power level function 10 dBm dB Sets power level to 10 dBm Calibrate Perform thru calibration CAL Accesses calibration menu THRU Sets up calibration remove DUT connect thru STORE THRU Stores calibration in active channel s memory DISPLAY ccesses display menu MEAS MEM Normalizes measurement trace Save Save the instrument states and calibration SAVE Presents SAVE REG in the display s active entry area 1 Saves instrument state and calibration in register 1 Measurement Reconnect the DUT SCALE Activates scale function AUTOSCALE Provides quick convenient scaling of the measurement data Available only on the HP 8757C To deactivate a channel on the HP 8757E press it s hardkey once if it s the active channel twice if it is on but not active until the channel turns off 1i Raising the reference position to the top half of the grid and adjusting the reference level to 0 dB
237. ectors once B A ratio measurement B C ratio measurement Restore CRT to normal mode Blank frequency labels secure frequency mode frequency labels cannot be restored Blank ali labels Blank active channel trace Blank softkey labels Blank ali except user CRT graphics Blank title Blank mode labels Blank the active entry area Blank the limit lines Blank all except user CRT graphics softkeys B R ratio measurement Overall display brightness Display the search bandwidth on the CRT Channel off Channel 1 on active Channel 2 on active Channel 3 on active Channel 4 on active C A ratio measurement C B ratio measurement Set channel 1 color Set channel 2 color Set channel 3 color Set channel 4 color Cursor delta on off Set labels color Set background color Set grid color Set warning label color Perform system configuration of detectors and channels Color list black Color list green Color list blue Color list red Color list salmon Color list white Color list yellow Cursor to minimum 2 HP 8757C Option 001 only detector C 3 Limit line functions valid only for channels 1 or 2 HP 8757C only 22 Brightness adjust one color Color adjust one color Tint adjust one color C R ratio measurement Clear status bytes Auto system calibration on off Cursor o
238. ed continuous wave CW signal provides the stimulus to the device under test This signal is rectified by the detector and then transformed into an AC detectable signal The transformation is accomplished by the detector s chopping and sampling circuitry The rectified signal is chopped at 27 778 kHz and made to resemble a square wave Hewlett Packard Interface Bus The HP 8757C E is factory equipped with a remote programming interface using the Hewlett Packard Interface Bus HP IB Remote operation of the instrument allows you the same control of the instrument as with local operation except for control of the power line switch and internal tests Remote control is maintained by a controller that sends commands to and receives data from the analyzer using HP IB A tutorial description of HP IB is available from Hewlett Packard See Replace able Parts for ordering information See also Remote Operation which describes the HP IB capabilities of the analyzer 8757 System Interface The analyzer can control a plotter printer or source through the 8757 System Interface in local and remote operation modes A separate interface connector for the 8757 System Interface is located on the analyzer rear panel Itis a dedicated HP IB port used exclusively by the analyzer Do not connect a controller to this connector instruments are connected to the 8757 System Interface with HP IB cables OPTIONS AVAILABLE The following analyzer options are av
239. ed is not changed as the trace is expanded and the calibration data is interpolated between the available points Adaptive normalization should not be used if the calibration trace varies rapidly with frequency An asterisk is shown in the status symbols area of the model labels area for any channel that has adaptive normalization engaged and is in MEM or MEAS MEM I display mode If the trace is expanded beyond the range of calibration the calibration data outside that frequency range is extrapolated as a straight line from the calibration data at the start and stop frequencies in this case a U is 2500 in the status symbols area MORE presents a second system menu MOD ON OFF toggles on and off the 27 778 kHz modulation drive output on the rear panel of the analyzer a aE a wo HE BFE 7G ONLY oem terre ir tennant CH ME NU ON OF EJ toggles on and off the channel menu accessed from the channel keys in this state pressing a CHANNEL key activates the channel but the existing menu presentedon the CRT does not change This is a convenient mode in which to define the measurement parameters for both channel 1 and channel 2 because it saves keystrokes i To turn off a channe when the channel menu is off press the channel key twice The first press activates ine channel ihe second press turns it off Pressing the CHANNEL key again turns on the channel and activates it n the chann
240. el 1 color Set channel 2 color Set channel 3 color Set channel 4 color Cursor delta on off Set labels color Set background color Set grid color Set warning label color Perform system configuration of detectors and channels Color list black Color list green Color list blue Color list red Color list salmon Color list white Color list yellow Cursor to minimum Brightness adjust one color Color adjust one color Tint adjust one color C R ratio measurement Clear status bytes Auto system calibration on off Cursor on off CW mode on off Cursor to maximum Detector A offset set to d Detector B offset set to d Detector C offset set to d Set default colors Set disk format to ASCII Set disk format to binary Display Hold on off of the active channel trace Set disk HP IB address Set disk unit number Set disk volume number Delete file from disk AH inputs set to DC detection All inputs set to AC detection Step down decrement Detector R offset set to d Display trace data in log magnitude Display trace data in standing wave ratio SWR format Erase all save recall registers Start frequency label Stop frequency label Format data ASCII Format data binary HP BASIC compatible Format data extended ASCII Format data binary PC compatible Logarithmic dB cursor format SWR cursor format Step sweep on off Inp
241. el menu press SYSTEM MORE CH MENU ON CLEAR SAV RCL clears all of the save recall registers and presets the analyzer If a compatible source is connected to the 8757 system interface itis also preset and its save recall registers are cleared When this softkey is pressed the message IF YOU WANT TO CLEAR ALL REGIS TERS PRESS YES appears on the CRT and another menu is presented CLEAR YES clears all save recall registers and returns the channel menu in the preset instrument state NO returns the previous system menu with all save recall registers intact NOTE For high security environments the analyzer can be configured to clear all save recall registers each time the instrument is powered down This eliminates the possibility of confidential information remaining in the registers To enable this function follow these steps e Remove the battery A3BT1 from the CPU board This will prevent storage of any register data The internal self test now indicates a battery failure upon power up install a wire jumper A3W2 on the CPU board just below U2 This jumper will signal the CPU to skip the battery self test and normal operation resumes A warning message SAVE RECALL registers defaulted will briefly appear upon each power up cycle Removing the battery does not affect the internal calibration of the analyzer only the save recall registers 40 Operating Reference 8757 SWEEP MODE p
242. elected to illustrate many of the operating modes of the HP 8757C E and the simplicity of their design The bandpass filter HP Part No 0955 0446 utilized as the device under test in many of the examples demonstrates the techniques for meas uring most common devices Chapters 4 and 5 describe advanced features such as limit test ing for device evaluation and how to use the alternate sweep capabilities of the HP 8350B and HP 8340B 8341B sources Chapter 6 illustrates the HP 8757C s external disk save recall capabilities while chapter seven covers special functions such as color selection and frequency blanking This document also includes an appendix that describes the capabilities and advan tages of the AC and DC detection modes The HP 8757C E Operating Manual HP Part No 08757 90073 has more complete operating information Use this reference for further information on any topic cov ered in this User s Guide Programming information is provided in the Quick Reference Guide HP Part No 08757 90077 in the Introductory Programming Guide for Microsoft QuickBASIC 4 0 HP Part No 08757 90076 and for Series 200 300 computers HP Part No 08757 90075 Microsoft is a U S registered trademark of Microsoft Corp How to use this guide To gain the most benefit from this User s Guide it is recom mended that you proceed sequentially through the guide starting with chapter 1 and ending with chapter 7 Each chapter buiids upo
243. ement Memory Memory 8 Cursor Search osea Ge woven poaa 8 On Site Service Repairs 8 Main Error Gods c vota tetra codes 9 instrument Verify osse een E x Y ERE I 10 Other Tests vie edant ucc ica medi On Site Service Calibration Og Dua uan sd 12 CONNECTOR CARE Connector Care manual GLOSSARY INDEX Table of Contents LIST OF ILLUSTRATIONS SECTION 1 GENERAL INFORMATION HP 8757C Option 001 Scalar Network Analyzer and Accessories Supplied Typical Serial Number Piate SECTION 2 INSTALLATION Power Line Module x Option 908 Rack Mounting without Front Handles Option 913 Rack Mounting with Front Handles 8757 SYSTEM INTERFACE Connector and HP INTERFACE BUS Connector and Pin Configuration Analyzer to HP 8350B Sweep Oscillator Interconnections Analyzer to HP 8340 and 8341 series Synthesized Sweeper Interconnections HP IB Address Label Preparation of Instrument for Shipment Packaging for Shipment Using Factory Packaging Materials oos eA er acea Seu emu ORE SECTION 3 OPERATION Local Operation Operating Reference The HP 8757C Option 001 Front Panel The Analyzer CRT Mode Labels Description Status Line Description CHANNEL Keys CHANNEL Keys and Channel Menu FUNCTION Keys poner dee EE dO U
244. emory Memory This function can only be used with ratio measurements e M MM n i H M M ME P B757C ONLY Jemen Cursor Search Search functions differ from normal cursor operation The cursor is updated with every sweep to reflect the present amplitude response at the cursor frequency In search left search right and modes the trace is put into hold after the first search and the trace freezes on the CRT This makes it possible to inspect the trace without it changing MERERI There are two ways to exit search mode and return to the normal cursor mode Press PRIOR MENU CURSOR OFF Or press CURSOR ON SITE SERVICE REPAIRS On site analyzer repair includes assembly level troubleshooting replacement of the defective assem bly and possible re calibration The equipment required to re calibrate varies with the failure The service manual gives complete troubleshooting instructions This guide will quickly resolve 90 of the failures where error messages are displayed and other obvious failures such as a dead A B or R input The motherboard must be functional with no opens or shorts This guide is organized by error code or error message Error code interpretation is described in Error Codes Notes on Equipment Required Where the HP 11613A B Calibrator is listed as required equipment a computer with disk drive is also required Only an HP 9000 ser es 200 300 Compute
245. en G3 output to the monitor V 2 12 installation HP 8757C E HP IB ADDRESS SELECTION The analyzer can be operated directly by the front panel controls or by remote control In the remote control mode the controller and the analyzer communicate through HP IB The controller identifies the analyzer by an HP IB address Each instrument on the bus must have a unique address code Do not set the analyzer address to the same address as any other instrument connected to the 8757 System Interface Thirty different address codes are available 0 through 29 The analyzer is shipped from the factory presetto address 16 In all standard analyzers the HP IB address is read at first power on by the central processing unit CPU from firmware and stored in memory The analyzer HP IB address will not change until the value in memory is changed through the front panel functions or when firmware is changed in the analyzer With a firmware change the HP IB address again defaults to 16 Read the analyzer HP IB address on the CRT by pressing LOCAL front panel key 8757 softkey To change the HP IB address at this point enter the new address number using the entry keys on the front panel When the correct numbers have been entered press ENT The CRT will now show the new address This address is stored in memory and is not changed by turning the LINE switch off or when the analyzer is preset HP IB address labels s
246. eneral Information This section includes a brief description of the instrument and available options safety considerations accessories supplied and tables of specifications and supplemental performance characteristics Section 2 Installation This section provides information for initial inspection preparation for use line voltage and fuse selection connectors and cables rack mounting interconnections with sources and with external monitors storage and shipment Section 3 Operation This section is divided into three subsections Local Operation Remote Operation and Case of Difficulty Firmware revision history can also be found in this section Local Operation contains feature descriptions of the analyzer softkey menu structure maps and instructions for typical measurements Remote Operation provides information on remote operation of the analyzer with a controller The programming notes identify programming commands and provide example programs to demon strate remote control of the analyzer In Case of Difficulty provides first line problem identification and troubleshooting information Connector Care This part of the manual contains a separately bound guide to care and cleaning of microwave connectors Glossary and index The Glossary contains definitions of terms that are unique to the manual or that require special understanding The Index is an alphabetized subject guide to the manual The separate se
247. ent setup for channel 1 except replacing the AF with the span of the passband Out of band rejection The wide dynamic range of the HP 8757 allows it to measure stopband rejection over 76 dB below the passband response Maximum dynamic range requires proper selec tion of the measurement port power level and averaging factor The MAX and MIN functions in the cursor menu allow the user to quickly determine the dynamic range of the device under test Usable dynamic range is the difference between the meas urement port s output power and the HP 8757C E s noise floor Optimizing dynamic range therefore involves choosing the optimum input and output power to the device reducing the analyzer s noise floor Selecting the power level The accompanying figures show how power test levels deter mine the available measurement range In the first case the output power of the source is 5 dBm The device appears to have approximately 50 dB of rejection in the stopband In the second case the output power of the source is 10 dBm Notice this increases the measurable dynamic range to gt 65 dB We have now demonstrated that the stopband rejection of this device is gt 65 dB CHE B U M 0 0 08 7 00 gu Sp 88 58 5 10 0 da LOG ds OP SIM CLIN aa lg nag 66 53 dB GF 3 cns i H i P i nA T
248. ents made for each device over time Noticeable differences from one set of measurements to the next may indicate errors in measurement technique or that the connector is damaged and needs to be replaced Mechanical Inspection MAKING CONNECTIONS Align connectors carefully Make a preliminary connection lightly Turn the connector nut ONLY in making connections Do not rotate devices in making connections Use a torque wrench for the final connection Operator skill is essential in making good connections The sensitivity of modern test instruments and the mechanical tolerances of the precision microwave connectors that are used today are such that slight errors in operator technique that once went unnoticed now have a significant effect on measure ments and measurement uncertainties Making good connections is easy if a few simple principles are kept in mind all connectors must be undamaged clean and within mechanical specification e the connectors must be precisely aligned with one another and in flat physical contact at all points on the mating plane surfaces the connection must not be too tight or too loose lateral or horizontal bending force must not be applied to the connection nor should any connection ever be twisted Making Connections 23 24 General Connection Technique The steps to follow generally in making microwave connections are shown in Figures 11 and 12 For illustration a fixed load that ha
249. environments and for applications in which many connections and disconnections must be made They are among the most popular general purpose connectors used in the dc to 18 GHz frequency range HP Precision Type N connectors are stainless steel or beryllium copper Type N connectors developed for measurement applications Unlike precision 7mm connectors Type N connectors Figure 18 are sexed connectors The male contact pin slides into the female contact fingers and electrical contact is made by the inside surfaces of the tip of the female contact fingers on the sides of the male contact pin The position of the center conductor in the male connector is defined as the position of the shoulder of the male contact pin not the position of the tip Type N connectors differ from other connectors in that the outer conductor mating plane is offset from the mating plane of the center conductors The outer conductor sleeve in the male connector extends in front of the shoulder of the male contact pin When the connection is made this outer conductor sleeve fits into a recess in the female outer conductor behind the tip of the female contact fingers No Type N connector should ever be used when there is any possibility of interference between the shoulder of the male contact pin and the tip of the female contact fingers when the connectors are mated in practice this means that no Type N connector pair should be mated when the separa tion between the ti
250. ep Oscillator with plug in or HP 8340B 41B Synthesized Sweeper 1 HP 9000 Series 200 300 Computer with BASIC extensions 2 0 2 1 3 0 4 0 5 0 or 5 1 and at least 64K bytes of free user memory 1 HP 85027A B C D E Directional Bridge 1 HP 11664A E Detector or HP 85025A B D E Detector with connector type to match bridge and test device 1 Shielded open circuit with connector to mate with bridge 1 Short circuit with connector to mate with bridge 3 HP 11170C BNC cables 122 cm 48 in 4 are needed with HP 8340B 41B 2 HP10833A B C D HP IB cables 1 Test device 8757 SYSTEM INTERFACE HP 11555Rn DETECTOR CTYPE N APC 7 TO TYPE N FEHRLE ADAPTER BAND PASS FILTER Figure 1 System Connections Set up Connect the instruments as shown in figure 1 The following procedure sets the HP IB addresses of the instruments to operate properly with the programs contained in this guide 1 Turn on the 8350B Sweep Oscillator Press SHIFT LCL The FREQUENCY TIME display shows the current HP IB address of the source If it is not 19 press 1 9 to set the address to 19 The HP 8340B or 8341B Synthesized Sweeper operates the same although the address is displayed in the right hand display area 2 Power on the HP 8757C E Scalar Network Analyzer The current HP IB address is shown in the active entry area of the CRT If it is not 16 press LOCAL 8757 1
251. er Value Cursor Value Measurement Data Output Normalized Data Outputs binary data string 150 bytes long which completely describes instrument state Can be stored in ASCII character string and later input to restore that instrument state Outputs the present numeric value of the function selected xx is the function code to interrogate AF BW DA DB DC DR RL RP SD SL SO SP SR SS ST Outputs cursor or cursor A amplitude and horizontal position Format set by the FDx FRx and DSx commands Output measurement data no of data points is the same as the no of points trace Format set by FDx command With the OD command data is returned in units of dB or dBm unless in SWR trace format units are SWR in general whenever a measurement is defined dBm dB SWR one or more sweeps must be taken before the data is valid Output memory data no of data pointsis the same as the no of points trace Format set by FDx command Output normalized data measurement memory no of data points is the same as the no of points trace Format set by FDx command Not valid for SWR trace mode Output CW value Non swept mode SW0 or SW2 must be set Format set by FDx command Data is returned in dBm or dB even if SWR trace format is used 150 B EOI D DDDDDE DD IF ASCII Data DD DDD DDDD 1f Extended ASCII DDD DDD DDDD 1f Binary Data BB
252. er will output one 8 bit byte giving the present status of display channels 1 or 2 respectively This can be used with the HP 8757C to determine which channel has failed the spec ified limit test if limit lines were enabled Data The analyzer outputs data from the designated display chan nel in one of three formats ASCII formatted data Extended ASCII formatted data and binary formatted data The two ASCII formats are the more general purpose formats and are the easiest to interpret the output values Binary formatted data provides the fastest data transfer rates and is usually the choice when transfer speed is a major concern The data for matis selected by using the FDx commands The data format must be selected before a data transfer is attempted Identity Selected with the OI program code the analyzer will output a message which identifies it from other scalar network ana lyzers Both the model number and the software revision are provided This is helpful in system applications where soft ware is written to run on more than one scalar network analyzer Trigger The HP 8757 does not respond to the group execute trig ger GET message Clear The device clear DCL and selective device clear SDC mes sages clear all status bytes the request mask the HP IB of the analyzer and the 8757 SYSTEM INTERFACE Remote Local The analyzer goes to remote when the remote enable REN lineon the interface is low tru
253. er and source are both preset Note that the computer sent the instrument PRESET command only to the analyzer The analyzer in turn preset the source Remember to preset both the analyzer and the source you only need to send the instrument PRESET command to the analyzer Do not send instrument PRESET to the source by way of passthru mode discussed in program 3 Program 2 controlling the front panel All front panel keys and most of the softkeys of the analyzer may be programmed remotely via HP IB For example you can program the scale per division reference level and s reference position for each channel Program 2 listing 10 ASSIGN GSna TO 716 20 ABORT 7 30 CLEAR Sna 40 OUTPUT Sna IP 50 PAUSE 60 OUTPUT gSna C1C0C2 70 PAUSE 80 OUTPUT GSna SD10 90 PAUSE 100 OUTPUT GSna RL 10 110 PAUSE 120 OUTPUT GSna RP4 130 PAUSE 140 OUTPUT Sna IA 150 PAUSE 160 OUTPUT GSna C0C1 SD5 RP4 RL 5 170 END Program 2 explanation Line10 Assign an I O path to the HP IB address of the HP 8757C E Line20 Abort any transfers and clear the HP IB interface of the computer N Line30 Clear the HP IB interface of the analyzer Line40 Preset the analyzer and the source Line50 Temporarily stop execution Line 60 Select channel 1 and turn it off Turn channel 2 on Line 70 Temporarily stop execution Line 80 Set the scale per division to 10 dB No terminator is needed because this
254. er test DUT determines the actual system configuration the three optionally four inputs offer the user a variety of possibilities Simple insertion loss or gain measurements may be made with only a power splitter Reflection measurements require a directional bridge or coupler The following figure presents a block diagram of a basic scalar coaxial system configured for ratio reflection and transmission measurements Adapters attenuators isolators or other components may also be required depending on the actual DUT and the measurement parameters being charac terized Connector savers high quality adapters should be utilized whenever possible to preserve test ports of higher cost components i e directional bridges thus minimizing damage from repeated connect disconnect cycles HP 8757C E HP 83508 Scalar Network Analyzer Sweep Oscillator i Directional 1 Bridge Device Under Test Detector NH Detector Step three set system control settings 1 Select measurement input 2 Set up source parameters Following preset channel one is active and channel two is on Use the MEAS key to select the appropriate single or ratioed measurement input for characterizing the desired parameters Use the controls of the source to set the start and stop fre quencies that correspond to the frequency range of the device under test The 8757 System Interface bus allows the HP 8757C E to act as system cont
255. ern 39 error output display status QRG 5 error codes DIF 2 extended service see options extended status byte QRG 21 external detector calibration 25 modulation 2 11 detector calibration commands QRG 11 monter isole R9 v y wees 2 12 see also video output EXT DET CAL softkey 25 F file delete sae ur ASA 45 49 directory fice ccc eer s 45 48 lille ibd loco wie 45 48 FILE DIRECT softkey recall o ver EV PA ER 48 SAVE c eg lell ROSE ee eee 45 file extensions QRG 20 fiter cleaning ossis DIF 3 firmware compatibility 1 7 firmware revision history HP 87576 ites 3 2 HP 87576 3 3 FLAT LIMIT softkey 28 format datacommands ORG 14 trace return 1055 13 UG 18 trace SWR 13 UG 18 FREQ LABELS softkey 35 FREQ LBL OFF softkey 38 frequency bianking labels 38 blanking readout 38 QRG 7 UG 24 CUISOM Judd 19 marker UG 9 secure mode 38 QRG 7 UG 24 front panei key codes QRG 21 KEYS cures ivre RR IRE RED doe Oe 4 khOD ere ERA A E n 30 menus softkeys commands QRG 12 remote operation IPG 5 IPV 5 FUNCTION keys 4 10 function select commands 8 13 fuse selection
256. ery small container and replace the supply often Other solvents including types of liquid Freon and isopropanol that contain additives should not be used Acetone methanol denatured alcohol and chlorinated hydrocarbons such as trichloroethylene TCE are all harmful to the plastic dielectric support beads in microwave connectors Alcohols such as ethanol or isopropanol are less harmful than methanol but are not always easy to obtain in suffi ciently pure form Ethanol is often denatured with methanol isopropanol especially in the common form of rubbing alcohol often contains large amounts of water and additives such as glycerine oils and perfume Pure liquid Freon is inexpensive it is easy to obtain and use and with very few excep tions is not harmful to plastic parts i COMPRESSED AIR LIQUID FREON HP Part Number 8500 2503 HP Part Number 8500 1251 i COTTONSWABS LINT FREE CLEANING CLOTH HP Part Number 8520 0023 HP Part Number 9310 4242 Figure 3 Recommended Cleaning Supplies Cleaning 10 Using Solvents Whichever solvent is used always use the least amount of solvent possible and carefully avoid wetting the plastic support bead inside the connector and blow the connector dry immediately with a gentle stream of compressed air Support beads are easily damaged by solvents Use solvents in liquid rather than spray form If a spray must be used always spray the solvent onto a cloth or swab never directly
257. es Synthesized Sweeper can only be saved or recalled on disk with firmware Revision 3 1 System Interface On Off The analyzer uses the 8757 system interface bus to control the other instruments connected to the system interface The 8757 system interface should be on in most applications To verify that it is on check the CRT status line SYSINTF OFF appears when the system interface is off When the system interface is off the analyzer has no control or knowledge of the existence of any HP IB instrument connected to this interface To turn the system interface on press SYSTEM MORE SWEEP MODE SYSINTF ON Itis importantthat no two instruments connected to the system interface have the same HP IB address If this occurs the analyzer may freeze operation until the situation is corrected 1 Address Selection in Installation explains how to verify or change the addresses the analyzer is expecting When the system interface is off the following analyzer system functions are not possible Autozero of DC detectors Alternate sweep Start stop cursor frequency annotation System save recall and preset System CW and manual sweep modes Adaptive normalization Hard copy plot and print Disk access If you try to plot or print with the system interface turned off the analyzer will perform an instrument preset after a few seconds 1 HP 8757C only HP 8757C E In Case of Difficulty 7 8 Measurement M
258. es the internal plotter buffer of the analyzer New softkey STEP SW ON OFF has been added to the SYSTEM key menu The corresponding remote command is FSm This function enables the step sweep mode when using an HP 8340 or HP 8360 and connected to the 8757 SYSTEM INTERFACE New system interface compatibility with HP 8360s including master slave source configurations HP 8757C E Operation 3 3 3 4 Section 3 Operation CONTENTS 1 Introduction 2 HP 8757C Firmware Revision History 3 HP 8757E Firmware Revision History LOCAL OPERATION Operating Reference e HP8757C E User s Guide REMOTE OPERATION e introductory Programming Guide for the HP 8757C E Scalar Network Analyzer with the HP 9000 Series 200 300 Desktop Computer BASIC Introductory Programming Guide for the HP 8757C E Scalar Network Analyzer with the HP Vectra Personal Computer using Microsoft QuickBASIC 4 0 e Quick Reference Guide for the HP 8757C E Scalar Network Analyzer IN CASE OF DIFFICULTY INTRODUCTION This section contains operating information organized as follows The Local Operation subsection contains the Operating Reference and the User s Guide The Operating Reference explains the analyzer s front and rear panel operating features and front panel key and softkey functions It also contains the Operator s Check which is used to verify that your analyzer is functioning properly The User s Guide contains typical measurement setups and example t
259. esired draw each line twice 5 Finally the labeling is added The label CONNECTION DIAGRAM is done using the analyzer CRT s internal character set The DUT label uses the computer s character set The significant differences are that while using the computer s LABEL statement is easier it also takes a lot more graphics memory than the internal char acter set This can become very important is you have several labels or want to have several hookup diagrams In this example only graphics page 1 is used You can inde pendently control up to 7 separate pages of graphics informa tion If you write too much information into one page it overflows into the next page When a graphics page is selected the the first location of memory that receives information identified by the pointer is reset to the beginning of the page Thus as information is written into the page the old information is destroyed 1f we were plotting a line this would appear as a new trace overwriting an old one Program 10 learning the instrument state Being able to save a specific instrument state is helpful when it is needed several times in a test or measurement procedure You can save the instrument state by manually logging the important analyzer and sweeper parameters such as start stop frequency sweep time number of trace points scale per division and display format then re input them at the ap propriate time A simpler approach
260. ess of plotting is slowed down when the buffer is on When the buffer is off all active functions are disabled and the plot is processed until finished NOTE The PLT BUF ON OFF softkey is preset at the factory in the ON position In order to speed up the plotting process turn this function off PRIOR MENU returns the previous menu SERVICE presents the service menu which provides a series of automated tests of the functional blocks of the analyzer These tests are described in section 8 of the service manual HP 8757C E Operating Reference 41 42 LOCAL LOCAL MENU HP 8757C 8757E INSTRUMENT STATE RECALL PRESET HP IB STATUS NI LOCAL il Figure 28 LOCAL Key and Local Menus The LOCAL key returns the analyzer to local operation from the remote operation state unless a LOCAL LOCKOUT command has been received over HP IB Pressing LOCAL also presents the local menu The local menu allows you to set HP IB addresses for the analyzer and other instruments connected to the 8757 system interface The default addresses for these instruments are shown in table 5 Table 5 HP IB Default Addresses 8757 Sweeper Piotter Printer Disk Drive 1 HP 8757C only Change the default addresses of these instruments by pressing the softkey for the instrument you wish to change For example press 8757 The current HP 1B address is displayed in the active entry area of the CRT Now en
261. ete flexibility when reading measurement traces via HP IB You can read from the active channel and you can read the stored memory trace the current measurement trace or the normalized trace meas urement minus memory In addition the memory trace can be written back to the analyzer allowing you to save and restore calibration traces via HP IB With trace transfer measurements some frequency resolu tion is sacrificed for measurement speed The number of points per trace can be programmed to control the resolution across the frequency range being swept If you are measuring a device that changes very rapidly with frequency it is possible to miss very narrowband responses that occur between measurement points if the resolution is low For these cases the measurement should be made at a higher resolution The trace transfer method of measurement is much faster than CW point by point measurements Program 6 listing 10 ASSIGN Sna TO 716 20 ASSIGN Fast_sna TO 716 FORMAT OFF 30 ABORT7 40 CLEAR Sna 50 OUTPUT G5na IP 60 DIM Ascii dat 0 400 70 INTEGER Bin dat 0 400 80 OUTPUT Sna CIA C2IB 90 WAIT1 100 OUTPUT Sna FD0 CIOD 110 ENTER Sna Ascii_dat 120 OUTPUT 5 CIWM Ascii dat 130 PAUSE 140 OUTPUT gGSna FD1 C20D 150 160 170 180 190 200 210 ENTER Fast_sna Bin_dat OUTPUT Sna USING K C2WM OUTPUT Fast_sna Bin_dat PAUSE FOR I 0 TO 400 Bin dat I I MOD 1
262. etec tors used The raster display provides high resolution for viewing measurements a I B7570 ONLY ee nmr Eight CRT attributes such as the grid the measurement traces for each channel and the labels i i are shown in various factory defined colors The hue saturation and color intensity are adjust ible for each of these CRT attributes f The analyzer is capable of driving both E dispi play and one external monitor simul aneously C Coi ior or ai monitors can be used provided that they are compatible with he analyzers scan rate and video levels te The analyzer can control external printers plotters and sources through the 8757 System Interface A printer and plotter buffer speeds measurements by returning control to the analyzer while data is printing 2 2 ed from external disks Four two in the HP 8757E independent but identical measurement channels allow simultaneous measurement and viewing of measurement parameters Three detector inputs A B and R accept AC or DC detected signals from detectors or bridges bapa se et le RE TED E HP 8757C ONLY Da ERR The Option 001 has four detector inputs A B C and R to process AC and DC detected signals ESP AANA AP ANNEANNE AAA AAAA A AAAA AAAA AEA AAAA EE EE RARE TI EE E EE MASAMI PATIL ARRAY SO
263. ettings Settings Saved on Disk 46 Remote Operation Converting Existing HP 8757A Software to the HP 8757C E Full Page Coordinates of the HP 8757C E Display 1 Quick Reference Guide for the HP 8757C E Scalar Network Analyzer Function Select Commands 8 iv HP 8757C E HPAB Only Functions 13 MOOGBS cct tdeo erae RE AE ees 15 CRT Graphics Commands 17 HP 8757C E Modified ASCII Character Set 19 HP 8757C E Status Byte Descriptions 20 Front Panel Keycodes mor 20 Aiphabetical Listing of HP 8757C E Programming CodeS 21 introductory Programming Guide for the HP 8757C E Scalar Network Analyzer with the HP 9000 Series 200 300 Desktop Computer BASIC HP 8757C E Status Byte Descriptions 11 Alphabetical Listing of HP 8757C E Programming Codes 22 Introductory Programming Guide for the 8757C E scalar network analyzer with the HP Vectra Personal Computer using Microsoft QuickBASIC 4 0 HP 8757C E Status Byte Descriptions 14 Alphabetical Listing of HP 8757C E Programming Codes E 24 IN CASE OF DIFFICULTY Summary Of Error Codes 2 Table of Contents Section 1 General Information CONTENTS 1 introduction 1 Analyzer Similarities 2 Manual Set Organization 3 Inst
264. evel Step size to d where dis for d dBm 0to60 dB for SWR 1t037 SWR for Volts 10V 1 HP 8757C Option 001 only C detector 8 Tablel Function Select Commands 2 of 6 HP IB Reference Set Reference Position q has a value from 0 to 8 corresponding to the Position major horizontal graticule lines 8 top graticule line 4 center graticule line 0 bottom graticule line Cursor Cursor on off Cursor Delta on off Cursor to maximum for the active channel Cursorto minimum for the active channel Set cursorsearch value to amplitude value of d d must bein therange of ratio measurement 60 to 60dB normalized measurement 60 to 60 dB power measurement 20to 60dBm Maximum resolution of dis 0 01 or dBm Cursor search functions are not allowed in SWR or Voltage display modes Cursor Search Left for the search value Cursor will search left to the first frequency point or interpolated point which equais the search value If the value cannot be found the message SEARCH VALUE NOT FOUND will appearin the ACTIVE ENTRY AREA Cursor Search Right for the search value Cursor will search right to the first frequency point or interpolated point which equals the search value If the value cannot be found the message SEARCH VALUE NOT FOUND will appear in the ACTIVE ENTRY AREA Cursor search for bandwidth representing the search value If the value cannot be found the message BANDWIDTH VALUE
265. evel functions to magnify the passband and making the ripple symmetrical about the reference line 12 SCALE Activates the scale function 0 2 dBm dB Sets scale to 0 2 dB division REF Accesses reference menu REF LEVEL Activates reference level function use the front panel knob to move the trace such that the ripple is symmetrical about the reference line read the average insertion loss in the active entry area of the display 2 MA A x T E gel i N een Ne D 0 i i STUP 1 7400 eee at STAT TO 24008Hz When finished reset the reference level to 0 dB for the following measurements 3 dB bandwidth On the HP 8757 bandwidth measurements are accom plished by selecting MAX CURSOR A ON OFF then moving the trace cursor to one side of the bandpass filter and locating the 3 dB point Determine the frequency at that point by turning CURSOR A ON OFF and noting the cur sor value Repeat the process to find the 3 dB point on the other side of the passband then manually compute the bandwidth The HP 8757C s cursor search functions allow the user to determine the 3 dB bandwidth with only a few keystrokes SCALE Activates scale function AUTOSCALE Scales traces CURSOR Turns cursor on activates menu SEARCH Activates search menu displays current search value default value equals 3 dB BANDWIDT
266. evice Before gaging any precision 7mm connector therefore consult the mechanical specifications provided with the connector or the device itself Cleaning Precision 7mm Connectors Cleaning is discussed in detail in Part One of this Microwave Connector Care Manual which should be consulted for further information Whenever the center conductor collet has been removed from a precision 7mm connector the interior surfaces should be inspected carefully and if necessary cleaned The most suitable method is to cut off the sharp tip of a round wooden toothpick and to wrap it with a single layer of lint free cleaning cloth Moisten the cloth with a small amount of cleaning solvent and carefully insert it into the connec tor to clean the interior surfaces Use an illuminated magnifying glass or microscope to see clearly the areas you wish to clean With the center conductor collet in place the easiest and best way to clean precision 7mm connectors on small components cables and calibration or verification standards is to put a lint free cleaning cloth flat on a table and put a drop or two of cleaning solvent in the center of the cloth Retract the connector sleeve threads so that the connector interface is exposed Then gently press the contact end of the connector into the cloth moistened with solvent and turn it Blow the connector dry with a gentle stream of compressed air This method can be adapted for fixed connectors such as those attached
267. ey menus together 2 Locate the softkey on the map then note which front panel key presents the softkey menu containing this softkey 3 Locate the associated front panel key in Contents on the front page of this section 4 Turn to the page number listed HP 8757C E Operating Reference Operating Reference FRONT PANEL FEATURES C3 E3 C3 9 a OUE EE s 68 03 CJ CJ GJ INSTRUMENT STATE Riemer ge 2 s a i eene Beal STATUS 8757C SCALAR NETWORK ANALYZER 2 HSWLETT PACKANS Figure 1 The HP 8757C Option 001 Front Panel CRT This screen shows measurement annotation soft key labels data traces and other informa tion See figure 2 for CRT details CHANNEL These keys select the active channel FUNCTION These keys engage functions such as calibration and averaging They present softkey menus that generally apply to the active channel only ENTRY The entry area includes the knob the STEP keys and the numeric keypad These are used for entering data INSTRUMENT STATE These keys are used to control system functions such as plotting and defining titles that apply to the entire instrument state not just to a single channel DETECTOR INPUTS These connectors are used for connection of compatible detectors and directional bridges SOFTKEYS The softkeys are used to present functions in the menus and for instrument status information
268. f and on To use the graphics off on capability of the HP 8757 change BL5 in line 90 of program 9 to BLA and make the necessary changes in the size of the background grid These and other changes are illustrated in the following listing The same principle can be used to save anything stored to disk on the HP 8757C in the first seven pages of user graphics By having the softkeys available the user can store CRT graphics onto a disk for later recall Program 11 listing 10 REM INCLUDE 20 CLS ISC amp 7 Sna amp 716 50 Passthru 717 CALL IOTIMEQUTCISC amp 1013 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 70 CALL IOGABORTCISC amp IF PCIB ERR NOERR THEN ERRDR PCIB BASERR QBSETUP 80 CALL IOCLEARCISC amp IF PCIB ERR NOERR THEN ERROR PCIB BASERR 90 A IP BLA PT15 GOSUB IOQUTS 100 A EP GP1 1 DEC GOSUB IOQUTSP 110 A SP 6 GOSUB 000 5 120 FOR Col 0 TO 25 130 AS PU STRSCCol 1002 0 PD PA STR CCol 100 2000 GOSUB IOOGUTSP 140 NEXT Col 150 FOR Row 0 TO 20 160 A PU PA 0 STRSCRow 100 PD PA 2500 STR CRow 100 GOSUB IQOUTSP 170 NEXT Row 180 A SP 8 GOSUB 000 5 190 A PU 600 1600 PD GOSUB IODUTSP 200 A SI0 28 0 34 LBCONNECTION DIAGRAM CHR C32 GOSUB IQOUTSP A PU PA 1200 250 PD GOSUB IOQUTSP A S10 28 0 34 LBDUT CHR C32 GOSUB IQOUTSP AS PA 300 800 P
269. f the CRT turn it on by pressing SYSTEM MORE SWEEP MODE SYSINTF ON On the analyzer press PRESET to preset both the analyzer and the source At preset the analyzer channel 1 is active and measures input A Adjust the start and stop frequencies of the source to include the frequency range of the microwave test device These frequencies will be plotted with the data for a permanent record Turn off the analyzer s channel 2 Press CHANNEL 2 CHAN 2 OFF For the HP 8757E press CHANNEL 2 twice On the analyzer press CURSOR MAX to place the cursor at the maximum value of the trace The CRSR value is displayed in the active entry area of the CRT Adjust the output power of the RF plug in until the cursor value on the CRT reads 16 dBm This value is the upper limit of the dynamic range of the analyzer Press DISPLAY MEAS MEM to store the trace in memory The message CHAN 1 MEAS TO MEMORY will be shown on the message line of the CRT Disconnect the detector from the RF output of the source Press AVG AVG ON OFF to turn on averaging with the default average factor of 8 Wait a few seconds to allow the trace to settle Press CURSOR MAX A cursor value of 60 dBm or lower should be displayed in the active entry area This is the noise floor power level Insert the microwave test device between the RF output of the source and the detector On the analyzer press DISPLAY MEAS MEM Wait a few
270. f the analyzer SERIAL NUMBER PE PREFIX SUFFIX SER 1234A 12345 FACTORY INSTALLED options OPT 000 o 2 7 HEWLETT PACKARD MADE iN USA Figure 1 2 Typical Serial Number Plate Other analyzers differ from those covered directly by this manual Those differences are documented in the Manual Backdating section of this manual The title pages of both manuals show a microfiche part number This number can be usedto order 10 by 15 centimeter 4 by 6 inch microfilm transparencies of the manual set SAFETY CONSIDERATIONS This product has been manufactured and tested in accordance with international safety standards Before operation review this product and related documentation for familiarity with safety markings and instructions A complete listing of safety considerations is provided at the end of this section and also in the service manual SPECIFICATIONS Instrument specifications are listed in table 1 1 These specifications are the performance standards against which the analyzer is tested Table 1 2 lists supplemental performance characteristics These are not specifications but indicate typical non warranted performance parameters of the instrument HP 8757C E Generai Information 1 3 ANALYZER DESCRIPTION The HP 8757C E is a microprocessor based receiver capable of making scalar magnitude only reflection and transmission measurements The frequency range is determined by the external d
271. faces If galling is evident replace the connector nut assembly This can generally be done without any degradation of connection repeatability or measured data because the connector interface is not disturbed If the interior bearing surfaces are undamaged a small amount of molybdenum disulfide lubricant can be applied provided that great care is taken to avoid getting any lubricant on the mating plane surfaces or the connector threads Lubricant on the connector nut threads tends to collect dirt and thus counteract the benefits of the lubricant Making Connections 29 30 e Disconnection Disconnect connectors by grasping the device body firmly to prevent it from turning Then loosen the connector nut that was tightened in order to make the connection If necessary use the torque wrench or an open end wrench to start the process but leave the connection finger tight At all times support the devices and the connection to avoid putting lateral bending force on the connector mating plane surfaces Complete the disconnection by disconnecting the connector nut completely As in making connec tions turn only the connector nut Never disconnect connectors by twisting one connector or device out of the other as one might remove a screw or a light bulb This is extremely harmful and can occur whenever the device body rather than the connector nut alone is turned If the connection is between sexed connectors pull the connectors straig
272. faster and easier Under HP IB 210 IF Keycode lt gt 41 THEN GOTO Wait srq control you can re label the softkeys with any annotation 220 PEN OFF and sense when they are pressed 230 END 240 Srq recv Use the softkeys to branch to special measurement 250 CALL IOSPOLL Sna amp Intr bit grams By making full use of the softkeys your automatic IF PCIB ERR lt gt NOERR THEN ERROR system may not need a normal computer keyboard at all PCIB BASERR making it as easy to use as a manual instrument 260 A OK GOSUB 1000 5 m 270 CALL IOGENTERCSna amp Keycode Program 8 listing 280 SELECT CASE Keycode CASE 32 10 REM INCLUDE QBSETUP 290 CLS LOCATE 12 29 PRINT Calibration 1 20 CLS 300 CASE 8 30 Isc amp 7 310 CLS LOCATE 12 29 PRINT Test 1 40 Snak 716 320 CASE 0 50 CALL IOTIMEQUTCIsc amp 1012 330 CLS LOCATE 12 29 PRINT Calibration 2 IF PCIB ERR lt gt NOERR THEN ERROR 340 CASE 16 PCIB BASERR 350 CLS LOCATE 12 29 PRINT Test 2 60 CALL IOABORTCIsc amp 360 CASE 41 IF PCIB ERR lt gt NOERR THEN ERROR 370 CLS LOCATE 12 29 PRINT Abort PCIB BASERR 380 CASE ELSE 70 CALL IGCLEARCIsca 390 CLS LOCATE 12 29 PRINT IF PCIB ERR NOERR THEN ERROR Undefined PCIB BASERR 400 END SELECT 80 PEN OFF 410 RETURN 90 A IP GOSUB IOQUTS 420 IOQUTS CALL IOQUTPUTSCSna amp A LENCA 100 A CS GOSUB IODUTS 430 IF PCIB ERR lt gt NOERR THEN ERROR 110 A
273. for detector B External detector cal value for detector C External detector cal value for detector R 1 HP 8757C only NOTES n decimalinteger 1 to 9 2 HP 8757C Option 001 oniy detector C d variable length numeric 3 Limitline functions vatid oniy for channels 1 or 2 HP 8757C only m 0 foroff i foren 4 Revision 3 1 or above for an HP 8757 q unique value s ASCli or binary string 25 For more information call your local HP sales office listed in your telephone directory or an HP regional office listed below for the location of your nearest sales office United States Hewlett Packard Company 4 Choke Cherry Road Rockville MD 20850 301 670 4300 Hewlett Packard Company 5201 Toliview Drive Roiling Meadows IL 60008 312 255 9800 Hewlett Packard Company 5161 Lankershim Blvd No Hollywood CA 91601 818 505 5600 Hewlett Packard Company 2015 South Park Place Atlanta GA 30339 404 955 1500 Canada Hewlett Packard Ltd 6877 Goreway Drive Mississauga Ontario L4V1M8 416 678 9430 aso Australia New Zealand Hewlett Packard Australia Ltd 31 41 Joseph Street Blackburn Victoria 3130 Melbourne Australia 03 895 2895 Europe A frica Middle East Hewlett Packard S A Central Mailing Department P O Box 529 1180 AM Amstelveen The Netherlands 31 20 547 9999 Far East Hewlett Packard Asia Ltd 22 F Bond Centre West Tower 89 Queensway
274. frequency GHz Start freq INPUT Stop frequency GHz Stop freq OUTPUT qPassthru FA Start freg GZ FB Stop freg GZ OUTPUT Sna END 160 170 180 190 200 Program 3 explanation Line 10 Direct the printed output to the computer CRT Line20 Assign an I O path to the address of the analyzer This is the analyzer s control address Line30 Assign an I O path to the analyzer s passthru address By communicating to this HP IB address the computer will control a device connected to the 8757 SYSTEM INTERFACE Line40 Abort any transfers and clear the HP IB interface of the computer Line50 Clear the HP IB interface of the analyzer Line 60 Preset analyzer and source Line 70 the analyzer which device is controlled through the analyzer s passthru address In this case the source device 19 Line 80 Send a command to the source Command it to output its current start frequency Line 90 Read the start frequency from the source Line 100 Scale the start frequency to display it in GHz Line 110 Command the source to output its current stop frequency Line120 Read the stop frequency from the source Line 130 Scale the stop frequency to display it in GHz Line 140 Exit passthru mode by addressing the analyzer Line 150 Printthe start and stop frequency Line 160 Get the start frequency from the user Line 170 Get the stop frequency from the user Line 180 Set the start and stop frequency of the
275. g manual Note Remote operation of the HP 8757C E applies to operation with the HP Interface Bus HP IB connector on the rear panel of the analyzer Do not connect an HP IB controller to the 8757 SYSTEM INTERFACE connector HP IB control of the instruments connected to this port is described in the Passthrough portion of this document HP IB capabilities The following codes describe the HP IB electrical capabili ties of the HP 8757C E using IEEE Std 488 1978 mne monics HP IB GP IB IEEE 488 and IEC 625 are all electrically equivalent The mnemonics briefly translate as follows SH1 Source Handshake complete capability Acceptor Handshake complete capability T6 Talker capable of basic talker serial poll and unaddress if MLA Talker Extended address no capability L4 Listener capable of basic listener and unaddress if MTA LEO Listener Extended address no capability SR1 Service Request complete capability RL1 Remote Local complete capability PPO Parallel Poll no capability DC1 Device Clear complete capability Device Trigger no capability CO Controller no capability El Electrical specification indicating open collector outputs These codes are completely explained in the IEEE Std 488 1978 document published by the Institute of Electrical and Electronic Engineers Inc 345 East 47th Street New York New York 11017 uam See Input data
276. g measurements with the analyzer This function is on at preset and power on Turn off temperature compensation only when diagnosing a possible problem with the analyzer or its detectors 26 Operating Reference HP 8757C E SPCL SPECIAL MENUS FUNCTION DISPLAY AVG HP 8757C HP 8757 Figure 16 SPCL Key and Special Menus The SPCL key presents the special functions menu SMOOTH ON OFF toggles the smoothing function on and off Smoothing video filtering calculates a moving average of the active channel data The aperture of the moving average is a percent of the sweep span not greater than 20 Smoothing is different from averaging Averaging computes each data point based on the average value of each point during several sweeps Smoothing computes each data point based on one sweep on the average of data points on both sides of that data point in the current sweep An S is shown the status symbols area of the mode labels for any channel that has smoothing activated Smoothing is off for channels at preset SMOOTH APERT iets you change the value of the smoothing aperture The aperture defaults to 596 at preset Use the knob STEP keys or numeric keypad to change the smoothing aperture value Enter any value from 0 1 through 20 HP 8757C E Operating Reference 27 ENTER LIM LNS presents the first of two limit lines menus Using these softkeys you can define limit lines f
277. g statements built into the computer such as MOVE DRAW PEN AXES VIEWPORT etc This program draws a connections diagram for a hypotheti cal test system measuring an amplifier It will blank the analyzer s standard display containing the graticule annotation and softkeys so that we have a blank CRT Figure 2 shows what the CRT should look like when the program is done Since the program involves drawing many lines it will use the BASIC data statement to more efficiently store where to draw lines For fast easy to use graphics the graphics memory of the HP 8757C E is divided into seven pages of 500 words and an eighth page of 4000 words One vector requires two words Each of the pages may be selected to receive data and be turned on and off independently You can keep different drawings in each of the graphics memory pages and simply turn on the drawing you need by turning on the appropriate page Each page may also be erased independently To use the graphics capability of the HP 8757C E first define the passthru address to be one digit less than the analyzer s control address If the analyzer s address is 16 its graphics address is 15 To the computer the CRT of the analyzer looks like a plotter connected to the 8757 SYSTEM INTERFACE CONNECTION DIAGRAM Figure2 The CRT Graphics Display 14 Program 9 listing 10 i 50 300 ASSIGN Sna TO 716 20 ASSIGN Passthru TO 717 30 ABORT 7 CLEAR 5Sna OU
278. g them suitable for many connections and disconnec tions For this reason they are widely used in test and measurement applications requiring a high degree of accuracy and repeatability They are generally made of beryllium copper alloy plated with gold Precision 7mm connectors are generally designed for use as sexless connectors able to mate with all other precision 7mm connectors There is no male or female and contact between the center conduc tors is made by replaceable inserts called collets designed to make spring loaded butt contact when the connection is tightened Small mechanical differences do sometimes exist between precision 7mm connectors made by differ ent manufacturers and occasionally these differences can cause difficulty in making connections Always inspect all connectors mechanically using a precision connector gage to make sure that they meet their critical specifications Precision 7mm Connectors 31 32 MECHANICAL SPECIFICATIONS OF PRECISION 7mm CONNECTORS e With the center conductor collet removed no protrusion of the center conductor in front of the outer conductor mating plane is ever allowable and sometimes a minimum recession is required Consult the mechanical specifications provided with the connector or the device itself The center conductor collet should spring back immediately when pressed with a blunt plastic rod or with the rounded plastic handle of the collet removing tool in precision
279. ge selector PC board Posi tion PC board so that voltage nearest actual line voltage level will appear in module window Push board back into its slot 3 Push fuse pull lever into its normal right hand position 4 Check fuse to make sure it is of correct rating and type for input ac line voltage 5 Insert correct fuse in fuseholder Operating voltage appears in module window Figure 2 1 Power Line Module Power Cable The analyzer is equipped with a three wire power cable in accordance with international safety standards When connected to an appropriate outlet this cable grounds the instrument cabinet Table 2 2 shows the styles of plugs available on power cables supplied with instruments Each HP part number in column two refers to a complete power cable including the plug illustrated in column one The type of power cable shipped with the instrument depends on the country of destination WARNING Before turning on line power to the analyzer ensure that only the spec ified power cord is used Insert the power cord only in a socket outlet provided with a protective earth contact The offset pin of the three prong connector is the grounding pin The analyzer can safely be operated from a two contact outiet only when using a three prong to two prong adapter and connecting the green wire of the adapter to ground Do not negate these protective features by using an extension cord without a protective ground conductor or by g
280. ged e 9 9 9 The following analyzer conditions are not changed during a PRESET or IP command execution Reference position Trace memory Save recail registers HP IB addresses Request mask Limit lines Title Detector offset User defined plot Repeat autozero timer Display intensity Display colors 1 HP 8757C only HP 8757C E 8757 system interface private bus control on off Operating Reference 91 HP IB STATUS R LE S e e e e HP IB STATUS Figure 27 HP IB STATUS Indicators The HP IB STATUS indicators figure 27 show the current status of the analyzer When the indicator is lit the analyzer is in the status represented by the indicator Indicator Analyzer Status R Remote operation L Listen mode T Talk mode S Service request SRQ asserted The indicators are not updated continuously it is possible for several complete HP IB operations to take place without any change in status 52 Operating Reference HP 8757C E Detector inputs Figure 28 Detector Inputs Figure 28 shows the analyzer s detector inputs Each input has identical characteristics and allows connection of compatible detectors and bridges Input A is typically used for the connection of a directional bridge for reflection measurements Input B is typically used for the connection of a detector for transmission measurements pM M E BTBTC ONLY input Option 001 only is an optional channel
281. gh A6 assemblies Two 5 V test points and two digital ground test points are provided for powering digital troubleshooting devices logic probe logic pulser current tracer Extension cables to provide easier access while troubleshooting the A15 display and the A14 display interface HP8757C E General Information EQUIPMENT REQUIRED BUT NOT SUPPLIED A swept RF or microwave source and from one to three detectors or directional bridges are required to make measurements with your standard analyzer Four detectors or bridges can be used with the Option 001 POIVRE EE E a eg Eee E E ONE For AC detection measurements square wave modulation capability at 27 778 kHz is required internally or through the use of an external modulator The data sheet for the HP 8757C E describes typical equipment setups and lists equipment available For further information contact your local Hewlett Packard office RECOMMENDED TEST EQUIPMENT Equipment required to test and service your analyzer is listed in table 4 1 of this manual Other equipment may be substituted if it meets or exceeds the critical specifications listed in the table HP 8757C E General Information 1 7 Table 1 1 Specifications and General Requirements 1 of 2 HP 8757C E SPECIFICATIONS Specifications describe the instrument s warranted performance over the temperature range of O to 55 C 32 to 131 F except where noted Fun
282. h varies in frequency SWR An abbreviation for Standing Wave Ratio calculated as 1 p 1 p Sync An abbreviated term for synchronization Termination A load connected to a transmission line or other device Terminator A keystroke or code if programming that indicates the end of a numeric entry Thru An abbreviation for through which is used to refer to a calibration technique Tint A shade of a color hue Toggle To switch states usually to change a function from on to off or off to on Transmission The measurement of the insertion loss or gain of a network or device Transparent Something that is not visible to the user Usually a procedure that occurs without the user s initiation or knowledge Variable A symbol the numeric value of which changes from one iteration of a program to the next or within each iteration of a program Vector 1 A quantity that has both magnitude and phase 2 A network analyzer capable of measuring both magnitude and phase Vertical Resolution The degree to which an instrument can differentiate between 2 closely spaced signal amplitudes HP 8757C E Glossary A A SOKOV osuere e eR re 11 AJB softkey 11 AIC softkey 11 AIR softkey 11 abort s 35 eri PP EE 98 programming message QRG 7 ABORT PLOT softkey 35 ABORT PRINT softkey 38 absolute power accuracy
283. hanically using a connector gage How often connectors should be gaged after that depends upon usage In general connectors should be gaged whenever visual inspection or electrical performance sug gests that the connector interface may be out of specification for example due to wear or damage Connectors on calibration and verification devices should also be gaged whenever they have been used by someone else or on another system or piece of equipment Precision 3 6mm SMA connectors should be gaged relatively more often than other connectors owing to the ease with which the center pins can be pulled out of specification during disconnection Connectors should also be gaged as a matter of routine after every 100 connections and disconnec tions initially more or less often after that as experience suggests Mechanical Specifications The critical dimension to be measured regardless of connector type is the position generally the recession or setback of the center conductor relative to the outer conductor mating plane See Figures 6 through 9 Mechanical specifications for connectors specify a maximum distance and a minimum distance that the center conductor can be positioned behind or in female Type N connectors in front of the outer conductor mating plane Nominal specifications for each connector type exist But the allowable tolerances and sometimes the dimensions themselves differ from manufacturer to manufacturer and fr
284. he color list will not accommodate special circumstances such as color deficient vision additional adjustments can be made The most frequently occurring color deficiency is the inability to distinguish red yellow and green from one another Confusion between these colors can usually be eliminated by increasing the brightness between the colors if additional adjustment is needed vary the degree of whiteness of the color Usually only minor changes are needed Color is composed of three parameters Color Brightness A measure of the brightness of the color Color The degree of whiteness of the color A scale from white to pure color Tint The continuum of hues on the color wheel ranging from red through green and blue and back to red Three softkeys allow you to adjust the color brightness color and tint of any CRT attribute Press the softkey for the attribute Now press MODIFY COLOR and choose any of the adjustments COLOR BRTNESS changes the attribute s color brightness Press this softkey and the existing value set for the attribute is shown on the CHT Use the front panel knob or numeric keypad to enter a new value for color brightness Observe the attribute on the CRT It changes as you change values Terminate your keypad entry with the ENT key when your adjustment is complete COLOR changes the degree of whiteness of the color of the attribute This parameter is adjusted the same way as COLOR BRTNESS TI
285. he other connector are unusually tight A male SMA connector pin that is bent or is too long may smash or break the delicate fingers on the female connector especially if it is a precision 3 5mm connector Very often too SMA male pins are actually not pins at all but the cut off ends of the center conductor in ordinary semi rigid coaxial cable Misalignment and burrs are common in this situation and burrs on the end of the male pin can ruin any female SMA or precision 3 5mm connector that they are mated to inspect all male SMA connectors for misalignment or burrs on the male contact pin and discard any that are damaged SMA and Precision 3 5mm Connectors SMA CONNECTORS OUTER CONDUCTOR EN EU DTE EGTA ic gt ISS CENTER acm CONDUCTOR OUTER CONDUCTOR MATING PLANE FEMALE OUTER CONDUCTOR EZA pieveerals NY CONDUCTOR Y OUTER CONDUCTOR MATING PLANE Figure 21 SMA Connectors SMA and Precision 3 5mm Connectors 55 56 Precision 3 5mm Connectors Precision 3 5mm connectors also known as APC 3 5 connectors were developed during the early 1970 s jointly by Hewlett Packard and Amphenol Corporation The design objective was to produce a durable high frequency microwave connector that would mate with SMA connectors exhibit iow SWR and insertion loss and be mode free up to about 34 GHz Unlike SMA connectors precision 3 5mm connectors are air dielectric devices Figure 22 Air i
286. hown in figure 2 7 are available for recording instrument HP IB addresses See Replaceable Parts in the service manual for ordering information E p HP Part No 7120 5855 Figure 2 7 HP IB Address Label OPERATING ENVIRONMENT To ensure that no damage to the analyzer occurs operate the analyzer only under the following conditions Analyzer specifications are warranted for these conditions except where noted in table 1 1 Specifications and General Requirements Temperature 0 to 55 C 32 to 131 Relative Humidity 15 to 95 at 25 to 40 C 77 to 104 Protect the analyzer from temperature extremes that could cause condensation within the instrument Altitude Up to 4 572 m 15 000 ft Cooling Clearance for ventilation should be atleast 10 cm 4 in at the rear of the cabinet and 7 6 cm 3 in at the sides The clearances provided by the plastic feet in bench stacking and filler strips in rack mounting are adequate for the top and bottom cabinet surfaces The fan mounted in the rear of the analyzer moves air into the instrument and out through the sides Ensure that the air intake and exhaust clearances are met and that the fan filter is cleaned regularly HP 8757C Installation 2 13 2 14 STORAGE AND SHIPMENT ENVIRONMENT The analyzer can be stored or shipped in environments within the following limits Temperature 40 to 70 C 40 to 167 Relative Humidi
287. ht apart and be especially careful not to twist the body of any device as you do so Twisting the connection can damage the connector by damaging the center conductors or the interior component parts to which the connectors themselves are attached It can also scrape the plating off of the male contact pin or even in rare instances unscrew the male or female contact pin slightly from its interior mounting bringing it out of specification This can also occur if the female contact fingers are unusually tight if such a male pin is then inserted into a female connector it will damage the femaie connector by pushing its center conductor back too far Be aware of this possibility and measure the center conduc tor recession of ail such connectors before mating them again Making Connections Precision 7mm Connectors Precision 7mm connectors among them APC 7 connectors are used in the dc to 18 GHz range and offer the lowest SWR and the most repeatable connections of any 7mm connector type Development of these connectors was begun by Hewlett Packard in the mid 1960 s and improved upon by Amphenol Corporation now one of the principal manufacturers of the connector APC 7 is a U S registered trademark of the Bunker Ramo Corporation Precision 7mm connectors Figure 13 are air dielectric devices The center conductor is supported only by a plastic support bead inside the connector body Precision 7mm connectors are durable makin
288. i REMOTE OPERATION Converting Existing HP 8757A Software to the HEBIBICIE uu Aone Mee ey Coa CIEL 1 Quick Reference Guide for the HP 8757C E Scalar Network Analyzer itroun ERE RET bee SEIS EPOR 1 HP IB Capabilities 1 Input Data NODI Rd Pics ee Leas 2 SYNE Hee ea oes nt adr diat 2 Valid Chataclel Seu oi oE 3 Programming Data 3 Instrument Preset 3 Passthroigli cedex ioe ba EN ee eda CY Re ge Ra 4 8757 System Interface 4 CRT Graphies xp Lose ua erae ee Pes dra bord 5 OUIDUI Dala i rss erg weed S Y e Ra 5 Learn SIAR Sek eo 5 Interrogate Function 5 CPI MM DF P 5 Eror ven aha aer y Eua ati C ee de a SONS 5 Data exu eee clus ep re dx RP nen nad CP US 6 Identity oC ess at hak eee ae ata Med RET Res 6 UP EET 6 eL cr 6 PemotelLo6cal bosco ve cus rou TEQUE 6 Service Heguast iusso IEEE Value Res 6 Status Byl o0 scie x ata 6 Status Bit CANI X Ep MEE fe ee 6 Controller Capabilities 6 WOON san coa ee hears 6 Self test 7 Address Assignment Information h Secure Frequency Mode 7 introductory Programming Gu
289. icator dial indicates that the shoulder of the male contact pin is recessed less than the minimum reces sion of 0 207 inches behind the outer conductor mating plane Such a connector is out of specifica tion It will damage other connectors to which it is mated and should not be used Type N Connectors 49 MALE TYPE N CONNECTORS Attach male bushing to dial indicator assembly TWO ALLEN SCREWS GAGE PLUNGER ASSEMBLY DIAL LOCK SCREW 0 210in COUNTER CLOCKWISE DEFLECTION Insert gage into connector Ses RP AZAR Rs Spd Ls 0 207in Figure 20 Gaging Type N Connectors 1 of 2 50 Type N Connectors FEMALE TYPE N CONNECTORS Attach female bushing to dial indicator assembly TWO ALLEN SCREWS GAGE PLUNGER ASSEMBLY DIAL LOCK SCREW 0 204in COUNTER CLOCKWISE DEFLECTION 0 207in Figure 20 Gaging Type N Connectors 2 of 2 Type N Connectors 51 52 Female Type N Connectors To gage female Type N connectors Figure 20 first attach the bushing for female connectors to the dial indicator assembly This bushing has a protruding circular sleeve and when the bushing has been attached to the dial indicator assembly the gage plunger will be inside this circular sleeve The bushing is fastened to the gage plunger assembly using the two Allen screws in the bushing Zero the gage using the protruding end of the gage calibration block insert
290. ide for the HP 8757C E scalar Network Analyzer with the HP 9000 Series 200999 Desktop Computer BASIC INWOCUCHOR r oed uRETER AED tes EAD Reeds 1 Reference Information aha Se us 1 Equipment Required 2 c dr 22 nte a 3 Check Out Procedure 3 Programming Examples 3 Program 1 Remote Local and Local Lockout 3 Program 2 Controlling the Front Panel 5 Program 3 Passthru Mode 6 Program 4 Cursor Operations 7 Program 5 Read a Single Value 8 Program 6 Trace Transfer 9 Program 7 Using the TAKE SWEEP Command 11 Program 8 Programming the Softkeys 13 Program 9 CRT Graphics ursa Meee os 14 Program 10 Learning the instrument State 16 Program 11 CRT graphics on the HP 8757C 18 Program 12 reading disks from the HP 8757C 19 ii HP 8757C E Introductory Programming Guide for the HP 8757C E scalar network analyzer with the HP Vectra Personal Computer using Microsoft QuickBASIC 4 0 Inirodu tion RD EET 1 Reference information 1 Equipment Required 1 DOUUD E oa ome a E EEA Ka 2 Check Out Procedure 2 Programming Examples awe Program 1 Remote Local and Local Lockout
291. ides access to 7 default col ors white black yellow blue salmon red and green All the color selection menus are accessed via the ADJUST DISPLAY softkey in the DISPLAY menu as shown in the following layout of the color menus HP 8757C DISPLAY 24 If the modification of the default colors is necessary the user may select the MODIFY COLOR softkey at the bottom of the color list menu It allows the user to change the color of a particular item e g channel 1 by adjusting the tint color and or brightness In monochrome mode the active trace is displayed with greater intensity then other traces Once in monochrome mode select ADJUST DISPLAY then DEFAULT COLORS to reactivate the color mode Frequency blanking The frequency blanking function in conjunction with the 8757 System Interface allows the user to operate the ana lyzer in a secure mode by deleting all frequency annotation on the analyzer and the source Once the FRQ LBL OFF softkey has been selected from the SYSTEM menu fre quency annotation may not be reactivated until the instrument is preset Storing information in the internal reg isters or on an external disk with frequency blanking enabled guarantees that frequency blanking will stili be active when it is retrieved even if the analyzer was preset prior to the recall operation The following sequence acti vates the frequency blanking function SYSTEM Accesses system menu LABE
292. ight be mated It is much easier and much cheaper to replace an adapter than it is to repair or replace test equipment In all instances the new interface will have the connector type listed in Figure 17 For example using a male precision 3 5mm SMA compatible adapter HP Part Number 1250 1746 will result in a male precision 3 5mm interface to which devices or cables with female 3 5mm or SMA connectors can be connected In most applications two adapters will be required one each at the input and the output of the device Adapters are included in many HP calibration kits or may be ordered separately using the part numbers given in Figure 17 SMA Compatible Adapters for HP 85021 27 series Directional Bridges When devices with SMA connectors are to be measured at frequencies from 10 MHz to 18 GHz using an HP 85021 27 series directional bridge Hewlett Packard recommends using the HP 85021 27A 7mm directional bridge and 7mm to 3 5mm adapters If a slight loss in directivity can be tolerated this arrangement is much better than using the HP 85021 27B 3 5mm directional bridge and connecting the SMA devices directly to it It is much easier and much cheaper to replace a male or female 3 5mm to 7mm adapter than it is to repair a bridge HP 85130A Special Adapter Kit In order to produce a 7mm interface on the 3 5mm test ports of the HP 8513A and HP 8515A test sets for example to use 7mm calibration or verification devices or the HP 85041A t
293. ilable that are not found on the HP 8757E These commands are handled in the same manner as an unknown command An unrecognized command will simply be disregarded by the HP 8757E However with each occurrence of an unknown command the analyzer will stop and display a message on the CRT before continu ing on to the next command The message will be displayed for about 2 seconds to make the user aware that the analyzer had received an unknown command HP 8757C E Remote Operation Softkey Locations If an existing program bases any part of its operation on the menu structure softkey placement of the HP 8757A then the program must be updated to reflect the new menu structure in the HP 8757C E Learn Strings There should be no difficulties in using the learn string from the HP 8757A on the HP 8757C E Preset Timeout Allow a minimum of 20 seconds after an instrument preset on the HP 8757C E for internal diagnostics to be completed Remote Operation HP 8757C E HP IB Programming Note Quick Reference Guide EA Packar For the HP 8757C E Scalar Network Analyzer Introduction This programming note is a reference guide for the remote operation of the HP 8757C E Scalar Network Analyzer with firmware revision 3 0 or greater This note is intended for use by those familiar with HP IB programming and the basic functions of the HP 8757C E For operation informa tion for the analyzer refer to the Operating Reference in the operatin
294. ill be cleared erasing any data A segment may not be modified mistakes may only be corrected if the units i e GHz or dB for that particular entry have not been selected yet then the BK SP backspace key may be utilized to erase the entry To delete segments select DELETE SEGMENT or DELETE ALL LNS from the limit line menu Creating limit lines for a bandpass filter Preset Connections Connect DUT as for insertion loss measurement Controls Measurement CHAN 2 OFF j MEAS B R Source parameters CF 10 24 GHz AF 2 GHz POWER LEVEL 10 dBm dB Calibrate Perform thru calibration Save After the limit lines have been created the setup should be saved again Measure Adjust trace for best data presentation SPCL LIM LNS ON OFF ENTER LIM LNS ELAT LIMIT 8 24 GHz 55 dBm dB ENT 9 6 GHz SLOPE LIMIT The following table supplies the entries necessary to create the limit lines shown in the figure Seg Type Upper Lower Freq Upper Lower dB dB GHz dB dB FL SL 1 95 Enters the first segment from the table below U gt W m 4 MA Available only on the HP 8757C To deactivate a channel on the HP 8757E press it s hardkey until the channel turns off 20 Alternate sweep The alternate sweep function of the HP 8350B sweep oscillator and HP 8340B 8341B synthesized sweepers was designed for us
295. ing SWP DAC MIN The difference between this value and the value noted in step 3 should be 10 2375 0 0005 VDC If not adjust A4R6 DAC ADJ to bring the difference within specification 5 Repeat steps 3 and 4 until this difference is attained MAIN ERROR CODES Error Codes 15 through 13 Failure All of these codes are associated with the A3 CPU board Replacement of the A3 board will restore operation Equipment Required HP 11613A B Error Code 12 Failure One or more of the power supplies have failed First check all fuses Remove boards one at a time except the A3 CPU board and cycle the power each time to check for board shorts If none of these solve the problem replace the A12 power supply board Equipment required DVM if the A12 is replaced Error Code 11 Failure The A3 CPU cannot communicate with the A6 board via the instrument bus Either the A3 the A6 orthe motherboard could be bad Since the bus also goes to other boards remove the A2 A4 and A14 boards to eliminate the possibility of shorts on these boards Verify that the same failure occurs If it does replace ail the boards that were removed remove the A6 board and close switch A3S1 D This will bypass all self tests If the instrument then seems to perform normally locally the problem is with the A6 board if it does not perform normally the problem is with the A3 board Equipment required HP 11613A B if the A3 is replaced Error Co
296. ing and or single point limit lines on the HP 8757C s display Limit lines are defined in terms of upper and lower specifications for a particular frequency or band of frequencies When combined these lines represent the per formance constraints of the device under test Up to 12 limit segments are available for channels 1 and 2 for traces with 401 points or fewer They may be stored in the analyzer s internal save recall registers 1 through 4 The following sequences will describe how to create each type of limit line and the sequence for the measurement of the passband filter previously shown Accessing the limit menu SPCL Accesses the special functions menu LIM LNS ONOFF Turns on the limit line function ENTER LIM LNS Accesses the limit line menu Creating flat limit lines ELAT LIMIT Sets up the flat limit function 10 1 GHz Enters start frequency for first segment 1 dBm dB Enters upper limit 2 dBm dB Enters lower limit 10 3 GHz Enters stop frequency Flat limit lines are useful for testing insertion loss and passband ripple The limit lines of the first segment should be displayed as soon as the stop frequency is entered Once the first segment has been entered the user may choose to start another segment by selecting the limit line type or terminate the limit line selection process by selecting DONE the SPCL menu will reappear Creating sloped limit lines
297. ing measured Hold the gage by the plunger barrel not the dial housing or cap and for male connectors slip the protruding end of the calibration block into the circular bushing on the connector gage For precision 7mm connectors and female precision 3 5mm connectors use the flat end of the gage calibration block For female Type N connectors use the recessed end of the gage calibration block Hold the gage by the plunger barrel only Figure 10 Doing so will prevent errors in gage readings due to the application of stresses to the gage plunger mechanism through the dial indicator housing Carefully bring the gage and gage block together applying only enough pressure to the gage and gage block to result in the dial indicator pointer settling at a reading Gently rock the two surfaces together to make sure that they have come together flatly The gage pointer should now line up exactly with the zero mark on the gage If it does not inspect and clean the gage and gage calibration block again and repeat this process If the gage pointer still does not line up with the zero mark on the gage loosen the dial lock screw and turn the graduated dial until the gage pointer exactly lines up with zero Then re tighten the lock screw Gages should be checked often to make sure that the zero setting has not changed Generally when the gage pointer on a gage that has been zeroed recently does not line up exactly with the zero mark the gage or calibrat
298. inserting tip of screwdriver between back edge of trim and front handle 3 and pulling forward Remove four screws 4 and one front handle assembly 3 per side Attach one rack mount flange 2 with four panhead screws 4 per side Remove feet and tilt stands 5 before rack mounting Save flathead screws and front handle assemblies for reuse when shipping Figure 2 2 Option 908 Rack Mounting without Front Handles Installation 8757 Option 913 Installation Instructions 1 Remove each front handle trim 1 by inserting tip of screwdriver between back edge of trim and front handie 3 and pulling forward Remove four flathead screws 4 and one front handie assembly 3 per side Attach one rack mount flange 2 and one front handie assembly 3 with four panhead screws 4 per side Remove feet and tiit stands 5 before rack mounting Save flathead screws for reuse when shipping oe ow m Figure 2 3 Option 913 Rack Mounting with Front Handles HP 8757C Installation 2 7 2 8 HP INTERFACE BUS AND 8757 SYSTEM INTERFACE CONNECTORS AND CABLES The HP INTERFACE BUS connector J2 is located on the rear panel of the analyzer J2 allows the analyzer to be connected to a controller via HP IB with or without additional instruments An illustration of pin configuration and signals on the HP IB connector is given in figure 2 4 The 8757 SYSTEM INTERFACE connector J1 is located on the rear panel of the ana
299. internal save recall registers of the analyzer source combination then recall it when needed You have two additional options with HP IB the interrogate function and the learn string With the output interrogated parameter function OP you can selectively interrogate the values of all functions that have numeric values such as frequency and number of trace points This function oper ates the same way in both the analyzer and the source It is illustrated in program 3 where the source start and stop frequencies are interrogated in lines 110 through 140 For a more thorough approach use the learn string functions of the analyzer and source The learn string describes the present instrument state and is similar to one of the internal save recall registers For the analyzer the learn string also includes all of the global parameters but does not include limit line information Once an instrument state is learned the analyzer and source states can be restored at any later time The following program demonstrates how to both learn and restore the instrument states of the HP 8757C E and the HP 8350B Sweep Oscillator by using their learn string functions If you use the HP 8340B 8341B or 8360 series Synthesized Sweepers perform the modification described at the end of Running program 10 Program 10 listing 10 REM INCLUDE GBSETUP 20 CLS 30 Maxsna 150 40 Maxswpr 90 50 ISC amp 7 60 Snak 716 70 Passthru 717
300. ion block needs cleaning Clean both of these carefully and check the zero setting again Measuring Connectors Measuring the recession of the center conductor behind the outer con ductor mating plane in a connector is done in exactly the same way as zeroing the gage except of course that the graduated dial is not re set when the measurement is made If the connector has a retractable sleeve or sliding connector nut precision 7mm connectors for example extend the sleeve or nut fully This makes it easier to keep the gage centered in the connector Hold the gage by the plunger barrel and slip the gage into the connector so that the gage plunger rests against the center conductor Carefully bring the gage into firm contact with the outer conductor mating plane Apply only enough pressure to the gage as results in the gage pointer settling at a reading Gently rock the connector gage within the connector to make sure that the gage and the outer conductor have come together flatly Then read the recession or protrusion from the gage dial For maximum accuracy measure the connector several times and take an average of the readings Rotate the gage relative to the connector between each measurement To monitor connector wear record the readings for each connector over time 20 Mechanical Connection AAA rere
301. ion is still on Measurement CHANNEL 2 CHAN 1 OFF Source parameters AF 250 MHz SAVE 2 Measurement Connect DUT ALT n 1 Still set for B R measurement Alternates current display data stored in register 2 with the source parameters stored in register 1 1 eum B A g3 i 1 0 d5 WEF 1 00 dB E eae EU sic sosere The traces should be scaled for optimal presentation of data When the measurement is completed pressing the ALT n hardkey again will deactivate the alternate sweep function Available only on the HP 8757C To deactivate a channel on the HP 8757E press it s hardkey until the channel turns off 21 External disk Save Recall Using the external storage capabilities of the HP 8757C facilitates greater productivity by allowing the user unlimited storage of measurement setups and data Fre quently used test setups may be easily recalled for use by numerous test station operators ensuring consistent device measurement When secure measurement environments are necessary the measurement may be stored externally without displaying any frequency annotation frequency blanking is described in the following chapter Test station operators may then utilize the prepared measurement parameters without re quiring direct knowledge of the frequency settings This chapter describes how to set up the disk drive initialize the disk and utilize the external
302. ion mode adaptive normalization HP 8757C etc of the active register must be the same as the analyzer settings of the register that will be alternated 9 the source or measurement parameters of a trace select the desired channel to make it active The source s front panel settings for that channel will now be displayed Changing the source parameters of a cali brated trace will cause it to become uncalibrated unless adaptive normalization HP 8757C is activated prior to reducing the frequency span 9 Channel1 should be the active channel of one storage register channel 2 should be active in the other register The following sequence presents a simultaneous measure ment of a filter s passband ripple and out of band rejection Preset Connections Connect DUT as for insertion loss measurement Controls 1 Set up storage register 1 Measurement CHANNEL 1 MEAS B R CHANNEL 2 IMEAS B R Source parameters CF 10 24 GHz AF 2 GHz POWER LEVEL 10 dBm dB Calibrate With the HP 8757C perform a thru calibration on channels 1 and 2 then follow the sequence below utilizing adaptive normalization On the HP 8757E channel 2 will require a thru calibration at the narrower frequency since the adaptive normalization function is not available CHANNEL 1 CHAN 2 OFF SYSTEM ADPT NRM ON OFF HP 8757C only SAVE 1 Controls 2 Set up storage register 2 Adaptive normalizat
303. ir this product must be returned to a service facility designated by HP Buyer shall prepay shipping charges to HP and HP shall pay shipping charges to return the product to Buyer However Buyer shall pay all shipping charges duties and taxes for products returned to HP from another country warrants that its software and firmware designated by HP for use with an instrument will execute its programming instructions when properly installed on that instrument HP does not warrant that the operation of the instrument or software or firmware will be uninterrupted or error free LIMITATION OF WARRANTY The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by Buyer Buyer supplied software or interfacing unauthorized modification or misuse operation outside of the environmental specifications for the product or improper site preparation or mainte nance NO OTHER WARRANTY IS EXPRESSED OR IMPLIED HP SPECIFICALLY DISCLAIMS THEIMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE EXCLUSIVE REMEDIES THE REMEDIES PROVIDED HEREIN ARE BUYER S SOLE AND EXCLUSIVE REMEDIES HP SHALL NOT BE LIABLE FOR ANY DIRECT INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES WHETHER BASED ON CONTRACT TORT OR ANY OTHER LEGAL THEORY ASSISTANCE Product maintenance agreements and other customer assistance agreements are available for Hewlett Packard products For any ass
304. is to save the instrument state in one of the nine internal save recall registers of the analyzer source combination then recall it when needed You have two additional options with HP IB the interrogate function and the learn string With the output interrogated parameter function OP you can selectively interrogate the values of all functions that have numeric values such as fre quency and number of trace points This function operates the same in both the analyzer and the source It is illustrated in program 3 where the source start and stop frequencies are interrogated in lines 80 through 130 For a more thorough approach use the learn string functions of the analyzer and source Learn string describes the pre sent instrument state and is similar to one of the internal save recall registers For the analyzer the learn string also includes all of the global parameters but does not include limit line information Once an instrument state is learned the analyzer and source states can be restored at any later time The following program demonstrates how to both learn and restore the instrument states of the HP 8757C E and the HP 8350B Sweep Oscillator by using their learn string functions If you use the HP 8340B or 8341B Synthe sized Sweepers perform the modification described at the end of Program 10 Explanation Program 10 listing 10 20 30 i 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
305. is voltage can be displayed in volts on any channel Video Output Three BNC connectors used to drive external monitors with the following characteristics R G B with sync on green 75 ohm impedance 1 V p p 0 7 V white 0 V black 0 3 V sync HP IB CHARACTERISTICS Interface HP IB operates according to IEEE 488 1978 and IEC 625 interface standards Interface Function Codes SH1 AH1 T6 TEO L4 LEO 591 RL1 CO E1 Transfer Formats Data may be transferred either as ASCII characters or as 16 bit integers most signifi cant byte first Readings may be taken at a single point or an entire trace may be transferred at once Transfer Speed includes command to initiate output ASCII format 401 point trace 500 ms typical ASCII format single point 10 ms typical Binary format 401 point trace 30 ms typical Binary format single point 7 ms typical Programmable Functions All front panel functions except power on off are programmable The HP 8757C E is compatible with all appropriate HP 8757A Scalar Network Analyzer programming codes User Accessible Graphics The user can generate on screen graphics using a subset of HP GL com mands Interrupts HP IB service interrupts SRQs are generated for the following conditions Front panel key pressed Numeric entry completed Soft key only pressed Limit test failed Operation complete sweep or plot Action requested not possible Syntax error
306. ission input B Line 130 Seta start time using the TIMER function in 12 QuickBASIC Line 140 Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260 Line 270 Line 280 Line 290 Line 300 Line 310 Line 320 Line 330 Set an initial stop time to be compared to the start time Loop until 2 seconds have elapsed from the start time Update the time End of the 2 second loop Set the data format to Extended ASCII and command the analyzer to output the channel 1 measurement data Initialize the variable specifying the number of elements actually read into the array Read the measurement trace data from channel 1 Perform error trapping Disable the end of line string carriage return linefeed that is sent after any IOOUTPUT command Command the analyzer to input data into the trace memory of channel 1 Enable the end of line string carriage return linefeed that is sent after any IOOUTPUT command Write the measured trace data back to the trace memory of channel 1 Reading the measurement trace and storing it back into trace memory is equivalent to executing the MEAS MEM function HP IB command SM Perform error trapping Command channel 1 to display the trace memory data Press EN TER to continue Print a message on the computer s CRT notifying the user that the computer is waiting for a key to be
307. istance contact your nearest Hewlett Packard Sales and Service Office Addresses provided at the back of this manual BP21 1 SAFETY CONSIDERATIONS GENERAL This product and related documentation must be reviewed for familiarization with safety markings and instructions before operation This product has been designed and tested in accordance with international standards SAFETY SYMBOLS Instruction manual symbol the product will be marked with this symbol when it is necessary for the user to refer to the instruction manual refer to Table of Con tents Indicates hazardous voltages Indicates earth ground terminal The WARNING sign denotes a hazard It calls attention to a pro m cedure practice or the like which if not correctly performed or adhered to could result in personal injury Do not proceed beyond a WARNING sign until the indicated conditions are fully understood and met The CAUTION sign denotes a hazard it calls attention to an VU operating procedure practice or the like which if not correctly performed or adhered to could result in damage to or destruc tion of part or all of the product Do not proceed beyond a CAU TION sign until the indicated conditions are fully understood and met SAFETY EARTH GROUND This is a Safety Class product provided with a protective earthing terminal An uninterruptible safety earth ground must be provided fro
308. ive channel is boxed to differentiate it from other enabled channels The HP 8757C may display as many as four channels at one time Selecting one of the channel hardkeys will activate the CRT displayed channel menu The softkeys may then be uti lized to activate or deactivate other channels The HP 8757E has dual channel capabilities The trace and labels of the active channel are displayed more brightly selecting that channel again deactivates it Sus CHANNEL Function selection There are eight function keys which allow the user to select the measurement parameters calibrate and manipulate data presentation MEAS DISPLAY and CAL access menus which provide the user with a choice of measurement and display configurations and calibration sequences The SCALE REF CURSOR AVG and SPCL keys allow the user to manipulate information in a manner that enhances usability of the measured data FUNCTION Data entry The ten digit keypad is used to enter numeric values for a chosen parameter Once the numbers have been selected they need to be terminated with the appropriate units located on the right side of the keypad Use ENT to termi nate data that is unitless In addition to entering data with the keypad the knob may be used to make continuous adjustments while the and 9 keys allow the values to be changed in steps Instrument state selection The Instrument State keys control sy
309. l for installation Set the interface select code to 7 1 Turn on the HP 8350B Sweep Oscillator Press SHIFT LCL The FREQUENCY TIME display shows the current HP IB address of the source If itis not 19 press 1 9 GHz to set the address to 19 The HP 8340B or 8341B Synthesized Sweeper operates the same although the address is displayed in the right hand display area For the HP 8360 access the HP IB menu under the SYSTEM MENU key Verify that the address is 19 and programming language is Analyzer 2 Power on the HP 8757C E Scalar Network Analyzer The current HP IB address is shown in the active entry area of the CRT If itis not 16 press LOCAL 8757 1 6 ENT to set the address to 16 3 Load Microsoft QuickBASIC by typing GB L GBHP IB at the MS DOS prompt Check out procedure Press PRESET on the analyzer If the 8757 SYSTEM INTERFACE is properly connected and the address of the source correctly set both the analyzer and the source will perform an instrument preset If either instrument detects a failure during instrument preset that instrument displays the error encountered The operating manual of the source gives instructions to help you interpret the error message If the analyzer displays an error message see In Case of Difficulty Programming examples In the following sections example programs introduce the HP IB capabilities of the analyzer Each example program consists of these sec
310. le Out of Band Rejection Adaptive Normalization Measuring Active Devices Gain Compression Chapter 3 17 Reflection measurements with the HP 8757C E Signal Separation Device Termination Measurement Accuracy Measurement Setup for Return Loss and SWR Return Loss SWR Chapter 4 19 Limit lines Accessing the Limit Line Menu Creating Limit Lines Editing Limit Lines Creating Limit Lines for a Bandpass Filter Chapter 5 21 Alternate sweep Chapter 6 22 External disk save recall Setting Up the Disk Drive Intializing a Blank Disk Save Recall Functions Chapter 7 24 Special functions Color Selection Frequency Blanking Appendix 25 AC versus DC detection Index 26 Operating the HP 8757C E Front panel tour The front panel of the HP 8757C E was designed to simplify measurement operations Each hardkey accesses a CRT displayed menu These menus offer a list of possible selec tions for the completion of a particular operation Each selection corresponds to one of the eight softkeys located to the right of the display Using front panel keys to access softkey menus allows for the expansion of the analyzer s capabilities without adding front panel complexity CRT display With the selection of each hardkey or softkey the HP 8757C E s display is updated to exhibit the current measurement configuration and status information For those parameters not continually shown on the display select the ap
311. le Type Extension Instrument State IS File identities are determined by their extensions For example a Measurement Data Channel 4 Dq normalized data file for channel 2 named FILE1 would have N2 Memory Data Channelq Mq appended resulting in FILE1N2 CRT Graphics CG Normalized Data Channel Nq Where q represents a channel number 1 to 4 Table7 HP 8757C E Status Byte Descriptions STATUS BYTE 1 Decimal 5 Function EXTENDED STATUS BYTE 2 NX ef Value SRQ on SRQ on SRQon SRQ on SRQon SRQon Detector Front Panel Limit Test Action Knob Self Test Uncal Preset or Failed Requested Activity Failure Power on not possible Service Operation Softkey Change in Numeric Front Panel SRQ Syntax Error Complete Only Extended Entry Key Pressed Sweep Plot Pressed Status Byte Completed or Print HP IB or Front Panel Table8 Front Panel Keycodes values are in decimal SOFTKEYS ENTRY Softkey 1 top 32 Step down 22 Softkey 2 8 Step up 6 Softkey 3 0 0 Key 20 Softkey 4 16 iKey 4 Softkey 5 14 2 3 Softkey 6 38 3 Key 7 Softkey 7 40 4Key 12 Softkey 8 bottom 41 5 Key 11 6Key 15 CHANNEL 7 Key 36 Channel 1 42 8 Key 35 Channel 2 43 9 Key 39 Key 19 FUNCTION Key 23 Measurement 44 Entr
312. leaning 12 Cleaning Interior Surfaces interior surfaces especially on 3 5mm connectors are very difficult to reach and it is easy to damage connectors in trying to clean them The openings are very small and generally the center conductor is supported only at the inner end by a plastic dielectric support bead This makes it very easy to bend or break the center conductor One suitable method Figure 5 is to cut off the sharp tip of a round wooden toothpick and then to wrap it with a single layer of lint free cleaning cloth A round wooden toothpick or a very small diameter wooden rod is required metal must never be used it will scratch the plated surfaces and in cleaning precision 3 5mm connectors the diameter must not exceed 0 070 in 1 7 mm The wooden handle of a cotton swab for example is too large for this purpose Even though the handle can sometimes be inserted into the connector even when wrapped in lint free cloth movement of the handie against the center conductor can exert enough force on the center conductor to damage it severely Moisten the cloth with a small amount of cleaning solvent and carefully insert it into the connector to clean the interior surfaces Use an illuminated magnifying glass or microscope to see clearly the areas you wish to clean Precision 7mm Connectors When precision 7mm connectors have been cleaned with the cen ter conductor collet removed insert the collet and clean the mating plane
313. lf Calibration in this section for more details TEMPCMP ON OFF gives you control over the analyzer s continuous temperature compensation Pressing this softkey toggles temperature compensation on and off See HP 8757C E Self Calibration in this section for more details PRIOR MENU returns the first calibration menu HP 8757C E Self Calibration The calibration menu softkeys CONFIG SYSTEM AUTOCAL ON OFF and TEMPCMP ON OFF all relate to the analyzer s internal calibration With AUTOCAL ON and TEMPCMP ON all internal calibration is done automatically and is transparent to the user The analyzer automatically maintains absolute and dynamic power accuracy for each detector input using two independent digital correction processes Autocalibration A regeneration of the internal calibration tables whenever The accessory configuration is changed A significant change in temperature occurs approximately 5 C Temperature Compensation A continuous compensation for small changes in temperature Both of these correction processes can be controlled in the second calibration menu At preset or power on both autocalibration and temperature compensation are on and all internal calibration is performed automatically AUTOCALIBRATION With AUTOCAL ON the internal calibration tables are updated automatically AUTOCAL ON is recommended for most applications The analyzer may update its internal calibr
314. libration without changing the analyzer s display mode The analyzer automati cally measures the calibration standards stores the data at the highest resolution and returns the display mode you had previously set SHORT OPEN prompts you through a short open calibration This calibration is automatically stored in memory in dB dBm format When the SHORT OPEN softkey is pressed the prompt CONNECT SHORT STORE HHEN READY appears on the CRT and a second menu layer is presented Operating Reference HP 8757C E AVERAGE ON OFF toggles averaging on and off This is the same averaging function that is engaged by pressing AVG ON OFF in the averaging menu If you had previously turned averaging on it will automatically be toggled off when SHORT OPEN is pressed Pressing AVERAGE ON OFF toggles averaging on only for the measurement of the short The averaging factor does not change from the last value set in the averaging menu You must return to the averaging menu if you wish to change the averaging factor STORE SHORT measures the short circuit response Connect the short to the test port of the bridge or detector being used and press STORE SHORT The message CONNECT OPEN STORE WHEN READY appears on the CRT and a third menu layer is presented AVERAGE ON OFF toggles averaging on and off If you used averaging when measuring the short you should use averaging to measure the open Averaging has automatically been turned off again
315. lid plastic dielectric in front of the outer conductor mating plane sometimes as much as 0 002 or 0 003 inches This is not necessarily harmful when SMA connectors are mated to one another because some compression of the dielectric can occur But it can be extremely harmful if the SMA connector is mated to a precision 3 5mm connector The protruding dielectric can force the rigid center conductor of the precision 3 5mm connector back through the connector itself damaging not only the connector but sometimes the device to which it is attached For this reason SMA connectors in which the solid plastic dielectric protrudes in front of the outer conductor mating plane must never be mated to precision 3 5mm connectors Always inspect SMA connectors for protrusion of the solid plastic dielectric before mating them to precision 3 5mm connectors Protrusion of the dielectric can also occur due merely to connection and disconnection The mechan ical force of pulling the connectors apart can result in movement of the dielectric Aging and tem perature cycling can also cause the dielectric to move out of specification Out of Specification SMA Male Pins The other main source of problems is the SMA male pin Partly because low manufacturing costs are desirable in SMA connectors the male contact pins in some SMA connectors are not held securely in position These pins are very easily pulled out of specification especially if the female contact fingers in t
316. llet from the connector The collet removing tool required for this purpose is supplied in many Hewlett Packard calibration kits and is also available separately as HP Part Number 5060 0236 Two types of center conductor collets exist 4 slot collets HP Part Number 1250 0907 and 6 slot precision collets HP Part Number 85050 20001 The two types are interchangeable and the 6 slot type is recommended for maximum durability and repeatability of connections Both types of collets can be re used after they are removed but before doing so the collet should be inspected carefully Look especially for edge or surface damage and for any signs that the spring contacts are bent or twisted If they are replace the collet and the collet removing tool No damage to the collet should occur due to the removing tool To insert a collet pick up the collet by the slotted end using tweezers and insert it carefully flat end first into the center conductor of the connector Press the collet gently until it snaps into place using a blunt plastic rod or the rounded plastic handle of the collet removing tool Do not use a pencil or your finger for this purpose When the collet has been re inserted verify that it springs back immediately when pressed with a blunt plastic rod or the rounded plastic handle of the collet removing tool When removing or replacing collets in test port connectors take care to avoid electrostatic discharge Wear a grounded wri
317. lotting coordinates Multi way branch on the Pen_mode value If Pen mode is D then we want to draw Draw to coordinates X Y If Pen_mode is M then we want to move Move to coordinates X Y End of multi way branch End of the repeat loop Repeat lines 160 through 220 again if Pen mode isn t E If it was then we are done plotting the data in the data statements Move the pen to title our display 15 Line250 Title the display with the label CONNECTION DIAGRAM This shows one way to label the analyzer display by using its internal character set To do this we must first specify which set to use via the SI command This specifies the width and height respectively of each character and is similar to the computer s CSIZE instruction We indicate what the label is with the LB command and follow it with the label We must terminate the label with an end of text ETX character a byte equal to a binary 3 Line260 Move the pen to label our device under test DUT Label the DUT using the computer s LABEL statement Notice the difference between this label and the one generated in line 250 First the intensity is less Second the characters look more round and smooth This is because the computer generates each character by plotting several small strokes more than the HP 8757C E s internal CRT does for its characters This means that you will also use much more graphics memory tha
318. ludes the horizontal and vertical graticule lines in the custom plot format MODE LABELS includes the mode labels in the custom plot format FREQ LABELS includes the frequency labels in the custom plot format unless they are turned off with FRQ LBL OFF SCALE TO P1P2 expands the plot so that the lower left corner of the grid is at the P1 position of the plotter and the upper right corner of the grid is at the P2 position of the plotter Mode labels and frequency labels are plotted outside of the grid unlike the HP 87574 DONE terminates the definition of the custom plot format When pressed this softkey returns the plot menu PRIOR MENU also terminates the definition of the custom plot format and returns the plot menu ABORT PLOT terminates plotting of a plot currently in progress Plotting does not stop immedi ately it stops after the buffer empties PRIOR MENU returns the previous menu system menu HP 8757C E Operating Reference 35 36 Printing H 757E SYSTEM HP 8757C HP 8757 Figure 21 Print Menus PRINT presents the print menus The print menus are shown in figure 21 PRINT allows you to print data to a printer capable of generating a graphics plot or tabular listings The analyzer is designed to be compatible with the HP 2255A ThinkJet the HP 3630A PaintJet and the HP 2227B QuietJet Plus Other Hewlett Packard printers not listed here may also be compatible with the analyzer Pressing the PRIN
319. lyzer The system interface connects the analyzer to the HP IB connector of compatible instruments The analyzer itself controls the system interface Do not connect a controller to this connector An illustration of J1 is given in figure 2 4 All instruments on the HP IB or the system interface are interconnected by HP IB cables HP IB cables are available in lengths from 0 5 m 1 6 ft to 4 m 13 2 ft See Replaceable Parts for ordering information As many as fifteen instruments may be connected in parallel on the HP IB or the system interface To achieve design performance on the bus proper voltage levels and timing relationships must be maintained If the system cable is too long or if the accumulated cable length between instruments is too long the data and control lines cannot be driven properly and the system may fail to perform Observe the following restrictions e 4m 12 ft is the maximum cable length with two instruments in a system e 2m 6 ft is the maximum cable length to each instrument when more than two instruments are connected on the bus e 20 65 ft is the maximum total cable length between all units Installation HP 8757C E 8757 System Interface Connector J1 and HP Interface Bus Connector J2 as viewed from rear of instrument SIGNAL GROUND P O TWISTED PAIR WITH 11 P O TWISTED PAIR WITH 10 GROUNDED NEAR P O TWISTED PAIR WITH 9 TERMINATION OF OTHER WIRE OF P O TWISTED PAIR WITH 8 TWISTED PAIR
320. lyzer and the source When presetting the analyzer and source send the PRESET com mand only to the analyzer The analyzer will preset the source attached to the 8757 SYSTEM INTERFACE HP 8757C E instrument preset conditions Channels 1 and 2 on The channel menu appears in the softkey label area of the CRT Measure power on channel 1 Measure power B on channel 2 Measure power C or B2 on channel 3 Measure power on channel 41 Scale 20 dB div Reference level 0 dB for all channels Reference level step size 20 dB Averaging off Averaging factor 8 Cursor off All labels on Channel 1 as the active channel Modulation drive on Number of points 401 Detector mode set for AC detection Smoothing set for 5 096 of span off Cursor format log magnitude Search value 3 Adaptive normalization off Temperature compensation on Repeat autozero off Source Instrument preset Sweep time set to 200 ms HP 8350B square wave modulation on HP 8340 41SHIFT PULSE on RF Output on HP 8360 scalar modulation on RF output on ramp sweep mode analyzer mode Plotter e Abort plotif in progress PlandP2scaling points unchanged e Selection of plotter pens unchanged Printer e Abort plotif in progress Disk drive e Aborts any data transfers in progess Unit number unchanged Volume number unchanged e ASCII or binary mode unchanged The following analyzer conditions ar
321. m execution Running program 6 1 Clear the program memory of the computer and type in the program Press RUN on the computer Watching the analyzer CRT you will see DATA DUMP TO HP 1B when it begins sending trace data to the com puter and DATA DUMP TO TRACE MEMORY when the computer sends the data back The transfer takes about 800 milliseconds each way ASCII transfer Watching the analyzer CRT press Continue on the computer The computer again reads and writes a trace of data and the analyzer displays the same messages The transfer is very fast about 35 milliseconds each way binary format Press Continue on the computer The computer calcu lates an arbitrary function and sends it to a trace memory of the analyzer where it is autoscaled and displayed This function a sawtooth pattern has no significance It represents a special calibration trace such as a short open average With a computer the analyzer measure ment system may be calibrated over several different frequency ranges and changed from one to another very quickly without re calibration When writing memory traces in ASCII format be sure to set the analyzer to ratio or single input measurements before sending the trace If you wish to transfer a higher resolution trace modify line 50 to be IP SP801 for 801 points Then modify the 400 in lines 60 70 and 190 to 800 Program 7 using the TAKE SWEEP command To make measurements as q
322. m interface is turned on NOTE Alternate state information cannot be saved on disk If an attempt is made to save alternate state the analyzer disables the alternate sweep mode The following procedure demonstrates how to implement the alternate sweep feature 1 Setup the analyzer for the desired measurement on channels 1 and 2 A B R A R B R and so on Turn channels 3 and 4 off 2 Define one of your source states as the primary configuration and the other as the secondary alternate configuration For the above filter measurement the broadband sweep could be defined as the primary configuration this will be measured and displayed on analyzer channel 1 and the narrowband sweep as the secondary this will be measured and displayed on analyzer channel 2 3 Select channel 2 and set up the source for the secondary configuration gt For anormalized measurement calibrate the system and set the analyzer to display MEAS MEM on channel 2 Store this state in analyzer register 2 Select channel 1 and set up the source for the primary configuration For a normalized measurement calibrate the system and set the analyzer to display MEAS MEM o om Store this state in analyzer register 1 HP 8757C E In Case of Difficulty 5 6 9 Activate the alternate sweep function on the source and enter register 2 as the alternating register if implemented as described above the source will alternate between the sweep conditions
323. m the main power source to the product input wiring ter minals power cord or supplied power cord set Whenever it is likely that the protection has been impaired the product must be made inoperative and secured against any unintended operation BEFORE APPLYING POWER Verify that the product is configured to match the available main power source per the input power configuration instructions provided in this manual If this product is to be energized via an auto transformer make sure the common terminal is connected to the neutral grounded side of the mains supply SERVICING WARNING Any servicing adjustment maintenance or repair of this product must be performed only by qualified personnel Adjustments described in this manual may be performed with power supplied to the product while protective covers are removed Energy available at many points may if contacted resuit in personal injury Capacitors inside this product may still be charged even when disconnected from their power source To avoid a fire hazard only fuses with the required current rating and of the specified type normal blow time delay etc are to be used for replacement HP 8757C OPTION 001 SCALAR NETWORK ANALYZER POWER CABLE HP IB INTERFACE CABLE Power cable plug supplied depends on country of destination Refer to Section 2 for part number information Figure 1 1 8757C Option 001 Scalar Network Analyzer and Access
324. malized trace measure ment minus memory In addition the memory trace can be written back to the analyzer allowing you to save and restore calibration traces via HP IB With trace transfer measurements some frequency resolu tion is sacrificed for measurement speed The number of points per trace can be programmed to control the resolution across the frequency range being swept If you are measuring a device that changes very rapidly with frequency it is possi ble to miss very narrowband responses that occur between measurement points if the resolution is low For these cases the measurement should be made at a higher resolution The trace transfer method of measurement is much faster than CW point by point measurements Program 6 listing 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 180 190 200 210 220 230 240 250 260 270 280 290 310 320 330 340 REM INCLUDE CLS 15 7 Sna amp 716 DIM Ascii datki TO 401 Binary dat z 1 401 Max1X 401 Max2 2 Max1 CALL IOTIMEQUTCISC amp 101 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR CALL IDABORTCISCa IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR CALL IOCLEARCISC amp IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A IP GOSUB IQQUTS QGBSETUP AS CILA C218 GOSUB IGOUTS Start TIMER Stopped TIMER DO UNTIL CStopped Start gt 2 Stopped TIMER
325. may induce a DC voltage offset at the diode s output AC detection minimizes this problem by measuring only the modulated RF signal thus ignoring the DC offset Detector sensitivity to thermal change is a primary concern when measuring device perfor mance as a function of temperature particularly at low power levels less than 40 dBm AC detection is the best broadband measurement technique for mixer testing The presence of high level LO feedthrough at the IF port of the mixer under test will impact the accuracy and dynamic range of the scalar analyzer if DC detection is used When the analyzer is operated in AC detection mode the effect of the LO feedthrough is minimized by modulat ing the RF signal and leaving the LO signal un modulated thus the detector will respond only to the modulated IF Using IDC detection Certain devices require DC detection mode for the best results Amplifiers with automatic gain control AGC are adversely affected by the modulation in AC detection mode The leveling circuitry unsuccessfully tries to adjust the gain to track the modulation the resulting square wave is dis torted degrading the scalar analyzer response Other modulation sensitive devices include amplifiers with slow responding self bias devices with high gain at very low fre quencies lt 1 MHZ and devices with very narrow bandwidths lt 1 MHz Absolute power dBm measurements may be more accurate in DC detection mode sin
326. med on the averaged data The average menu is used to turn averaging on or off to set the average factor and to restart the averaging process after it is turned on AVG ON OFF toggles on and off the averaging function for the active channel The averaging factor is shown in the active entry area The status symbol A is shown in the mode labels area for any channel that has averaging turned on RESTART AVERAGE starts the averaging process from the beginning AVG FACTOR lets you set the averaging factor The averaging factor is shown in the active entry area The analyzer defaults to an averaging factor of 8 at preset and power on You can set the averaging factor to 1 2 4 8 16 32 64 128 or 256 If you try to set the averaging factor to any other value the analyzer automatically changes it to the first allowed value that is lower than your entry Use the knob STEP keys or numeric keypad Terminate the entry with the ENT key HP 8757C E Operating Reference 21 22 CAL CALIBRATION MENUS HP 8757C E FUNCT ION HP B757C OPT 001 ONLY SEE HP85028C OPERATING AND SERVICE MANUAL Figure 15 CAL Key and Calibration Menus The CAL key presents the calibration menus These softkeys allow you to perform and store calibrations Use these softkeys also to perform detector zero calibrations to set detector offsets and to turn on automatic internal calibration You can perform a ca
327. mize device variation You can modify this test to use other microwave devices and test specific frequency ranges but if you use a different RF plug in that cannot output 16 dBm you will not be testing the analyzer s full dynamic range EQUIPMENT HP IB Cable HP 10833A B C D Sweep Oscillator Mainframe HP 8350B RE PION tiie eet quat bai Gut p dpa eee EA HP 83592B Detector RN 11664A E 50 MHz Bandpass Filter HP Part Number 08757 80027 Graphics Plotter HP 7440A PROCEDURE 1 To verify the instrument self tests HP IB and 8757 system interface private bus perform the Interface Bus and 8757 System interface performance test in section 4 of the service manual HP 8757C E 18 8757 SYSTEM INTERFACE SHEEP NE THORK OSCILLATOR ANALYZER on te MICR HRVE TEST DEVICE Figure 32 Equipment Set up for Operator s Check Operating Reference 63 64 e N 9 10 11 12 14 Set up the equipment as shown in figure 32 with the detector connected to input A of the analyzer Connect the detector s RF input to the RF output of the source for a thru 0 dB insertion loss connection Turn on the instruments and allow 30 minutes warm up time If the 8757 system interface is not engaged SY S INTF OFF appears in the status line o
328. mmed automatically Other Configurations The analyzer can be operated with the sources already described without connecting the 8757 System Interface In this configuration make the connections to the analyzer s POS Z BLANK and SWEEP IN 0 10 V only Use this configuration also with the HP 8620 series Sweep Oscillator and with non Hewiett Packard sources Modulation is achieved by connecting the MODULATOR DRIVE to the source PULSE input or an external modulator can be used such as the HP 11665B gt 5 HP 8757 875 JC ONL Y e ei a ani in loan LAEE ITOR INTERCONNECTIONS 4 B The analyzer is capable of driving both the internal display and one external monitor simul taneously An exter nam onitor may be connected to the analyzer using the three BNC connectors on the rear panel of the instrument These three Red Green Blue RGB connectors provide compatible video signals for an HP 357414 B monitor To use the external monitor connect the three RGB BNC outputs from the rear panel of the analyzer to the corresponding RGB inputs of the monitor Other multisync monitors can be used if they are compatible with the S 25 5 kHz scar rate and video levels 1 V p itd ie 7 A us ode 3 Yy pus on green Use Amonochrome monitor such as the HP 35731A B may also be used if the analyzer is operated in monochrome mode in this case connect only the gre
329. n with the internal character set Line 270 Line280 Define the start of the data statements containing our plotting information for all of the lines on the CRT While these may be less legible than lots of MOVEs and DRAWS it is more efficient programming Line290 This data statement draws the outline of the source Line 300 Line 310 This data statement draws the RF plug in This data statement draws the outline of the analyzer Line320 This data statement draws the CRT of the analyzer Line330 This data statement draws the connections from the source to the DUT Line340 This data statement draws the connections from the DUT to the analyzer Line350 This data statement draws the DUT an amplifier Line360 This data statement indicates the end of our plotting The X and Y values are needed here only for the read statement in line 160 Line370 End program execution Running program 9 1 Clear the program memory of the computer and type in the program 2 Press RUN on the computer 16 3 After the analyzer and source are preset the CRT will be blanked First a grid is plotted on the CRT While this isn t necessary for our connection diagram it does give you a good indication of where the X and Y coordinates are on the analyzer s CRT 4 Allofthe lines are plotted on the analyzer s CRT These are just a sequence of MOVEs and DRAWS as specified by the data statements If brighter lines are d
330. n SMA and precision 3 5mm connectors or for changing the sex of a connector interface The HP 85052 series adapters available in all three types are high performance adapters that can be used in any application The HP 85027 series adapters available in male female and male male form only are designed to be used only with HP 85021 27 series directional bridges 7mm to 3 5mm or SMA Adapters Devices or cables that have SMA or precision 3 5mm connectors can be connected to devices or cables that have a precision 7mm interface using the 7mm to 3 5mm or SMA adapters shown in Figure 25 This use of adapters is especially recom mended to reduce wear on connectors that may be difficult or expensive to replace Adapters with precision 6 slot collets are recommended for the utmost in repeatability and performance Adapters with 4 slot collets are good general purpose adapters SMA and Precision 3 5mm Connectors 61 3 5mm to 3 5mm ADAPTERS SMA COMPATIBLE female 3 5mm male 3 5mm j male 3 5mm male 3 5mm HP Part Number 1250 1866 HP Part Number 1250 1864 female 3 5mm female 3 5mm HP Part Number 1250 1865 3 5mm CONNECTOR SAVERS FOR HP 85021 27 DIRECTIONAL BRIDGES male 3 5mm male 3 5mm female 3 5mm male 3 5mm HP Part Number 85027 60003 HP Part Number 85027 60002 Figure 25 3 5mm Adapters 1 of 2 62 SMA and Precision 3 5mm Connectors 7mm to 3 5mm SMA COMPATIBLE ADAPTERS
331. n off CW mode on off Cursor to maximum Detector A offset set to d Detector B offset set to d Detector C offset set to d Set default colors Set disk format to ASCIP Set disk format to binary Display Hold on off of the active channel trace Set disk HP IB address Set disk unit number Set disk volume number Delete file from disk Allinputs set to DC detection All inputs set to AC detection Step down decrement Detector R offset set to d Display trace data in log magnitude Display trace data in standing wave ratio SWR format Erase all save recall registers Start frequency label Stop frequency label Format data ASCH Format data binary HP BASIC compatible Format data extended ASCII Format data binary PC compatible Input A absolute power measurement Input B absolute power measurement Input C absolute power measurement Input Learn string Initialize disk format Instrument preset Input R absolute power measurement External ADC input AUX voltage measurement Erase limit lines for active channel Load instrument information file from disk Load CRT graphics file from disk Load data trace file from disk Load instrument state file from disk Load memory trace file from disk Enter limit test flat line data Store lower limit line into memory Table 2 Alphabetical Listing of HP did Programming Codes 2 of 2 Enter limit test point data Enter limit test sloped line data Limit line test on off
332. n output is on In DC the modulation is off Both features can be manually overridden TITLE presents the title menu which is used to define a title that is shown on the CRT and plotted with the data The title is composed of characters selected from the CRT in the active entry area The letters of the alphabet the digits 0 through 9 a decimal point and the mathematical symbols are shown on the CRT with the message POINT WITH WITH KNOB SOFTKEYS THEN PRESS SELECT CHAR SELECT CHAR enters your character in the title Turn the knob or repeatedly press the STP ONE RIGHT or STP ONE LEFT softkey until the arrow points to the character you desire Press SELECT CHAR and the character appears in the title SPACE inserts a blank space in the title next to the last character entered BACK SPACE deletes the last character entered ERASE TITLE deletes the entire title STP ONE RIGHT moves the arrow pointer to the next character to the right STP ONE LEFT moves the arrow pointer to the next character to the left DONE terminates entry of the title and returns the system menu HP 8757C E Operating Reference 39 LADPT NM ON OFF toggles adaptive normalization on and off Adaptive normalization adjusts the calibration data stored in memory when ine frequency range is changed This makes it possible to narrow in on part of the calibrated frequency range without recalibrating The resolution of the narrower range view
333. n the information presented in previous chapters Also the examples provided within each chapter are written in procedural form To follow the examples start at the beginning of each chapter To simplify the execution of the measurements presented the HP 8757C s front panel hardkeys are differentiated from the display softkeys The hardkeys are presented in bold capital letters e g CAL and the softkeys are bold italic capital letters e g SHORT OPEN Equipment utilized in this guide HP 8350B Mainframe with HP 83592B Plug in Bandpass Filter HP Part No 0955 0446 HP 8447D Amplifier HP 85027E Directional Bridge Includes 3 5 mm f to f adapter HP Part No 85027 60005 and 3 5 mm f open short HP Part No 85027 60004 HP 11664A Detector HP 11664E Detector HP 11667A Power Splitter HP 8491A 6 dB Attenuator HP 8491B 10 dB Attenuator Type N m to 3 5 mm m adapter HP Part No 1250 1743 Type N m to 3 5 mm f adapter HP Part No 1250 1744 HP 85022 Cable Kit C N T E N T S Chapter 1 5 Operating the HP 8757C E Front Panel Tour General Measurement Setup Preset Setup Test Connections Set System Control Settings Perform Calibration Save Instrument State Measure Device Under Test Output Results Chapter 2 1 Transmission measurements with the HP 8757C E Basic System Configuration Measurement Setup for Insertion Loss and Gain Insertion Loss 3 dB Bandwidth Peak to Peak Ripp
334. n where the search value exists The analyzer will interpolate the point between two existing values and calculate the corresponding frequency when needed If the value cannot be found the message WARN ING Cursor Value not found Trace HOLD appears on the CRT In a normalized measurement the search function finds the n dB point from the 0 dB reference line in cursor A mode search values are found for the n dB points from the A marker moves to the right BANDWIDTH determines the trace bandwidth at a specified value down from the maximum trace value The n dB value for the bandwidth can be set with the STEP keys or the numeric keypad Terminate the entry with the dBm dB or ENT key The analyzer searches automat ically for the maximum trace amplitude then finds the n dB down points on both sides and shows the bandwidth in the active entry area BANDWIDTH effectively performs the follow ing series of functions CURSOR MAX or MIN CURSOR A ONT SEARCH set search value SEARCH LEFT write down the frequency SEARCH RIGHT write down the frequency f2 calculate 12 1 This function produces results only when an HP IB compati bie sweep oscillator or synthesized sweeper is used PRIOR MENU returns the first cursor menu HH rn red AAAA A aaea aaa aranana nann 1 SEARCH RIGHT works the same as the SEARCH L
335. na C1OD 270 ENTER Sna Ascii_dat 280 OUTPUT Sna SW1 290 END HP 8757C E Status Byte Descriptions Lg a ee 11 Program 7 explanation Line 10 Line 20 Line 30 Line 40 Line 50 Line 60 Line 70 Line 80 Line 90 Line 100 Line 110 Line 120 Line 130 Line 140 Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 12 Dimension an array large enough to hold a trace of data 401 points Assign an I O path to the address of the analyzer Assign an I O path to the passthru address of the analyzer Abort any transfers and clear the HP IB interface of the computer Clear the HP IB interface of the analyzer Preset the analyzer and source Tell the analyzer which device is controlled through the passthru address Address 19 belongs to the sweeper Set the source to 250 milliseconds per sweep Turn off channel 2 of the analyzer and select transmission input B for display on channel 1 Put the analyzer into non swept mode Clear the status register of the analyzer Set the request mask to 16 bit 4 so that the analyzer will set bit 4 operation complete at the completion of the TAKE SWEEP command Table 2 has a descrip tion of all bits in the status bytes Command the analyzer to take 10 sweeps Wait for the 10 sweeps to completed by reading the analyzer status byte Test the status byte to see if bi
336. na TO 716 50 ASSIGN Passthru TO 717 60 ABORT7 70 CLEAR Sna 80 OUTPUT g5Sna IP 90 OUTPUT Sna PT19 100 OUTPUT Passthru FA Start freq GZ FB Stop__freq GZ 110 OUTPUT Sna C2 CXOC 120 ENTER Sna Value Posn 130 PRINT Cursor reads Value dB at position Posn 140 INPUT Desired cursor position 0 400 New posn 150 OUTPUT gG5na SC INT New posn t 5 160 OUTPUT gSna OC 170 ENTER Sna Vaiue Posn 180 PRINT Value at position Posn is Value dB 190 INPUT Cursor frequency GHz Cur freq 200 New posn 400 Cur freq Start freq Stop freq Start freq 210 OUTPUT qGSna SC INT New posn T 5 220 OUTPUT gGSna OC 230 ENTER Sna Value Posn 240 Cur freq Start freq Stop freg Start freg Posn 400 250 PRINT Cursor reads Value dB at Cur freq GHz 260 END Program 4 explanation Line10 Direct the printed output to the computer CRT Line20 Define the start frequency of the desired sweep in GHz Line30 Define the stop frequency of the desired sweep in GHz Line40 Assign an I O path to the address of the analyzer Line50 Assign an I O path to the passthru address of the analyzer Line60 Abort any transfers and clear the HP IB interface of the computer Line70 Clear the HP IB interface of the analyzer Line80 Preset the analyzer and source This sets the number of points per trace to 401 Line90 Tell the analyzer which instrument is contr
337. nches in front of the outer conductor mating plane Such a connector is out of specification It will damage other connectors to which it is mated and should not be used Connection Technique in two important respects connections made between Type N connectors differ from those made between other connectors Type N connectors are never rotated relative to one another Type N connectors are connected finger tight Because Type N connectors are made of brass or in the case of HP Precision Type N connectors stainless steel special care should be taken to avoid rotating the mating plane surfaces against one another In particular the optional step recommended for seating precision 7mm connectors must never be used when connecting Type N connectors together A torque wrench is not needed and generally cannot be used in making the final connection of Type N connectors because the standard connector nuts on male Type N connectors do not have wrench flats Connections will be tight enough when the nuts are connected finger tight If a torque wrench is used for example a wrench equipped with a special non slip end the correct torque setting is the same as for precision 7mm connectors 12 Ib in 136 N cm As with other connectors always turn the connector nut only to tighten the connection Careful inspection and cleaning of Type N connectors is also essential and the recommendations on these subjects in Part One of this Microwave C
338. nd Library This com mand must appear before the body of the program whenever calls to the HP IB Command Library are to be made Line20 Clear the computer CRT Line30 Assign the interface select code to a variable This select code is set on the HP 82335A HP IB interface card Line 40 Assign the address of the HP 8757C E toa variable Line50 Define a system timeout of 10 seconds Timeout allows recovery from I O operations that aren t completed in less than 10 seconds Perform error trapping Line 60 Abort any HP IB transfers Perform error trapping Line 70 Clear the analyzer s HP IB interface Perform error trapping gt Line 100 Setthe analyzer and source to remote mode Line 80 Set the analyzer and source to remote mode Perform error trapping Line90 Press ENTER to continue Perform error trapping Line 110 Lock out the LOCAL key of the analyzer and source Perform error trapping Line 120 Press ENTER to continue Line 130 Set the analyzer and source to local mode Perform error trapping Line 140 Press ENTER to continue Perform error trapping Line 150 Preset the analyzer and source Perform error trapping Line 160 End program execution Line170 Define a subroutine that waits for the ENTER key to be pressed Line 180 Return from the subroutine Running program 1 1 Press ALT F N on the computer This clears the QuickBASIC screen 2 Typeinthe program Press ALT D
339. nd protect the circuitry of the test equipment AVOID ELECTROSTATIC DISCHARGE Weara grounded wrist strap Use an anti static mat Ground yourself to discharge static electricity Also discharge all devices before connecting them Figure 2 Electrostatic Discharge Electrostatic Discharge VISUAL INSPECTION inspect all connectors carefully before every connection Look for metal particles scratches dents Never use a damaged connector Visual inspection and if necessary cleaning should be done every time a connection is made Metal and metal by product particles from the connector threads often find their way onto the mating plane surfaces when a connection is disconnected and even one connection made with a dirty or damaged connector can damage both connectors beyond repair Magnification is helpful when inspecting connectors but it is not required and may actually be mis leading Defects and damage that cannot be seen without magnification generally have no effect on electrical or mechanical performance Magnification is of great use in analyzing the nature and cause of damage and in cleaning connectors but it is not required for inspection Obvious Defects or Damage Examine the connectors first for obvious defects or damage badly worn plating deformed threads or bent broken or misaligned center conductors Connector nuts should move smoothly and be free of burrs loose metal particles and
340. nly with 8757 SYSTEM INTERFACE connected and active t iw te 11 Tablel Function Select Commands 5 of 6 HP IB N Save Recall SVn 2 Registers RCn 2 ERO 1 Save front panel settings in register n n from 1 to 9 Note that registers 1 to 4 also retain title channels 1 and 2 limit line information and channels 1 and 2 trace memories Recall front panel settings from register n n from 1 to 9 Erase all save recall registers Instrument IP 1 Presets the HP 8757C E and the instruments connected to the 8757 Preset SYSTEM INTERFACE Front Panel MM 1 Display the Channel Menu Menus MUO 1 Display the Measurement Menu Softkeys MUI 1 Display the Display Menu MU2 1 Display the Scale Menu MU3 j Display the Reference Menu MU4 1 Display the Cursor Menu MUS 1 Display the Average Menu MU6 1 Display the Calibration Menu MU7 1 Display the Special Menu MU8 1 Display the System Menu SKq 2 Select Softkey q qis from 1 to 8 Equivalent to manually pressing the softkey Display Color Control Adjust the overall display brightness Values for d can be defined by the user See the Operating Reference for more information Set defauit colors Set monochrome mode Selects channel q as the feature affected by color selection commands found under CLx Valid values for qare 1 to 4 Set labels color Selects background as the feature affected by
341. nsions of microwave connectors are small and some of the mechanical tolerances are very precise on the order of a few ten thousandths of an inch Seemingly minor defects damage and dirt can significantly degrade repeatability and accuracy In addition the mating surfaces of most preci sion connectors are gold plated over a beryllium copper alloy This makes them very susceptible to mechanical damage due to the comparative softness of the metals Part One of this Hewlett Packard Microwave Connector Care Manual provides general information that applies to all connector types It gives Hewlett Packard s recommendations on handling and storage of all microwave connectors on visual and mechanical inspection of connectors using a connector gage and on making connections Among the most important general recommendations made in Part One of this manual are these e microwave connectors must be kept clean and the mating plane surfaces protected from harm during storage never store connectors loose in a box or a drawer connectors should be inspected visually before every connection and damaged connectors discarded immediately connectors should be cleaned first with compressed air if a solvent must be used pure liquid Freon is the best solvent should never be sprayed into a connector use a cotton swab or lint free cloth and the least amount of solvent possible avoid wetting plastic support beads with solvent connectors sh
342. nspect all male SMA connectors mechanically using a precision connector gage and for misalignment or burrs on the male contact pin Do not use any connectors that are out of specification or damaged SMA connectors Figure 21 are inexpensive 3 5mm connectors in which a solid plastic dielectric is used between the center and outer conductors SMA connectors are not precision devices They are not designed for repeated connections and disconnections they wear out quickly and they are very often found upon initial assembly to be out of specification even before they have been used They are used most often as one time only connectors in internal component assemblies and in similar applications in which few connections or disconnections will be made Specifications and manufacturing tolerances of SMA connectors are fairly loose This helps keep their cost low but it also makes SMA connectors potentially destructive both to one another and especially to any precision 3 5mm connectors with which they might be mated See the discussion later in this section before mating SMA and precision 3 5mm connectors SMA and Precision 3 5mm Connectors SMA and Precision 3 5mm Connectors 53 54 SMA Connector Problems Two types of problems are the most common with SMA connectors problems due to the solid plastic dielectric problems due to SMA male pins Dielectric Protrusion Some SMA connector specifications allow protrusion of the so
343. nt Input C absolute power measurement Input R absolute power measurement External ADC Input AUX voltage measurement Measure Ratio ratio measurement A C ratio measurement A R ratio measurement B A ratio measurement B C ratio measurement B Rratio measurement C A ratio measurement C B ratio measurement C R ratio measurement R A ratio measurement R Bratio measurement R C ratio measurement Display measurement data Display memory data Display normalized data measurement memory Display hold on off of the active trace Store measurement data into memory Store normalized data measurement memory into memory Display trace data a log magnitude format Display trace data in a Standing Wave Ratio SWR format Display Trace Data Autoscale the trace on the CRT Set scale per division to d where d is for dB dBm 20 10 5 2 1 0 5 0 2 or 0 1 for SWR 10 4 2 1 0 4 0 2 0 1 0 04 or 0 02 for Volts 5 2 5 1 0 5 0 25 0 1 0 05 or 0 025 Reference MR Level Marker Reference Level Moves the cursor or active marker if no cursor and trace to the reference line RLd Set Reference Level to d d must bein the range of ratio measurement 90 to 90 dB normalized measurement 90 to 90dB power measurement 20 to 70 dBm SWR measurement 1 0 to 37 0 SWR voltage measurement 10to 10V normalized voltage measurement T20to 20V STd 3 Set Reference L
344. nter Conductor Collet Removal and Insertioli uu e ovS EP ERG Ern Ee p S54 35 Figure 15 Gaging Precision 7mm Connectors 38 Figure 16 Seating Precision 7mm Connectors 41 Figure 17 Precision 7mm Adapters 43 TABLES PART ONE PRINCIPLES OF PART TWO CONNECTOR TYPES CONNECTOR CARE Type N Connectors Table 1 Recommended Connector Gages 25 Table 2 Torque Wrenches 055 29 Dd APER 46 ii Contents General Introduction Recent advances in measurement capabilities have made connectors and connection techniques more important than ever before Damage to the connectors on calibration and verification devices and on test ports cables and other devices also represents an increasing burden in downtime and expense This publication the Hewlett Packard Microwave Connector Care Manual is an inclusive general reference Its purpose is to help you get the best performance from ail coaxial microwave connectors regardless of type or application to know what to look for when cleaning and inspecting them in order to preserve their precision and extend their life and to make the best possible microwave connections improving both the accuracy and repeatability of all of your measurements saving both time and money Part One provides general information that applies to all connector types and gives Hewlett Packard s recommendations on handling and storing microwave connectors preventing electrostatic
345. ntered as 0 dB or 0 dBm The limit line to memory functions cannot be used with SWR display mode e dBA PLOT ENTRIES sends the limit line frequency and amplitude values to the plotter in FLAT LIMIT lets you define a fiat limit that is a constant value between two frequency points tabular format m e e a a P ANT rd arr E Ia ert aree rarae errare rie rnb NM pma mamans eura Penne RENI Naaman rtr err emer enr rn Petri AA BEP Atay aru err amare rrt un morena 28 Operating Reference HP 8757C E otras ae ope er nO ee eS ey PRINT ENTRIES sends the limit line frequency and amplitude values to the printer in tabular form PRIOR MENU returns the previous limits menu DONE is used to terminate limit line data entry Tor the active channel It also returns the previous menu special functions LIM LINS ON OFF is the last softkey in the special functions menu Ittoggles the limitiines on and off for the active channel When limit lines are turned on each limit line segment becomes visible onthe CRT as itis entered You can turn limit lines on even when no limit lines have been entered if you do the CRT will show a PASS condition for any measurement data A M M Ar er er HP 8757C E Operating Reference 29 ENTRY
346. number xx x i e 03 0 for revision 3 0 Output Identity NOTES D ASCII digit B 8 bitbyte comma EOI Endor Identity HP IB line true cr carriage return lf line feed 17 Table4 CRT Graphics Commands 1 of 2 HP GL Subset Note All Graphics Commands must be terminated with a semicolon or a linefeed the character carriage return is ignored HP IB Command Command Description Default sets monochrome default values DI 1 0 SI Q 14 0 17 DI run rise Absolute Character Direction run rise allowable values are 1 0 Odegrees default 0 1 90degrees 1 0 180 degrees 0 1 270 degrees LB text ETX Label text Character set is shown in table 5 HP 8757C E Modified ASCH Character Set Before labeling text move the pen to the appropriate x y coordinate using the PU and PA commands The text will be plotted with the lower left corner of the first character starting at the existing pen position The pen stops at the lower left corner of the next character space Output the current P1 and P2 positions P1 0 0 P2 2924 2047 The graphics display units GDU s define the plotting area on the CRT The coordinates of the full plotting are are 0 0 for lower left 2924 2047 for upper right The coordinates for the trace graticule are 214 150 for lower left 2500 1814 for upper right 1 1 2 2 Plot Absolute x and y are integers and are in Graphic
347. o 29 decimal followed by ENT using the keypad Avoid the use of address 21 most HP IB controllers use this address and any address used on the 8757 SYSTEM INTERFACE analyzer CRT source plotter printer disk drive The new address is retained in non volatile memory until changed by the operator However should battery power to the non volatile memory be interrupted the HP IB address will default to 16 decimal The default addresses associated with the analyzer are listed in Passthrough Secure frequency mode The BL1 programming code blanks the frequency labels of the analyzer and source and places the HP 8757 in secure frequency mode Once in secure frequency mode you cannot restore frequency labels for the existing configuration Fre quency labels can be restored with a PRESET IP command however your frequency settings will be reset Do not confuse this programming code with the BL5 programming code which blanks the entire screen and may be restored Tablel Function Select Commands 1 of 6 HP IB TET D Action Command Syntax escription Channel Channel 1 on and the active channel Selection 2 Channel 2 on and the active channel C3 Channel 3 on and the active channel C4 Channel 4 on and the active channel CO Turns the currently active channel off Measure IA Input A absolute power measurement Power Voltage IB Input B absolute power measureme
348. o use the sweep hold mode modify line 100 to SW2 and delete lines 120 and 130 The program will wait at line 140 until the 10 sweeps are completed Whenever practical use the service request interrupt to sense the end of a TAKE SWEEP command In fact you can use the time to do plotting or printing of data instead of sitting in a loop Service requests are also useful for other events as demonstrated by the next program Program 8 programming the softkeys The analyzer has eight screen labeled softkeys that make your measurements faster and easier Under HP IB control you can re label the softkeys with any annotation and sense 200 when they are pressed Use the softkeys to branch to special measurement pro grams By making full use of the softkeys your automatic system may not need a normal computer keyboard at ali making it as easy to use as a manual instrument Program 8 listing 10 PRINTER IS 1 20 ASSIGN Sna TO 716 30 ABORT 7 40 CLEAR Sna 50 OUTPUT Sna IP 60 OUTPUT Sna CS 8 70 ON INTR 7 GOTO Srq__recv 80 OUTPUT Sna WKI CAL 1 90 OUTPUT Sna WK2 TEST 1 100 OUTPUT 5Sna WK3 CAL 2 110 OUTPUT qgSna WK4 TEST 2 120 OUTPUT Sna WK8 ABORT 130 Wait srq 140 ENABLE INTR 7 2 150 GOTO 150 160 Srq_recv 170 Stat SPOLL Sna 180 OUTPUT 5 OK 190 ENTER Sna Key code SELECT Keycode 210 CASE 32 220 PRINT Calibration 1 230 CASE 8
349. olled through the passthru address 19 is the source Line100 Command the source to set a start frequency of 0 GHz and a stop frequency of 20 GHz 110 Set the cursor to the maximum point on channel 2 and command the analyzer to output the cursor s value and position Line 120 Line 130 Read the value and position of the cursor On the computer CRT print the value and position of the cursor Line 140 Get the new cursor position from the user Input should be between 0 and 400 Line 150 Set the cursor to the new cursor position chosen by the user The INT function truncates instead of rounding so add 0 5 to the cursor position before making it an integer Line 160 Command the analyzer to output the cursor s value and position Line 170 Read the value and position of the cursor at its new position Line 180 Print the cursor s value and position on the computer CRT Line 190 Get the new cursor frequency from the user It must be within the frequency range of the sweep selected Line 200 Calculate the position of the cursor from its frequency and the start and stop frequencies of the current measurement Line210 Set the cursor to the desired position Line 220 Command the analyzer to output the cursor s value and position Line 230 Read the cursor s value and position Line240 Calculate the cursor s actual frequency from its position and the start and stop frequencies of the current measurement You can easily progr
350. om device to device Therefore before gaging any connector consult the mechanical specifications provided with the connector or the device itself Mechanical Inspection Precision 7mm Connectors n precision 7mm connectors Figure 6 contact between the cen ter conductors is made by spring loaded contacts called collets These protrude slightly in front of the outer conductor mating plane when the connectors are apart When the connection is tightened the collets are compressed into the same plane as the outer conductors For this reason two mechanical specifications are generally given for precision 7mm connectors the maximum recession of the center conductor behind the outer conductor mating plane with the center conductor collet removed and a minimum and maximum allowable protrusion of the center conductor collet in front of the outer conductor mating plane with the collet in place The center conductor collet should also spring back immediately when pressed with a blunt plastic rod or with the rounded plastic handle of the collet removing tool With the center conductor collet removed no protrusion of the center conductor in front of the outer conductor mating plane is ever allowable and sometimes a minimum recession is required Consult the mechanical specifications provided with the connector or the device itself CENTER CONDUCTOR COLLET IN PLACE m p E PRECISION 7mm CONNECTOR E122 KK cx UE OUTER CO
351. on The front panel keys are divided into functional groups CHANNEL FUNCTION ENTRY and INSTRU MENT STATE These functional groups are labeled on the analyzer front panel Look on your analyzer s front panel or figure 1 To find a front panel key description in this reference 1 Look for that key under its functional group label in Contents on the front page of this section 2 Turn to the page number listed for the description To Find a Softkey Description When pressed most of the front panel keys present one or more softkey menus These softkeys expand the analyzer s capabilities without adding additional front panel key complexity To find a softkey description 1 Locate the associated front panel key in Contents on the front page of this section 2 Turnto the page number listed The softkey menu descriptions are included with each front panel key description The softkeys are described in the order in which they appear on the CRT from the top to the bottom Operating Reference HP 8757C E if You Can t Find a Softkey If you are looking for a softkey function and don t know which front panel key presents the softkey menu containing this function 1 Find the page number for the softkey menu structure maps for your analyzer 8757C or 8757E remember they are different in Contents on the front page of this section The softkey menu structure maps show all of the front panel keys and their softk
352. on sequence CAL Accesses calibration menu THRU Sets up calibration remove DUT connect thru STORE THRU Stores calibration in memory of active channel DISPLAY Accesses display menu MEAS MEM Normalizes measurement trace subtracts data stored in memory calibration data from current measurement data Reflection measurement calibration Coaxial scalar systems commonly use a short and open as the calibration standards for a reflection measurement Since either standard reflects all incident power they provide a convenient 0 dB reference Mismatches and directivity in the test setup cause calibration and measurement errors that vary as a function of frequency A test setup with either a short circuit or a shielded open include the same calibration errors 180 out of phase with each other Therefore by aver aging the responses of a short circuit and a shielded open circuit the mismatch and directivity effects will cancel dur ing calibration producing an accurate reflection reference With waveguide scalar measurement systems only a fixed short may be utilized as the calibration standard since it is impossible to create a full reflection open circuit Calibration sequence CAL Accesses calibration menu SHORT OPEN Sets up calibration connect short STORE SHORT Connect open STORE OPEN Stores calibration in memory of active channel Accesses display menu Normalizes measurement trace DISPLAY MEA
353. onnector Care Manual should be followed carefully Type N Connectors Because of their smaller size SMA and precision 3 5mm connectors can be used at higher frequen cies than 7mm connectors can SMA connectors are low cost 3 5mm connectors generally used up to about 23 GHz The name is an abbreviation of the connector type SubMiniature connector type A solid plastic dielectric separates the center and outer conductors Precision 3 5mm connectors also known as APC 3 5 connectors precision air dielectric connec tors that will mate with SMA connectors They offer much greater repeatability of connection than SMA connectors do and for this reason they are widely used on electronic test equipment Precision 3 5mm connectors can be used up to about 34 GHz E Both SMA and precision 3 5mm connectors are sexed connectors The male contact pin slides into the female contact fingers and electrical contact is made by the inside surfaces of the tip of the female contact fingers on the sides of the male contact pin The mechanical specifications for both SMA and precision 3 5mm connectors give a maximum and a minimum recession of the shoulder of the male contact pin and a maximum and a minimum recession of the tip of the female contact fingers behind the outer conductor mating plane SMA CONNECTORS SMA connectors are not precision devices Inspect them and use them carefully with a knowledge of their limitations i
354. oose particles on the connector mating plane surfaces can usually be removed with a quick blast of compressed air This is very easy to do and should always be tried first Clean air cannot damage the connectors or leave particles or residues behind Any source of clean dry low pressure compressed air can be used if it has an effective oil vapor filter and liquid condensation trap placed just before the outlet hose The hose nozzle shouid be grounded to prevent electrostatic discharge and the air pressure set for a very low velocity lt 60 psi High velocity air can cause undesirable electrostatic effects when directed into a connector But the easiest method is to use compressed air actually compressed Freon from a small pres surized can This is available as HP Part Number 8500 2503 and the stream of air can be directed exactly where it is wanted through a plastic not metal nozzle No hoses or other connections are needed Hold the can upright to avoid spraying liquid along with the vapor The liquid propellant will not damage the connectors But rapid vaporization and expansion of the liquid as it escapes from the end of the plastic tube can cool the connector very rapidly The undesirable result is that water vapor from the atmosphere condenses on and inside the the connector and sometimes the interior support bead may be cracked or shift position If liquid is accidentally sprayed onto a connector immediately move the air source
355. or channel 1 and for channel 2 The limit lines consist of upper and lower limits for a frequency or a band of frequencies You can also choose just the upper or the lower limit Turn on ihe limit lines and they are shown on the CRT and the measurement data is compared to the limit lines An out of limit condition is shown with a FA TL message on the CRT below the mode labels area Three types of limit lines are available point flat line and sloped line One limit line can contain up io 12 segments Each segment can be any one of the three types Segments are numbered sequentially when they are entered from the front panel If entered through HP IB segments be entered in random order The CRT prompts you for frequency and upper and lower limits Use ihe numeric keypad to enter the frequency and terminate the entry with the softkey which represents the units x1 Hz kHz MHz GHz Use the numeric keypad aiso to enter the upper and lower limits and terminate the entry with the dBm dB or ENT key If you do not want either the upper or the lower limit press the Bm dB or the ENT key immediately after the prompt Limit lines can be stored only in save recall registers 1 through 4 Limit lines are restri icted io traces with 401 points or fewer Limit entries can be made in dB dBm or SWR depending on the display format In SWR mode however the limits cannot be saved in trace memory Limit entries can also be made in volts
356. or positions some frequencies cannot be set exactly To use more points per trace when using the HP 8757C modify line 80 to be IP SP801 for 801 points Then modify 400 in lines 140 200 and 240 to 800 Program 5 read a single value Measurements often require that a single value be read at a CW frequency particularly when extremely good frequency accuracy and resolution are required The analyzer is able to read and send a single reading of any measurement channel via HP IB to the computer The OUTPUT VALUE OV command operates on the active channel and causes the analyzer to send one reading of measurement data Even when the analyzer is in normalized mode MEAS MEM the OV command sends the measured not the normalized data This command like the OUTPUT DATA command in program 6 can operate with either ASCII or fast binary formats Program 5 listing 10 PRINTER IS 1 20 ASSIGN Sna TO 716 30 ASSIGN Passthru TO 717 40 ABORT7 50 CLEAR Sna 60 OUTPUT GSna IP 70 OUTPUT gGSna PT19 80 OUTPUT Sna SW0 90 Freq 2 100 Freq_step 1 110 OUTPUT Passthru CW Freq GZ SF Freg step GZ 120 OUTPUT gSna 130 FORI 1TO21 140 OUTPUT GSna OV 150 ENTER Sna Value 160 PRINT L Value dB at Freq GHz 170 OUTPUT qPassthru CW UP 180 Freq Freq Freq_step 190 NEXTI 200 OUTPUT Passthru FA2GZ FBAGZ 210 OUTPUT Sna SW1 220 END Program 5 explan
357. ores current CRT graphics to disk This information is stored under the active file titie L ALL stores the instrument state trace measurement and memory normalized trace data only if the current display function is MEAS and CRT graphics to disk in one i STORE TO DISK presents a menu which allows you to store your instrument state trace data operation This information is stored in separate files under the active file title PAM A aUa eR rrt ierat a B HERNAN Ari I MIs a E or ananas eani EM Imma murem Par be A NPY mararmeerver WAH Baer tamm eoa ramener neminem MTL ARITA Mer LIP OIA et vitta 44 Operating Reference HP 8757C E TITLE FILE lets you create a new file tite The current active file title is displayed in the title area on the CRT To create a new file tite first erase the active file title Then enter up to eight characters The new title is shown in the title area as you create it FILE DIRECT shows you the directory of files on the specified disk The directory holds 382 files with 16 files to a page title Make sure that the files you wish to delete are active You have two options SET UP DISK presents another menu that lets you set disk unit and volume numbers initialize disks and to define the format in which to save the data HP 8757C E DELETE FILE deletes files from the directory Pressing DELETE FILE shows you the active file GRAPHIC O
358. ories Supplied 1 0 HP 8757C E General Information HP 8757C E Operating Manual TABLE OF CONTENTS SECTION 1 GENERAL INFORMATION Front Panel Features 4 EGIAN dese oos odia Lagos ane 1 1 CRT Description 5 Analyzer Similarities 1 1 Front Panel Operation 8 Manual Set Organization 1 2 CHANNEL Keys 8 Instruments Covered By Manual 1 3 FUNCTION 10 Safety Considerations 1 3 Adjusting Color quee e eene enne 15 amp aea gt Mees 1 3 HP 8757 Self Calibration 25 Analyzer Description 1 4 INSTRUMENT STATE Keys 31 AC and DC Detection 1 5 Ploting oe eee ete teen 34 Hewlett Packard Interface Bus 1 5 36 8757 System Interface 1 5 Softkey Menu Structure Maps 54 Options Available 1 5 Rear Panel Features 61 Accessories Supplied 1 6 Operators Check 63 Service Accessories 1 6 Equipment Required But Not Supplied 1 7 Firmware
359. orm reflection measurements with the HP 8757C Signal separation Reflection measurements require the separation of the signal incident upon the input of the device from the device s reflected power A signal separator such as a directional bridge or coupler provides a sample of the power traveling in only one direction when it is connected as shown in the fig ure below the reflected power is separated and measured independently of the incident power Many types of direc tional bridges and couplers are available They are differ entiated by frequency range directivity and connector type Device termination Reflection measurements involve only one port of a test device When a device has more then one port it is critical that all of the unused ports are properly terminated in their characteristic impedance e g 50 or 75 ohms High quality loads or detectors with excellent return loss such as the HP 85025D E should be used whenever possible particu larly with low loss devices Otherwise reflections off the unused ports will cause measurement errors Measurement accuracy In reflection measurements the accuracy of the final result is highly dependent on the signal separation devices adapters and the DUT terminations Systematic errors such as the fre quency response of the test setup directivity and mis matches degrade overall measurement accuracy The HP 8757C E s calibration routines can significantly reduce thes
360. ortion of a cali brated trace SYSTEM ADPT NRM ON OFF Displays system menu Activates adaptive normali zation function select prior to changing the frequency settings Activates marker 1 enter the start frequency on the source via the knob above the marker key or the keypad Activates marker 2 enter the stop frequency on the source Activates the source s marker A function displays the amplitude and frequency differences in the mode label area and beneath the grid respectively Displays an expanded trace which is swept from marker 1 to marker 2 changes the source s front panel settings to reflect the new frequency span M1 M2 SHIFT M1 MKR SWEEP n B R Wn 45 2 B FPeM 25 PEE OQ 5i 4 Be 10 0 dB ARF dB i i HOSBAZUUSTUBUUTTY ET STAT 9 24008H KEES For other examples utilizing adaptive normalization refer to the gain compression measurement section or chapter 5 Alternate Sweep Measuring active devices Active devices devices with gain usually require measure ment at varying input power levels a ratio configuration offers the best measurement results Generally the test setup for measuring gain and insertion loss are very similar Although it will be necessary to add attenuators to the measurement system if the input power to the detector exceeds 20 dBm or damage may result When an activ
361. ould be inspected mechanically using a connector gage before being used for the first time and periodically after that in making a connection the connectors should be aligned carefully a preliminary connection made lightly by turning the connector nut only to pull the connectors together and the final connection made using a torque wrench connections and disconnections should never be made by screwing one connector into the other this is extremely harmful and can occur whenever the device body rather than the connector nut alone is turned Part Two of this manual provides detailed information on each main connector type repeating and expanding upon key points presented in Part One Introduction HANDLING AND STORAGE Keep connectors clean Do not touch the mating plane surfaces Do not set connectors contact end down Before storing extend the sleeve or connector nut Use plastic end caps over the mating plane surfaces Never store connectors loose in a box or a drawer Microwave connectors must be handled carefully inspected before use and when not in use stored in a way that gives them maximum protection Avoid touching the connector mating plane surfaces and avoid setting the connectors contact end down on any hard surface Natural skin oils and microscopic particles of dirt are easily transferred to the connector interface and are very difficult to remove Damage to the plating and to the mating plane surfaces oc
362. ource it writes the softkey labels on the analyzer CRT When the first key label is written the analyzer labels it and blanks the other softkey labels Since all labels except softkeys 5 6 and 7 are given new labels softkeys 5 6 and 7 remain blank 4 Press any key on the analyzer except the ABORT softkey Pressing a softkey causes a message to be printed on the CRT of the computer Note that softkeys 5 6 and 7 generate an interrupt even though they weren t labeled No other keys of the analyzer generate an interrupt because of the SRQ mask specified Because the analyzer is in remote mode nothing is changed by pressing its keys 5 Press the ABORT softkey to end program execution In this example the service request mask was set to interrupt the computer whenever a softkey was pressed Another bit in the mask causes an interrupt to be generated when any key is pressed Because the analyzer was left in remote mode it didn t respond to any keys pressed on its front panel In some applications it is useful to put the analyzer into local operation so that it can be controlled from the front panel and still generate interrupts whenever a key is pressed Program 9 CRT graphics For applications requiring diagrams drawings or limit lines the CRT of the analyzer may be written to as if it werea Hewlett Packard plotter By defining the analyzer as the plot device used by the computer you can even use the special plottin
363. p of the female contact fingers and the shoulder of the male contact pin could be less than zero when the connectors are mated Gage Type N connectors carefully to avoid damage As Type N connectors wear the protrusion of the female contact fingers generally increases due to wear of the outer conductor mating plane inside the female connector This decreases the total center conductor contact separation and should be monitored carefully 750 Type N Connectors 750 Type N connectors differ from 500 Type N connectors most signifi cantly in that the center conductor male contact pin and female contact hole are smaller Therefore mating a male 500 Type N connector with a female 75Q Type N connector will destroy the female 75 connector by spreading the female contact fingers apart permanently or even breaking them If both 750 and 500 Type N connectors are among those on the devices you are using mark the 75Q Type N connectors to be sure that they are never mated with any 500 Type N connectors Type N Connectors 45 46 MECHANICAL SPECIFICATIONS OF TYPE N CONNECTORS Type N connectors require a minimum recession of the shoulder of the male contact pin of 0 207 inches and allow a maximum protrusion of the tip of the female contact fingers in front of the outer conductor mating plane of 0 207 inches e Pin depth specifications for 750 Type N connectors are the same as for 500 Type N connectors The connector types differ in the size
364. pe N connectors may be connected finger tight If a torque wrench is used 12 Ib in 136 N cm is recommended SMA 5 8710 1582 56 N cm Use this wrench also when connecting male SMA connectors to female precision 3 5mm connectors Connections of male precision 3 5mm connectors to female SMA connectors can be made with the precision 3 5mm torque wrench 8 Ib in Type N and NMD 3 5 Connectors Note that Type N connectors unlike other connectors do not have wrench flats and thus can only be connected by hand Connect Type N connectors finger tight The same is true of the NMD 3 5 precision 3 5mm connectors used for example on the HP 8513A and HP 8515A test sets and on the HP 85131A B 3 5mm test port return cables These connec tors are also designed to give the correct torque when the connector nut is connected finger tight Excessive Connector Nut Tightness Precision 7mm Connectors Sometimes it is almost impossible to apply torque to a precision 7mm connector without causing the device itself to turn If this occurs clean the connector nut threads carefully and make the connection again If great resistance is still encountered probably the outer nut and the inner sleeve are locking together at the back plane of the connector where the force of the torque is transferred to the inner sleeve Disassemble the connector nut assembly and inspect the interior bearing surfaces for galling of the Stainless steel on these sur
365. peration This information must have been previously stored under the current active file title ALL HOLD loads the files listed in the ALL function above in addition to holding the measurement display This allows archived data to be viewed and plotied The following i display functions are also allowed manually or via HP IB scaling cursor cursor search smoothing data plotting printing channels on off or SWR display when data is stored as SWR All other recall functions remain the same i i NOTE Smoothing will be turned off if the stored file has smoothed data GRAPHIC ON OFF allows you to turn on or off araphics that have been recalled from disk or placed in graphics memory by computer GRAPHIC ON shows graphics and softkey menus and blanks all instrument state and measurement data The current softkey menu remains active on the CRT and all other softkey menus can be accessed A useful application tor this function might be an instrument connection diagram which a user can access at any time during the measurement process GRAPHIC OFF turns oif graphics and returns the instrument state and measurement data IPRIOR MENU returns the previous menu FILE DIRECT shows you the directory of files on the specified disk The directory holds 382 files with 16 files to a page NEXT PAGE shows you successive pages of the directory PREV PAGE shows you previous pages of the dire
366. phics Language HP GL shown in table 4 The analyzer graphics characters used for labeling are shown in itable 5 HP 8757C E Modified ASCII Code Conversion Table These modified ASCH characters are available only when explicitly using the LB command many desktop com puter plotter commands use different character sets The address of the CRT is the analyzer address minus 1 The default address of the analyzer is 16 decimal therefore the default address of the CRT is 15 decimal This example shows how to pass through commands to the CRT with address 15 decimal using the analyzer default address 16 decimal 1 Address device 16 the HP IB port of the analyzer and send the command PT15 2 Address device 17 the 8757 SYSTEM INTERFACE and send graphics commands to the CRT 3 Address device 16 This returns the analyzer to its normal HP IB operation Output data The analyzer has several output modes that allow you to learn or interrogate the instrument state and to output data The fol lowing output modes are available Learn String Interrogate Function m Status Error m Data m Identity The program codes and syntax to enable each function are shown in table 3 Learn string Selected with the OL program code the analyzer outputs a learn string of 150 bytes in length This binary data string completely describes the present instrument state excluding the storage registers trace memo
367. plete all of the sweeps specified by the TAKE SWEEP command have been com pleted When you follow the take sweep command with an output statement such as OUTPUT DATA OD the data is sent immediately not after the instructed number of sweeps The two approaches mentioned overcome this by letting us send the data at the end of the specified number of sweeps not immediately A third approach is to use the sweep hold mode SW2 instead of the non swept mode SW0 In this mode the analyzer will prevent any HP IB operations until the completion of the TAKE SWEEP command 13 Program 7 listing 90 100 110 120 130 140 160 170 180 190 200 220 230 390 430 440 460 470 480 14 AS REM INCLUDE GBSETUP CLS DIM ASCIIDATCO TO 4002 isc amp 7 Sna amp 716 Passthru 717 CALL IOTIMEQUTCIsc amp 102 IF PCIB ERR NOERR THEN ERROR PCIB BASERR CALL IOABORT CIsc amp IF PCIB ERR NOERR THEN ERROR PCIB BASERR CALL IQCLEARCIsc amp 20 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A IP GOSUB IODUTS PT19 GOSUB IGOUTS ST250MS CALL IQOUTPUTS Passthru A LENCA 22 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR A C2C0 IB GOSUB IQOQUTS AS SW0 CS RM1G GOSUB 1000 5 Stat 0 A 7TS10 GOSUB IODUTS DO UNTIL Statt MOD 32 gt 15 CALL IOSPOLLCSna amp Statz IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR LOOP A C10D Max 40
368. pondence refer to the instrument by model number and full serial number installation HP 8757C E Shipment Preparation Instructions If standard analyzer with handles only ship If option 913 with rack mount flanges remove four panhead screws and one rack mount flange per side Reinstall one front handle assembly 3 with four flathead screws per side and ship If the analyzer lacks handles perform step 3 Figure 2 8 Preparation of Instrument for Shipment HP 8757C E Installation 2 15 Figure 2 9 Packaging for Shipment Using Factory Packaging Materials HP 8757C E stallation In 2 16 HP 8757E FIRMWARE REVISION HISTORY This section describes HP 8757E firmware revisions which includes a brief description of the additional features This is only a summary For more complete information refer to the HP Scalar Network Analyzer Operating Manual and Operating Reference Revision 4 0 initial shipment release Revision 4 1 New softkey CSR FMT SWR dB has been added to the CURSOR key menu Corresponding remote commands are FRO for log magnitude and FR1 for SWR This function allows convenient readout of cursor data in SWR standing wave ratio when measuring device match in dB return loss This function is similar in operation to the HP 8757A feature e New softkey PLT BUF ON OFF has been added to the SYSTEM key menu The corresponding remote command is BFm This function enables and disabl
369. pplies only to the active channel The measurement parameter chosen is shown in the mode labels area next to the channel number Pressing PRESET the green INSTRUMENT STATE key presets channel 1 to measure input A and channel 2 to measure input B In the mode iabels area an is shown nextto CHt anda B nextto CH2 The measurement menus are layered Pressing MORE accesses the next menu PRIOR MENU returns the previous menu AUX selects a voltage input from the rear panel ADC IN 10 to 10 V connector This voltage is shown on the active channel instead of data from a single or ratioed detector input This function can be used to observe the control voltage input to a voltage controlled device HP 8757C E Operating Reference 1 12 DISPLAY DISPLAY MENUS HP 8757C FUNCTION c cJ Figure 9 DISPLAY Key and Display Menus The DISPLAY key presents the display menu figure 9 which lets you control how the measurement data is processed and shown on the CRT This menu lets you show the measurement the data in memory of the active channel or the difference between the two It also lets you enter the measure ment or the measurement minus memory into memory Remember that selection of any of these softkeys engages that function for the active channel only HP 8757C ONLY This menu also lets you define the colors used on the CRT attributes such as the grid the channel measurement traces
370. printer Print all to color printer except softkeys and CRT graphics Passthrough address set to d R A ratio measurement R Bratio measurement R C ratio measurement Recall register Reference level set tod Service request mask set to d Reference position set to vertical division q Restart averaging Set cursor to horizontal position d Scale per division set to d Store all instrument information to disk in file Store CRT graphics to disk in file Store data trace to disk in file Store instrument state to disk in file Store memory trace to disk in file Store normalized trace to disk in file Select softkey q q 1 to 8 Cursor search left Store measurement into memory Store normalized data measurement memory into memory Smoothing set to d of frequency span Number of points set to d d 101 201 401 801 1601 Cursor search right Cursor search value set to d Reference level step size set to d Specify custom plot according to d Save registern Non swept mode non swept operation Swept mode normal swept operation Sweep hold mode non swept mode with HP IB bus hold off until completion of TSd Continuous Temperature Compensation on off Title for file Take d sweeps then hold display Step up increment Write softkey label Write to channel memory Write title s isan ASCH string of up to 50 characters External detector cal viaue for detector A External detector cal val
371. program listing 3 Anexplanation of each program line 4 Detailed instructions for operating the program When you finish all of the example programs you will have a good idea of the power of the HP 8757C E when used in an automatic system 1 HP 8757C only 2 HP 8757C Option 001 only Program 1 remote local and local lockout The analyzer may be used with the front panel local oper ation or programmed via HP IB remote operation The programmer of the instrument system has control over the operation of all instruments in the system When the computer first addresses an instrument the instru ment is placed in a special remote operating mode called remote mode When in remote the instrument does not respond to its front panel except for the LOCAL key LOCAL when pressed cancels the remote mode and allows the instrument to be used with its front panel The computer can also return the instrument to local opera tion To do so the computer sends a special command that forces the instrument to go to local mode Occasionally the programmer of an automatic system needs to prevent the instrument operator from returning the instru ment to local operation via LOCAL When the local lockout function of the computer is used the instruments are prevented from exiting remote mode even when LOCAL is pressed Frequently the programmer needs to place the instruments connected to the computer into a known st
372. propriate key to exhibit the parameter in the active entry area The HP 8757E utilizes a monochrome display The HP 8757C offers a color display that may be customized to the user s particular color preferences A monochrome dis play mode is also available at the touch of a softkey in the DISPLAY menu Mode labels This area of the CRT is used to show the current status of various functions for the activated channels an example is shown below The following table lists the status symbol notations and their meanings Measurement Cursor or Marker Value Status Symbols Reference Level Value The trace displayed represents the subtraction of the stored data from measured data The trace displayed represents stored data Trace smoothing is on Trace averaging is on Adaptive Normalization is on HP 8757C only Adaptive Normalization is on but uncalibratec the frequency span has been increased beyond the original calibration span Scale per Division M Mode Labeis Title i Active Entry Area STRT 8 2400GHz 232 ZSMHz STOP Cursor A or Marker A Frequencies Frequency Labels Channel selection Many measurement and display functions are independently selectable for each channel To modify the parameters of a particular trace first select that channel making it the active channel then make the desired measurement choices The mode label area of the act
373. put Learn string Initialize disk format Instrument preset Input R absolute power measurement External ADC input AUX voltage measurement Erase limit lines for active channel Load instrument information file from disk Load CRT graphics file from disk Load data trace file from disk Load instrument information file from disk and place instrument in hold mode Load instrument state file from disk Load memory trace file from disk Enter limit test flat line data Store lowerlimitlineinto memory Revision 3 1 or above HP 8757C revision 4 1 or above for an HP 8757E i HP 8340 HP 8341 HP 8360 only with 8757 SYSTEM INTERFACE connected active 6 Revision 3 1 or above foran HP 8757C 4 ee Jo HP 8757C onl HP 8757C Option 001 only detector C Limit line funcnons valid only for channels i or 2 HP 8757C only Revision X 1orabove foran HP 8757C Table9 Alphabetical Listing of HP 8757C E Programming Codes 2 of 2 Enter limit test point data Enter limit test sloped line data Limitline test on off Store upper limit line into memory Display normalized data measurement memory Modulation on off Display measurement data Display the channel menu main menu Display normalize
374. quencies Line 190 Get start frequency from user Line 200 Get stop frequency from user Line 210 Set start and stop frequencies of source to those given by the user Line 220 Exit passthru mode by addressing the analyzer Line 230 End program execution Line240 Define a subroutine that outputs commands to the analyzer Line 250 Perform error trapping Line 260 Return from the subroutine Line 270 Define a subroutine that outputs commands to the source through the passthru address of the analyzer Line 280 Perform error trapping Line 290 Return from the subroutine Running program 3 1 Clear the computer CRT and type in the program 2 Press ALT IR S on the computer to run the program 3 The computer presets the analyzer and the source reads the start and stop frequency of the source and displays it on the CRT of the computer At preset the source defaults to the full frequency range of the plug in The values read represent the frequency limits of this plug in When the computer stops it displays the prompt Start frequency GHz Enter a start frequency in the frequency range of the plug in and press ENTER 4 The computer displays the prompt Stop frequency GHz Enter a stop frequency in the frequency range of the plug in but higher than the start frequency and press ENTER 5 The computer sets the start and stop frequency of the source to those you entered The analyzer immediately begins sweeping the frequency r
375. r above foran HP 8757C revision 4 1 or above for an HP 8757E 13 Table 2 HP IB Only Functions 1 of 2 HP 1B Display No blanking restore CRT to normal mode Blanking Blank only the frequency labels Blank all labels on the CRT Blank only the active channel trace Blank only the softkey labels Blank all of the CRT exceptuser graphics Blank only the user title Blank only the mode labels Blank only the active entry area Blank only the limit lines Blank ail of the CRT except user graphics and softkeys Status Clear Status bytes 1 and 2 Bytes RMd Set Request Mask of status byte 1 to d dis decimal integer from 0 to 255 Format Format Data ASCII all successive data transfers are made in an ASCH Data format Data is transferred in DD DDD format where D is an ASCII digit j o Res ee oe FD2 1 Format Data Extended ASCII all successive data transfers are made in an extended ASCII format Data are transferred in DDD DDD format where D is an ASCII digit FD1 1 Format Data Binary all successive data transfers are made in a binary FD3 format FD1 is for HP BASIC MSB first FD3 is for PC format files LSB first Two bytes are transferred the value of which is scaled between the limits shown below normalized normalized ratio power SWR voltage value meas meas meas meas meas meas om nee et 6 CE
376. r consumption is approximately 155 volt amps Make the correct line voltage and fuse selection before connecting line power to the instrument Line Voltage and Fuse Selection Figure 2 1 shows the line voitage selection card and fuse location in the power line module on the rear panel of the analyzer Select the iine voltage and fuse as follows 1 Measure the AC line voltage 2 Onthe instrument rear panel power line module select the line voltage 100 120 220 or 240 volts closestto the voltage you measured in step 1 The available line voltage must be within 10 of the line voltage selection as shown in table 2 1 If not use an autotransformer between the power source and the analyzer 3 Table 2 1 Line Voltage and Fuse Selection Measured PC Selector AC Line Voltage Board Position 90 to 110 volts 100 108 to 132 volts 120 198 to 242 volts 220 216 to 264 voits 240 Install the correct fuse in the fuse holder The required fuse rating for each line voltage is shown in table 2 1 and also below the power line module on the rear panel of the analyzer Additional fuses are available from Hewlett Packard See Replaceable Parts Installation HP 8757C E Receptacle for primary power cord SELECTION OF OPERATING VOLTAGE PC selector board shown positioned for 115 120 Vac power line e 1 Slide open power module cover door and pull fuse pull lever to left to remove fuse 2 Pull out volta
377. r normal use because they will accommodate most color deficient vision and they provide a suitable contrast that is easy to view for long periods of time You may choose to change the default colors to suit environmental needs individual preferences or to accommodate color deficient vision The easiest way to change a color on the CRT is to choose a color from the color list The color list is a selection of 7 factory defined colors You can use any of these colors for any of the 8 CRT attributes The following is a list by softkey of these CRT attributes CHAN 1 COLOR CHAN 2 COLOR Channel 1 2 3 or 4 measurement trace mode labels CHAN 3 COLOR limit lines and reference level marker CHAN 4 COLOR GRID CRT grid BACKGROUND CRT background WARNING Warning messages LABELS Softkey labels status line frequency labels and title adjust the colors such that you cannot discern an attribute against the background such as red warning labels against a red background The softkey labels however will always be visible Figure 10 shows the color adjustment softkeys in the display menus HP 8757C f deus GRTNESS COLOR SRTNESS isi E pos PLAY i pup BACK BLACK COLOR TOPICS COLORS GROUND R8 es CHAN d WARNING YELLOW TNT coLoni CHAN 2 LABELS BLUES COLOR 1 J CHAN 3 PALMON COLOR Hot ADIIST pere CHAN yh RED D
378. r with a compatible disk drive can be used The software provided with the HP 11613 includes both 3 5 inch and 5 25 inch formats Follow the instructions provided with the calibrator Where a DVM is listed use a digital voltmeter with at least 4 5 digits of resolution except during adjustment of the A4 board where 5 5 digits are required Notes on Re calibration e Ifthe A1 A2 A5 A11 A13 or A14 assemblies are replaced perform no adjustments e ifthe A4 A7 A9 or A10 assemblies are replaced regenerate the cal constants with the HP 11613A B e Ifthe A12 power supply is replaced adjust all supply voltages Adjust all power supplies within 0 05 volts of their nomina voltages Adjust the 5 voit supplies to 5 1 volts e Replacing the A15 display requires no adjustments although the intensity levels may vary slightly from the previous display ifthe A4 ADC board is replaced check the DAC gain adjustment with a DVM Use this following procedure after the analyzer has warmed up In Case of Difficulty HP 8757C E 1 Connect DVM LO to A4TP4 AGND and DVM HI to A4TP2 DAC Both test points and A4R6 are accessible without removing the A4 assembly cover 2 Presetthe analyzer 3 Note the maximum SWEEP DAC VOLTAGE approximately 0 0 V indicated on the DVM by pressing SYSTEM MORE SERVICE 4 ADC MORE CHANNEL VOLTS CHANV OTHER SWP DAC MAX 4 Note the minimum SWEEP DAC VOLTAGE on the DVM by press
379. race points use the TRACE POINTS softkey in the system menu Table 2 Minimum Sweep Time Versus Number of Points Number of Minimum Sweep Time ms 40 50 60 70 1 HP 8757C only HP 8757C E Operating Reference 13 Vertical Display Data Resolution Memory data is always stored at the highest resolution regardless of f 5 the displayed resolution scale per division or reference level Viewing normalized dB data will reduce resolution by one half Vertical display resolution and display range for the various display modes are shown in table 3 Table 3 Display Ranges and Vertical Resolution Display Vertical Display Display Range Resolution 70 to 20 dBm 0 003 dB 90 to 90 dBm 0 006 dB 1 0 to 37 0 See graph below 10 to 10 V 1 0 01 dB for display cursor 2 20to 20 V for normalized AUX SWR is calculated from dB data SWR resolution varies with the SWR being measured 2 z2 0 Qr ko 25 c o gt 0 Operating Reference HP 8757C E oa E ENE EA R O E i Ei wel hea oda HP 8757C ONLY HORE TENES oo aber tie acta Se aaa UN ADJUSTING COLOR This procedure explains how to adiust the colors on your CRT The default colors in this instrument have been scientifically chosen to maximize your ability to discern the difference between the colors and to comfortably and effectively view the colors These colors are racom mended fo
380. ransistor test fixture with these test sets the adapters in the HP 85130A special 3 5mm F to 7mm adapter kit should be used at the test ports instead of any other adapters This kit has been developed expressly for this single purpose The adapters in the HP 85130A special adapter kit have two special features 1 the 3 5mm side is a special NMD 3 5 connector designed specifically to mate with HP 3 5mm test ports and 2 the 7mm side has a center conductor setback that is the same as the setback on HP 7mm test ports Thus the 7mm interface that results is the same as is found on test sets with 7mm connectors Other adapters may be used at non port connections to connect ordinary 7mm devices to ordinary 3 5mm devices Precision 7mm Connectors 7mm to 3 5mm SMA COMPATIBLE ADAPTERS maie precision 3 5mm female precision 3 5mm precision 7mm precision 7mm HP Part Number 1250 1746 HP Part Number 1250 1747 4 slot center conductor collets HP Part Number 85052 60004 HP Part Number 85052 60003 6 slot precision center conductor collets 7mm to Type N ADAPTERS male Type N femaie Type N precision 7mm precision 7mm HP Part Number 85054 60009 HP Part Number 85054 60001 Figure 17 Precision 7mm Adapters Precision 7mm Connectors 43 44 Type N Connectors Type N connectors are relatively inexpensive rugged 7mm connectors developed for severe operat ing
381. ransmis sion and reflection measurements The Remote Operation subsection contains programming guides with example programs and a listing of commands that are compatible with the analyzer In Case of Difficulty explains what to do when a problem is encountered with the analyzer it gives suggestions for minor problems that do not involve defects in the internal circuitry If a problem is encountered that is not solved using any of these suggestions go to section 8 of the service manual for troubleshooting information Microsoft is a U S registered trademark of Microsoft Corp HP 8757C E Operation 3 1 HP 8757C FIRMWARE REVISION HISTORY This section describes HP 8757C firmware revisions which includes a brief description of the additional features This is only a summary For more complete information refer to the HP 8757C E Scalar Network Analyzer Operating Manual and Operating Reference Revision 3 0 Initial shipment release Revision 3 1 New softkey CSR FMT SWR dB has been added to the CURSOR key menu Corresponding remote commands are FRO for log magnitude and FR1 for SWR This function allows convenient readout of cursor data in SWR standing wave ratio when measuring device match in dB return loss This function is similar in operation to the HP 8757A feature e New softkey PLT BUF ON OFF has been added to the SYSTEM key menu The corresponding remote command is BFm This function enables and disables
382. raphics The file name associated with each of the sub files is displayed on the left side of the screen as shown in the example below Selecting any of the sub files accesses all or part of the file depending on what option is chosen from the LOAD FR DISK menu TEST2A ACTIVE FILE TITLE NEXT PAGE FILE TITLE DESCRIPTION NUM OF POINTS pn ED XX DC NM EN ED M CE PREV TEST1A BINARY Instrum State PAGE TESTIA BINARY Measurement Chan 1 401 TESTIA BINARY Measurement Chan 2 401 TESTIA BINARY Memory Chan 1 401 TEST1A BINARY Memory Chan 2 401 TESTIB BINARY Instrum State SELECT TESTIB BINARY Measurement Chan 1 801 TITLE TESTIB BINARY Measurement Chan 2 801 TESTIB BINARY Memory Chan 1 801 TEST1B BINARY Memory Chan 2 801 b TEST2A BINARY instrum State TEST2A BINARY Measurement Chan 1 1601 TEST2A BINARY Memory Chan 1 1601 END OF DIRECTORY PRIOR MENU Sample file directory The following sequence demonstrates how to store and retrieve data using and external disk drive SAVE TITLE FILE ERASE TITLE Accesses the storage menu Accesses the title file menu Allows the entry of a new file name Selects the letter at the cursor on the display use the front panel knob to move the cursor up and down the alphabet Terminates the title selection process returns the user to the save menu Initiates the external storage function Stores all the displayed information the user may choose to store only a portion
383. rapping Clear the HP IB interface of the HP 8757C E Perform error trapping Preset the analyzer and blank all the CRT display except the softkeys Define the CRT graphics as the target of passthru commands The graphics address is always one less than the analyzer s HP IB address Erase all graphics pages Turn graphics page 1 on to ensure that the graphics start in it Select to plot with pen 6 the lowest intensity for the analyzer CRT Repeat a loop 25 times to draw vertical part of the grid Draw a vertical line down the CRT screen End of the loop Line 150 Line 160 Line 170 Line 180 Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260 Line 270 Line 280 Line 290 Line 300 Line 310 Line 320 Line 330 Line 340 Line 350 Line 360 Line 370 Line 380 Repeat loop 20 times to draw horizontal part of the grid Draw a horizontal line across the CRT End of the loop Select to plot with pen 8 the brightest intensity for the analyzer CRT Move the pen to title the display Specify the width and height of each character indicate what the title is terminate the title with an end of text character Move the pen to label the device under test Specify the width and height of each character indicate what the title is terminate the title with an end of text character Move the pen and draw the outline of the source Draw the plug in of the source Move th
384. rce Line 110 Put the analyzer in non swept mode This step is necessary to read single values After receiving this command the analyzer stops updating its display Line 120 Define a start frequency for further measurements in GHz Line 130 Define a frequency increment in GHz Line 140 Put the source into CW mode at the start frequency and set its frequency step size to that of the frequency increment Line 150 Command the analyzer to measure reflection input A on channel 1 This statement also causes the analyzer to exit passthru mode Line 160 21 measurements at equally spaced CW frequencies Line 170 Command the analyzer to send the current reading of channel 1 the active channel to the computer The reading is taken immediately Line180 Read the value In this instance no format has been defined so the default format of ASCII is in effect Line190 Printthe measurement number the reading and the frequency on the computer CRT Line 200 Command the source to increment the CW frequency by the step size set earlier line 110 This is a very fast way of setting a series of equally spaced frequencies Line210 Increment the variable that contains the current frequency This variable is only used for printing the current frequency at each iteration of the loop Line 220 Line 230 End of the loop Command the source to sweep from 2 to 4 GHz The source exits CW mode and returns to start stop mode
385. rea The information saved includes the current front panel settings of the analyzer and source trace memory and titles The memory trace is saved at 401 points regardless of the number of points selected for the measurement HP 8757C E Operating Reference 43 HP 8787 ONLY 7 Limit lines can be saved in registers 1 through 4 oniy The SAVE key also presents the save menus which allow you to store data to disk You can store the instrument states measurement data data in memory and CRT graphics to a disk on a drive connected to the system interface The instrument state information includes front panel settings for the analyzer and source label information LABELS ON OFF FRQ LBL OFF TITLE ON OFF limit lines and color selection if you load the instrument states for an analyzer and source combination into an analyzer with different source the original source instrument state will be applied to the new source The new source will clamp frequency and power at its extreme limits if needed Table 6 is a list of the source settings that are saved on disk Before you store anything to a new disk you must initialize the disk You must also identify the disk unit where the disk resides and the disk volume number of a hard disk drive See SET UP DISK to accomplish these tasks SAVE REGISTR provides the same save to analyzer register function that i
386. reference level to 10 dB RL 10 and set the scale per division to 0 5 dB SD0 5 Inputsyntax 4 function code followed by a string of bytes or characters function code string terminator s An ASCII string of characters or a sequence of 8 bit binary bytes the length of which is unique to the particular Write softkey 1 with the label TEST1 WK1 TEST1 and write a title onto the CRT which says PASSBAND Programming commands may be sent as upper or lower case ASCII characters Spaces unnecessary signs leading Zeros carriage returns cr and unnecessary terminators are ignored by the analyzer The parity bit the eighth bit MSB ofall ASCII coded characters will be ignored Any alphanumeric sequence which is not a recognized HP 8757C E command will be noted on the CRT in the active entry area as UNKNOWN CMD followed by the last one or two characters received by the analyzer over HP IB The analyzer will not lock out further HP IB traffic and will execute any subsequent valid command Further a syntax error service request SRQ will be output if that SRQ bit has been enabled in the request mask see Service Request and Status Byte If there are many errors in the alphanumeric sequence only the last error is displayed in the active function area Programming data See table 1 for HP IB programming commands which control the analyzer 1 HP 8757C only 2 HP 8757C Option 001
387. resents the sweep mode menu This menu is used to specify the type of sweep supplied by a source not compatible with the 8757 system interface or to toggle on and off the 8757 system interface NONSTD ON OFF enables the analyzer to track a sweep ramp other than the expected 0 10 volt sweep ramp The nonstandard sweep must be within the 0 10 volt range See Product Note 8757 5 for a more detailed description of this mode If a sweep in excess of 10 volts is used the A4 ADC assembly must be modified to accept it See section 8 of the service manual for instructions To use nonstandard sweep mode disconnect the POS Z BLANK the STOP SWEEP and the 8757 SYSTEM INTERFACE connections to the source Only the SWEEP IN should be connected The number of trace points selected using the TTRACE POINTS function is still active for nonstandard sweep mode CW ON OFF is used with a source that is not compatible with the 8757 system interface This function allows the display to be continuously updated when the non compatible source is in CW mode with no sweep ramp applied to the analyzer With CW ON the analyzer provides its own cont nuous internal horizontal display update so that any stable input will be shown asa straight line CW ON is also used if the source is 8757 system interface compatible This function is selected automatically when the source is in CW mode or toggling to CW ON will engage the source CW mode MANUAL ON OFF toggles on an
388. ries detectors operate in AC or DC mode When the analyzer is in DC mode the detectors chop the signal after detection to provide the 27 778 kHz signal that the analyzer processes The receiver circuitry is identical in both modes The HP 8757 DC detection process offers the speed advantage of AC detection since the receiver is not limited by the settling time of the log amplifiers at low power levels The following figure presents a comparison of the detection processes for AC and DC modes 1 AC detection 2 DC detection Source 2 HP 85025B Detector Squarewave JUL DC Voltage Using AC detection The HP 8757C E receiver the log amplifiers in the ana lyzer effectively functions like a tuned AC voltmeter operating at 27 778 kHz In many applications such as measurement of high gain limiting amplifiers noise will be present along with the desired signal being measured This type of interference can reduce the effective dynamic range of the measurement system by raising the noise floor In AC detection mode the analyzer is sensitive only to the signals that have the appropriate square wave modulation Since only the desired signal is modulated at the source the noise and other non modulated RF signals are ignored resulting with a true representation of the performance of the device under test Temperature changes can have a dramatic effect on measure ments in DC mode since they
389. roller monitoring source functions This interface provides frequency annotation on the CRT display full use of all source marker modes and control of the analyzer and source preset and save recall functions Also it facilitates full use of the source sweep functions such as CW continuous wave alternate and power sweep modes If the DUT is sensitive to the input power level the power should be measured at the test port of the power splitter or directional bridge To accomplish this the device should be removed and the detector attached directly to the test port then the power level on the source should be adjusted until the desired RF power level appears on the analyzer display Typically when the system is connected as in the previous figure there is a 12 to 14 dB loss in power from the power splitter and directional bridge between the output of the source and the output of the test port Once the power level has been set reconnect the DUT Step four perform calibration Accuracy in network analysis is greatly influenced by factors external to the network analyzer Parts of the measurement setup such as directional bridges detectors and adapters all introduce variations that can distort the actual performance of the DUT These errors are assumed to have a cummula tive effect thus increasing the overall uncertainty of the measured data Since scalar network analyzers measure the magnitude only response of the DUT or cali
390. ront panel are used to control system functions that are not channel specific but apply to the entire instrument state HP 8757C E Operating Reference 31 SYSTEM SYSTEM MENUS INSTRUMENT STATE SYSTEM RECALL PRESET Fae CLE pong HP IB STATUS HP 8757C See Plotting this section See Printing this section See Section 8 To Chonnel Service Manual Menu Figure 19 SYSTEM Key and System Menus 1 of 2 32 Operating Reference HP 8757C E SYSTEM SYSTEM MENUS cont d INSTRUMENT STATE ge ep mom Sens CN ae aS HP lB STATUS HP 8757 gt See Plotting this section See Printing this section See Section 8 Service Manual Figure 19 SYSTEM Key and System Menus 2 of 2 The SYSTEM key presents the system menus which allow access to a variety of miscellaneous soft key functions These functions apply to the entire instrument state such as plotting printing AC and DC detection mode number of trace points and service The SERVICE softkey allows access to a series of menus that are described in section 8 of the service manual HP 8757C E Operating Reference 33 34 Plotting HP 8757C HP 757 SYSTEM 1 Figure 20 Plot Menus PLOT presents the first plot menu The plot menus are shown in figure 20 These menus let you custom define and initiate plots on a plotter on the 8757 system interface The analyzer is
391. rough spots immediately discard or mark and send away for repair any connector that has obvious defects like these Mating Plane Surfaces Next concentrate on the mating plane surfaces Flat contact between the connectors at all points on their mating plane surfaces is required for a good connection There fore particular attention should be paid to deep scratches or dents and to dirt and metai or metal by product particles on the connector mating plane surfaces Also look for bent or rounded edges the mating plane surfaces of the center and outer conductors and for any signs of damage due to excessive or uneven wear or misalignment Light burnishing of the mating plane surfaces is normal and is evident as light scratches or shallow circular marks distributed more or less uniformly over the mating plane surface Other small defects and cosmetic imperfections are also normal None of these affect electrical or mechanical performance if a connector shows deep scratches or dents particles clinging to the mating plane surfaces or uneven wear clean it and inspect it again Damage or defects of these kinds dents or scratches deep enough to displace metal on the mating plane surface of the connector may indicate that the connector itself is damaged and should not be used Try to determine the cause of the damage before making further connections Precision 7mm Connectors Precision 7mm connectors among them APC 79 connectors shoul
392. rounding one conductor of a two conductor outlet HP 8757C E Installation 2 3 Table 2 2 Power Cables Available Cable Cable Plug Type HP Part Plug Description Length For Use in Country Number inches 8120 1351 8120 1703 Straight BS1363A 90 Mint Gray Mint Gray United Kingdom Cyprus Nigeria Zimbabwe Singapore 8120 1369 8120 0696 Austrailia Straight ZNSS198 ASC112 90 New Zealand 8120 1689 8120 1692 Mint Gray Mint Gray East and West Europe Saudi Arabia Egypt Republic of So Africa india unpolarized in many nations Straight CEE7 Vil 90 125V 8120 1348 Straight NEMA5 15P Black United States 8120 1398 90 Black Canada Japan 8120 1754 Straight NEMA5 15P Biack 100V or 200V 8120 1378 Straight NEMA5 15P Jade Gray Mexico Philippines 8120 1521 90 Jade Gray Taiwan 8120 1676 Straight NEMA5 15P Jade Gray 8120 2104 Straight SEV1011 1959 i Switzerland 24507 Type 12 8120 0698 Straight NEMA6 15P United States Canada 8120 1957 Straight DHCK 107 Denmark 8120 2956 90 250V 8120 1860 6 Straight CEE22 VI System Cabinet Use Earth Ground L Line Neutrat 2 Part number shown for plug is industry identifier for plug only Number shown for cable is HP Part Number for complete cabie including plug 3 The Check
393. rror trapping Line100 Preset the analyzer and source Line110 Tell the analyzer which device is controlled through the passthru address Address 19 belongs to the source Line 120 Set the source to 250 milliseconds per sweep Perform error trapping Line 130 Turn off channel 2 of the analyzer and select transmission input B for display on channel 1 Line 140 Put the analyzer into non swept mode Clear the status register of the analyzer Set the request mask to 16 bit 4 so that the analyzer will set bit 4 operation complete at the completion of the TAKE SWEEP command Table 1 has a descrip tion of all bits in the status bytes Line 150 Assign the status variable initially to zero Line 160 Command the analyzer to take 10 sweeps Line 170 Wait for the 10 sweeps to completed by testing the status byte to see if bit 4 is set Remain in the loop until bit 4 is set Line 180 Read the analyzer status byte Perform error trapping Line 190 of the loop Line 200 Command the analyzer to output the channel 1 trace data Line210 Define the maximum number of elements to be read into an array Line220 Define the actual number of elements read Line 230 Read the trace data Perform error trapping Line240 Return the analyzer to swept mode The display now updates continuously Line 250 Wait for the ENTER key to be pressed Locate where the prompt will be displayed on the CRT Line 260 Line 270 Line 280 Line 290
394. ruments Covered by Manual 3 Safety Considerations 3 Specifications 4 Analyzer Description 5 Options Available 6 Accessories Supplied 7 Equipment Required But Not Supplied 7 Recommended Test Equipment 8 Table 1 1 Specifications and General Requirements 10 1 2 Supplemental Performance Characteristics INTRODUCTION This operating manual contains installation and operation information for the HP 8757C and HP 8757E Scalar Network Analyzers This manual is part of a 2 manual set that also includes a service manual for performance tests adjustments and service See Replaceable Parts in the service manual for part numbers to order additional manuais The two manuals are available separately or as a set ANALYZER SIMILARITIES The HP 8757E analyzer provides the critical elements of scalar network measurements frequency coverage measurement accuracy and speed The HP 8757C analyzer provides all the capabilities of the HP 8757E plus additional features and enhancements This manual set is written to apply to both the HP 8757C and HP 8757E analyzers Perey Fa E P L oMeeim ese symbois in a table text that is HF HP 8757C E General Information 1 1 MANUAL SET ORGANIZATION The text in this manual is organized as follows a b Title page and warranty statement Table of Contents This is a list of all primary and secondary headings A list of illustrations and tables follows Section 1 G
395. rvice manual is organized as follows a b Title page and warranty statement Table of Contents This is a list of all primary and secondary headings A list of illustrations and tables follows Section 4 Performance Tests This section contains tests to verify that the instrument per formance meets the specifications listed in table 1 1 in General Information Section 5 Adjustments This section provides information required to properly adjust and align the instrument after repair or replacement of an assembly Section 5 Replaceable Parts This section provides lists and illustrations of all replaceable parts and assemblies in the instrument Ordering information is provided Section 7 Manual Backdating This section contains backdating information required to make this manual compatible with earlier shipment configurations of the instrument Section8 Service This section supplies information to troubleshoot and repair the instrument An overall block diagram is provided and each assembly is documented separately with a circuit description schematic diagram component locations diagram and troubleshooting information index This is an alphabetized subject guide to the manual General Information HP 8757C E INSTRUMENTS COVERED BY MANUAL This manual applies directly to any HP 8757C E with a serial number prefix listed on the title page The serial number plate shown in Figure 1 2 is attached to the rear panel o
396. ry title limit line data and source settings of the analyzer This information is packed and encoded for minimal storage requirements thereby mak ing data analysis difficult When stored an ASCII character data string the learn string can later be inputto the analyzer to restore that instrument state by using the INPUT LEARN STRING command The length of the learn string is fixed at 150 bytes Interrogate function The interrogate function is selected with the OP program code and followed immediately by the program code for the func tion to beinterrogated The analyzer will output the present value for the function that was selected to be interrogated The units of the output value will be the same as the units available for setting the value if it can be set The functions valid for interrogation are AF BW DA DB DC DR RL RP SD SL SO SP SR SS and ST Status Selected with the OS program code the analyzer will output 2 sequential 8 bit bytes giving the present instrument status The first status byte is equivalent to the status byte of the serial poll the second status byte is an extended status byte which provides additional information See table 6 for a description of each status byte The status bytes are cleared upon execu tion of either a serial poll device clear DCL selective device clear SDC PRESET or sending the CS or OS commands Error Selected with the 1 or OE2 program codes the analyz
397. s REF LEVEL softkey 18 REF POSN softkey 18 REF STP SIZE softkey 18 register see save recall register rejection out of band UG 13 remote operation mode sweep control QRG 6 IPG 3 IPV 3 IPG 11 IPV 14 removal of handles 2 15 repeat autozero timer 24 REPT AZ ON OFF softkey 24 REPT AZ TIMER softkey 24 resolution tr horizontal display 1 10 14 15 vertical display 14 RESTART AVERAGE softkey 21 return JOSS 13 see also log magnitude revision history HP 8757Q love eui ees es 3 2 HP 8757E 3 3 RGB VIDEO OUTPUT connectors see VIDEO OUTPUT RGB connectors ripple peak to peak UG 13 RPG KNOB S bx 30 Safo cese odes ists 1 3 1 13 SALMON softkey 15 ISAVE 43 save recall register 43 47 DIF 6 UG 9 commands QRG 12 SAVE REGISTR softkey 44 SCALE key 17 SCAG olin chee bared wae Yee EA 17 autoscale 17 commands QRG 8 per division 17 SCALE TO P1P2 softkey 35 SEARCH softkey 20 search cursor 20 secure frequency mode 38 QRG 7 UG 24 SELECT CHAR softkey recall Ri mid cut pU Ra aS 48 SAVE ctu e
398. s Display Units GDU s Moves the pen to the specified eyes XN x y coordinates Both the x and y coordinates must be specified Any number of coordinate pairs can be specified when separated by commas Use of the PD and PU commands determines whether a line is drawn orthe pen is just moved If an x y coordinate is specified outside of the plotting area only that portion of the line within the plotting areais drawn Absolute Character Size w width h height Values allowed are 0 14 0 17Smallestsize Mode labels softkey labels 0 21 0 25 Active Entry Area 0 28 0 34 0 35 0 42 Largest size For monochrome display select pen n 0 to 4 0 Penup Beam off 1 Bright Green 2 Half Bright Green 3 DimGreen 18 Table 4 CRT Graphics Commands 2 of 2 Non HP GL Commands The following HP GL commands will be accepted but their functions are not implemented and no error will be noted IM Input SRQ Mask IP Input P1 and P2 IW Input Window OC Output Current Position OE Output Error PG Output Page SL Character Slant and SR Size Relative for characters hee 88 HP IB Command Command Description Erase Page n where 1 to 8 ifnon value is given all pages are erased Select Graphics GPn m Turn graphics page n 1 to 8 on off m 1 or 0 Pages 1 through 7 may use up to 500 Page On Off 16 bit words Page 8 may contain up to 4000 words GP without parameters selects and turns on page 1 Also reset
399. s a precision 7mm connector is shown being connected to a 7mm test port connector But the steps and principles are the same regardless of connector type Before making any connections inspect all connectors visually clean them if necessary and use a connector gage to verify that all center conductors are within specification If connections are made to any static sensitive device avoid electrostatic discharge by wearing a grounded wrist strap and grounding yourself and all devices before making any connections Align connectors carefully Careful alignment of the connectors is critical in making a good connection both to avoid damaging connectors and devices and to assure accurate measurements AS you bring one connector up to the other and as you make the actual connection be alert for any sign that the two connectors are not aligned perfectly If you suspect that misalignment has occurred stop and begin again Alignment is especially important in the case of sexed connectors such as precision 3 5mm and SMA connectors to avoid bending or breaking the contact pins The center pin on the male connector must slip concentrically into the contact fingers of the female connector and this requires great care in aligning the two connectors before and as they are mated When they have been aligned the center conductors must be pushed straight together not twisted or screwed together and only the connector nut not the device itself shoul
400. s can be used at higher frequencies than 7mm and Type N connectors can Both types are in common use today SMA connectors Figure 8 are low cost connectors generally used up to about 23 GHz A solid plastic dielectric separates the center and outer conductors Precision 3 5mm connectors also known as APC 3 5 connectors are precision air dielectric connectors that will mate with SMA connectors They offer much greater repeatability of connection than SMA connectors do and for this reason they are widely used on electronic test equipment Precision 3 5mm connectors can be used up to about 34 GHz Both SMA and precision 3 5mm connectors are sexed connectors The male contact pin slides into the female contact fingers and electrical contact is made by the inside surfaces of the tip of the female contact fingers on the sides of the male contact pin The mechanical specifications for both SMA and precision 3 5mm connectors give a maximum and a minimum recession of the shoulder of the male contact pin and a maximum and a minimum recession of the tip of the female contact fingers behind the outer conductor mating plane No protrusion of the shoulder of the male contact pin or of the tip of the female contact fingers in front of the outer conductor mating plane is ever allowable and sometimes a minimum recession other than zero is also required Consult the mechanical specifications provided with the connec tor or the device itself Mechanical inspec
401. s engaged by press ing the SAVE key See the SAVE Key description for details and CRT graphics to disk The information will be stored under the active file title which is shown in the title area on the CRT If there is no active file title the information is stored under a default file title FILET If you want to store the information under a different file title enter the desired fite tile using TITLE FILE before pressing STORE TO DISK NOTE instrument state information of an HP 8360 Series Synthesized Sweeper can only be saved or recalled on disk with firmware Revision 3 1 NOTE Alternate state information cannot be saved on disk NOTE User flatness data for an HP 8360 Series Synthesized Sweeper is not stored to disk When pressed STORE TO DISK presents another menu INSTRM STATE stores the analyzer and source front panel settings to disk These are stored under the active file title If there is already instrument state data stored under this file title the new data will write over the old MEAS stores the trace measurement data to disk This information is stored under the active file title MEM stores the trace memory data to disk This information is stored under the active file title mere AT iE paa ata tara i A amr aa iar e IMEAS MEM stores normalized trace data to disk that can later be analyzed with computer This information is stored under the active file title CRT GRAPHIC st
402. s only to the HP 8757C is enclosed with these symbols In a table text that is HP 8757 C only is referenced to a footnote i i H i i i i i i i i fl PO ico Pp ie iW lo iZ i d i i INITIAL INSPECTION inspect the shipping container for damage If the shipping container or cushioning material is damaged keep it until this initial inspection is completed Check the shipment contents for completeness Figure 1 1 shows the HP 8757C Option 001 and its accessories Inspect the analyzer for mechanical damage or defect Follow the instructions in Preparation For Use and then check the analyzer s electrical performance Use the performance tests in section 4 in the service manual If the analyzer does not pass the performance tests if the shipment contents are incomplete or if there is mechanical damage or defect notify the nearest Hewlett Packard office If the shipping container is damaged or the cushioning material shows signs of stress notify the carrier as well as Hewlett Packard Keep the shipping materials for the carrier s inspection Hewlett Packard will arrange for repair or replacement without waiting for a claim settlement HP 8757C Installation 2 1 2 2 PREPARATION FOR USE Power Requirements The analyzer requires a power source of 100 120 220 or 240 V AC 10 48 to 66 Hz singie phase Powe
403. s point to start of page Default Colors DEC Pen Number Color HP 8757C Black Bright White Half bright White Dim White Red Half bright White Dim White Bright White Gold Gold Blue Blue Salmon Salmon Green Green Select BC Black HP BASIC White Default Coiors Red Yellow Green Cyan Blue Magenta Black Olive Green Aqua Royal Blue Maroon Brick Red Orange Brown F Default D Black Monochrome Bright Green Half bright Green Dim Green NO Ut WN m O 19 20 Table5 HP 8757C E Modified ASCII Character Set HP 8757C E MODIFIED ASCH CODE CONVERSION TABLE Note These characters are output only when the LB command is used directly MOST SIGNIFICANT CHARACTER i 2 3 4 null centered space HP logo centered o 8 ETX upper half tic lower half tic left halftic right half tic back space Va shift down line feed degree inv line feed 2 V shiftup LEAST SIGNIFICANT CHARACTER gt co Nox Sct WO N lt x 2 c carnage return horizontal tic OZ lt _ gt 0 1 2 3 4 gt 6 7 8 9 A B c D E F vo vertical tic EXAMPLES HP logo A i V linefeed OA ETX End of text use to end labelling Table 6 HP8757C File Extensions Disk files created by the HP 8757C can be read on any HP 9000 Series 200 300 computer Each file has an extension appended which serves to identify the file type Fi
404. s still within specification after assembly Also verify that the new collet recesses completely and springs back immediately by pressing on it gently with a blunt plastic rod or with the rounded plastic handle of the collet removing tool If it does the connector is ready to use Precision 7mm Connectors 37 GAGING PRECISION 7mm CONNECTORS Extend connector sleeve fully insert gage into connecior 0 0005in Figure 15 Gaging Precision 7mm Connectors 1 of 2 38 Precision 7mm Connectors GAGING PRECISION 7mm CONNECTORS USING GAGE ALIGNING PIN e Use pin wrench to attach aligning pin to gage plunger Al MY XN SY 5 Nw OX S AQ A XX OU Dum K RY me M 0 0005in Figure 15 Gaging Precision 7mm Connectors 2 of 2 Precision 7mm Connectors 39 40 Making Connections Before making connections between precision 7mm connectors review the genera principles out lined in Part One of this manual Connectors must be undamaged clean and within mechanical specification They must be aligned carefully connected by turning the connector nut only and final connections should always be made with a torque wrench Alignment of precision 7mm connectors is made easier by the fact that the connector sleeve on one of the connectors must be extended fully and the sleeve of the other connector retracted fully in order to make the
405. s the insulating dielectric between the center and outer conductors and the center conductor is supported by a plastic support bead inside the connector body Precision 3 5mm connectors are precision devices They are more expensive than SMA connectors and they are durable enough to permit repeated connections and disconnections NMD 3 5 connectors are precision 3 5mm connectors recently developed by Hewlett Packard and used on cables test port connectors and in the HP 85130A special 3 5mm to 7mm adapter set These connectors are especially rugged and are designed to provide an exceptionally strong coupling mech anism for measurement applications SMA and Precision Connectors MALE FEMALE PRECISION 3 5mm CONNECTORS CENTER CONDUCTOR OUTER CONDUCTOR MATING PLANE 9 OUTER CONDUCTOR OUTER CONDUCTOR CENTER CONDUCTOR OUTER CONDUCTOR MATING PLANE a e T TT ai e TT a TAa Figure 22 Precision 3 5mm Connectors SMA and Precision Connectors 57 58 MATING SMA AND PRECISION 3 5mm CONNECTORS All SMA connectors should be inspected mechanically using a precision connector gage before use and before being mated to any precision 3 5mm connector Out of specification SMA con nectors can damage other connectors permanently even on the very first connection if an SMA connector is to be mated to a precision 3 5mm connec tor the SMA connector must meet the setback specifications
406. s the connector and the least pressure possible to avoid damaging the center conductor This is especially necessary when when female connectors are being cleaned to avoid snagging the cleaning swab on the center conductor contact fingers An illuminated magnifying glass is very helpful in making these small areas easy to see Cleaning Connectors on Static Sensitive Devices Cleaning connectors attached to static sensitive circuits test set connectors for example requires special care to avoid static discharge When cleaning such connectors Figure 4 always wear a grounded wrist strap and before touching the connector itself even with a plastic swab discharge static electricity to ground This is easily done by grasping the outer shell of the test port briefly These precautions will prevent electrostatic dis charge ESD and possible circuit damage Cleaning CLEAN CONNECTORS CAREFULLY Try clean compressed air Freon first If solvent is necessary use pure liquid Freon Use as little solvent as possible and avoid wetting plastic connector parts Clean connector threads first Clean hard to reach areas by wrapping lint free cloth around a thin wooden or plastic rod After cleaning them blow connectors dry with clean compressed air Freon CLEANING CONNECTORS ON STATIC SENSITIVE DEVICES COMPRESSED LIQUID COTTON GROUNDED AIR FREON SWAB WRIST STRAP Figure 4 Cleaning Microwave Connectors C
407. sably distort the passband response Notice the S in the mode label area indicating that smoothing is active for channel 1 Smoothing keystrokes SPCL Accesses the special functions menu SMOOTH ON OFF Turms smoothing on SMOOTH APERT Allows the smoothing aperture to be changed the default value is 5 SMOOTH ON Turns smoothing off Th cee 2 earn m STOP oai Basar STAT 7 Adaptive normalization HP 8757C only This feature allows the user to reduce the frequency span of measurement without having to recalibrate Note that the resolution the nurnber of points of the narrower frequency span is not changed as the trace is expanded This function utilizes the calibration data stored in memory and interpo lates between the original calibration points Adaptive normalization is only available for normalized traces MEAS MEM or if MEM is selected in the display menu An asterisk is displayed in the mode label area when adaptive normalization is active If the frequency span is increased beyond the original calibration span the measurement becomes uncalibrated and the is replaced with a U in the mode label area The following sequence demonstrates how to use the adap tive normalization function of the HP 8757C and the marker functions of the HP 8350B and HP 8340B 8341B sources to expand and display a selected p
408. scriptions QRG 21 indiCatolS vosxeatecen tare ks 52 lg v nce v CEA SL P PRA ce 6 symbols 5 UG 5 STEP KOyS catu raya 30 step commands QRG 9 STEP SW ON OFF softkey 41 STOP LABEL softkey 39 STOP SWEEP connector 1 11 61 STORE OPEN softkey 23 STORE SHORT softkey 23 STORE THRU softkey 23 STORE TO DISK softkey 44 STP ONE LEFT softkey recall ccv b EE ECCE en 49 SAVE uu ans LE a PC ACERS ES 45 system nnn 39 STP ONE RIGHT softkey recall Binds et 49 SAVE PP 45 Systel oho v Iu De wears eels 39 SWEEP iN 0 10 V connector 1 10 61 sweep manual veces 41 mode uui te e on 41 mode commands QRG 11 QRG 15 seht ce i ua 41 remote IPG 11 IPV 14 SWEEP MODE softkey 41 SWEEPER softkey 42 sweep requirements Fit ocak te 1 9 voltage erudi daa tona dee OSes 1 9 SWR ive hua ee ad aa 13 UG 18 syntax input MU Sect QRG 2 3 SYS INTF ON OFF softkey 41 SYSTEM key 32 system calibration commands QRG 11 interface eee ee QRG 4 T tabular data Hint ss Soe eee ena eae 37 marker print 37 TEMPCOMP ON OFF 25 temperature compensation 25 a 25 operating
409. sets the passband of the filter to the reference line facilitating average insertion loss measurements and magnifying the passband region for flat ness measurements without resetting the reference levels The following sequence sets up the reference functions REF Activates reference level function and displays menu REF POSITON Allows the user to change the position of the reference line or Steps the reference line up or down to any of the major graticules REF LEVEL Allows the user to change the position of the trace relative to the position of the reference line 0 dBm dB Sets the reference level to 0 dB The following figure shows the complete transmission response of the bandpass filter under test The display exhibits several important filter parameters The cursor functions provide a powerful tool for measuring specific points or the difference between two points Note that the cursor value is displayed in the mode label area above the reference level value the negative value indicates loss a positive value would indicate gain Insertion loss Insertion loss can easily be determined to 0 01 dB resolution by utilizing the cursor to measure the magnitude at any fre quency of interest When the cursor is active the magnitude and frequency of that point will be presented in the active entry area of the display Average insertion loss is determined by utilizing the scale and reference l
410. sion is BEGIN this signifies the beginning of the data array to be input Dynamically allocate space for the data array to be input Input the data from the file specified Begin a loop which converts the data string to numeric data pairs Convert a REAL data point from the string into a numeric value and store the numeric value in an array Convert an IMAGINARY data point from the string into a numeric value The data is listed in pairs separated by a comma with the REAL component preceeding the IMAGINARY component Proceed to the next data pair After completing input of the data array set Done greater than 0 Finish of the construct which allowed for the conditional execution of one of two cases Complete IF THEN sequence Check to see that Done is greater than 0 Line 400 This statement is used to return from the subprogram at some point other than the SUBEND statement It allows for more than one exit from a subprogram Line 410 Define a subprogram called by Read citifile to locate the next token The tokens of interest to this program are VAR and BEGIN Line 420 Locate the position of the next ASCII space within the data string Line 430 Ifthe value returned for the position of the next ASCII space is 0 then the ASCII space character doesn t exist in the string being searched Line440 Set the token to whatever is currently in the data string Line 450 Set the string to a null
411. sity interpolate To determine a value of a signal between two adjacent points by a procedure or algorithm 1 0 path input output path Local Lock Out A condition or command that prevents analyzer front panel entries and disables the LOCAL key Local operation To operate manually from the front panel Log An abbreviation for logarithm Logger A circuit designed to output a voltage proportional to the log of an input voltage Magnitude The magnitude of variation in a changing signal from its zero value The iength of a vector Marker An indicator at a specified frequency point Menu A selection of softkey choices Microprocessor kernel The devices which are critical to the basic operation of the micro processor Monitor Any external display Monochrome Having only one chromaticity or color Muitisync Atype of monitor that can synchronize its horizontal sweep to various frequencies within a specified range Nit The unit of luminance photometric brightness equal to one candela per square meter Normalize To subtractone trace from another to eliminate calibration data errors or to obtain relative information PAL An abbreviation for Programmable Array Logic A programmable multiple input output device which outputs a specific pattern for a given input Passthrough mode That mode of the analyzer which allows HP IB commands from a controller to be sent to devices on the analyzer s system interface bus
412. smission using any of the four three on the HP 8757E display channels with either a single detector at input A B C HP 8757C Option 001 or R or two detectors in a ratio measurement i e A R B R etc In the simplest transmission setup the device attaches directly to the source and the detector to the output of the device This configuration will produce accu rate results when a leveled source is utilized with a low reflection test device However when source mismatches occur they can create power level variations which will pro duce system errors Ratioing provides an improvement in effective source match by eliminating the effects of source power variations com mon to both reference R and test inputs This technique is particularly appropriate for measurement of devices with a low insertion loss poor input match or an unleveled source Since active devices devices with gain usually require measurements with varying inputs ratioing eliminates the need to recalibrate each time the power level is changed also it reduces the ripple associated with source mismatches to which many active devices are particularly sensitive HP 8757C E HP 83508 Scalar Network Analyzer Sweep Oscillator RA PE T Device Under Test Detector gt Detector Measurement setup for insertion loss and gain Insertion loss and gain are ratios of the output to input sig nals When set up as shown below the results can be read dir
413. source to those given by the user Line 190 Exit passthru mode by addressing the analyzer Line 200 End program execution Running program 3 1 Clear the program memory of the computer and type in the program 2 Press RUN on the computer 3 Thecomputer presets the analyzer and the source reads the start and stop frequency of the source and displays it _ on the CRT of the computer At preset the source defaults to the full frequency range of the plug in The values read then represent the frequency limits of this plug in When the computer stops it displays the prompt Start frequency GHz Enter a start frequency in the frequency range of the plug in and press Continue 4 The computer displays the prompt Stop frequency GHz Enter a stop frequency in the frequency range of the plug in but higher than the start frequency and press Continue 5 The computer sets the start and stop frequency of the source to those you entered The analyzer immediately begins sweeping the frequency range you defined 6 Try deleting or commenting out line 190 in the program Now when the program ends the analyzer shows the message DATA PASSTHROUGH EXECUTING and the display is frozen not sweeping To exit passthru mode type OUTPUT 716 and press EXECUTE on the computer The analyzer displays DATA PASSTHROUGH COMPLETE and begins sweeping Points to remember You must address the analyzer after using passthru mod
414. source to local mode Line 100 Temporarily stop execution Line 110 Preset the analyzer and source Line 120 program execution Running program 1 Press SHIFT RESET on the computer Type SCRATCH and press EXECUTE This clears the program memory of the computer 2 Typein the program 3 Press RUN on the computer 4 When the program stops the analyzer is in remote mode You can verify this by observing the lights in the INSTRUMENT STATE area of the analyzer The R remote and L listen lights should be on Try pressing any key on the analyzer except Nothing happens The source is also in remote mode Now press LOCAL and verify that the keys on the analyzer are active Also notice the R light went out when you pressed LOCAL The source went into local mode along with the analyzer 5 Press Continue on the computer The analyzer is again in remote mode This time however the LOCAL key is locked out Try pressing LOCAL and the other keys None of the keys on the analyzer or the source cause any action 6 Press Continue on the computer All instruments on the HP IB interface are returned to local mode includ ing the analyzer and source To set only the analyzer into local mode the LOCAL 716 command can be given from the computer Verify that the R light on the ana lyzer is off and the REM light on the source is off 7 Press Continue on the computer The analyz
415. specifications 1 3 1 8 PLOT softkey 34 e o janine 34 UG 10 Sane ee dea ee 35 commands QRG 10 CUSTOM s obe ePi US eget e 35 PLOT ALL softkey 34 PLOT CUSTOM softkey 34 PLOT GRID softkey 35 PLOT LABELS softkey 35 PLOTTER softkey 42 PLOT TRACES softkey 35 piotters compatible 34 PLT BUF ON OFF softkey 41 POINT LIMIT softkey 28 points number of trace 1 10 13 38 command vss 1 see number of trace points IPG 11 POS Z BLANK connector 1 9 61 power EL ALAS CAG Kees 2 3 detector calibration 25 line module 2 2 problems os vase Cer yeu DIF 2 requirements 1 12 2 2 preset conditions 50 QRG 3 IPG 3 iPV 3 KEY where X represents the page number 1 General information 2 Installation X Operating Reference UG X User s Guide RO X Remote Operation looseleaf page behind tab QRG X QuickReference Guide IPG X Introductory Programming Guide for HP9000 Series 200 300 Computer IPV X introductory Programming Guide for HP Vectra DIF X In Case of Difficuity HP 8757C E Index iii PRESET key 50 PREV PAGE softkey 45 48 PRINT softkey
416. splays the return loss of the bandpass filter Since the return loss is high in the passband of the fil ter only a small portion of the incident signal is being reflected off the filter This indicates a good match between the filter and the test system impedance The return loss in the filter s reject band is approximately 0 dB which corre sponds to an almost full reflection of the incident signal A good passband filter should transmit the signal in the pass band i e small reflection high return loss while rejecting all signals outside of the passband i e high reflection low return loss CHi A R M dB AEF ot H 1 i TEN i i i QUERN SYRT TS SacoUuHz GALA iG 2485GHz STOF 11 24082 SWR To display reflection data in terms of SWR select DISPLAY then the TRC FMT SWR dB softkey SWR is a unitless value a SWR 1 corresponds to no reflection perfect match while an infinite SWR corresponds to 100 reflect ion poor match SWR is only available for channels 1 and 2 and for ratioed or normalized measurements with 401 points or fewer 18 Simultaneous transmission and reflection measurements Simultaneous insertion loss and return loss measurements are useful when adjusting the impedance match of a device for maximum power transfer With the HP 8757C E these measurements are easily accomplished The
417. st strap and grasp the outer grounded shell of the test port briefly before removing or inserting the collet Ground all tools in the same way Precision 7mm Connectors COLLET REMOVAL COLLET REMOVING TOOL HP Part Number 5060 0236 Pull back the handle of the collet removing tool Keep the handle pulled back and insert the tool into the connector until it comes to rest lightly on the interior support bead Release the handle and remove the oid collet and the tool COLLET INSERTION PUSH LIGHTLY TO COLLET TWEEZERS SNAP INTO PLACE 4 SLOT COLLET 6 SLOT PRECISION COLLET HP Part Number 1250 0907 HP Part Number 85050 20001 Figure 14 Center Conductor Collet Removal and Insertion Precision 7mm Connectors 35 36 Selecting a Connector Gage Care is necessary in selecting a connector gage to measure precision 7mm connectors Some gages have a very strong gage plunger spring strong enough in some cases to push the center conductor back through the connector damaging the device itself Other gages may compress the center con ductor collet during the measurement giving an inaccurately low reading of the actual collet protru sion Connector gage kits containing a gage recommended for precision 7mm connectors and ail of the other items required are included in many Hewlett Packard calibration kits and they are also available separately Part numbers are given in Part One of this Microwave Connector Care Manual Pre
418. stem functions that apply to the entire instrument they are not channel specific SYSTEM SAVE RECALL PRESET and LOCAL implement such functions as HP IB plotter printer and disk controls built in diagnostic tests front panel save recall instrument preset and HP IB instrument addresses STRUNEN STATS General measurement sequence Even with its wide range of capabilities the HP 8757C E is easy to operate Common measurements can be set up with only a few front panel selections This section describes a general approach to performing network measurements with the HP 8757C E The following sequence is used throughout this User s Guide to illustrate the use of the HP 8757C in its various operat ing modes The individual steps are discussed in detail in the sections that follow Preset Return to a known state Connections Set up the test configuration for your particular device under test Controls Set up the instrument with the following steps 1 Select measurement input 2 Set up source parameters Calibrate Characterize the systematic errors and remove their effect from the displayed data Save Save the instrument configuration and calibration to facili tate recalling measurement states Measurement Measure the performance of the device under test Utilize the cursor functions to extract key measurement information Output Results Create a permanent record of your measurement
419. stored in registers 1 and 2 and the analyzer will display the measurement results for both conditions NOTE For more information on the alternate sweep function refer to the HP 8757 User s Guide i The number of channels that can be shown on the CRT is limited by the number of trace poinis selected All four channels can be shown when 101 201 or 401 points are selected With 801 trace points only channels 1 and 2 are available With 18 01 trace points only channel 1 is available The channel trace memory for channels that are turned off will be destroyed when you choose 801 Or i180H points Autozero of DC Detectors When the analyzer is in DC detection mode it must periodically zero its AC DC detectors to maintain accurate low level measurements When using a source connected to the 8757 system interface you can engage the autozero function and let the analyzer control the source power off on sequence In order to preserve the front panel settings of the source the analyzer must use save recall register 9 on both the source and the analyzer Register 9 is accessed each time an autozero is performed whether itis forced by the operator or the autozero repeat function is engaged Do not use register 9 for storing other information The information will be lost when the analyzer writes over it Save Recall Registers The save recall registers store most of the front panel settings with few exceptions Some of the sys
420. surement number the reading and the frequency on the computer CRT Command the source to increment the CW frequency by the step size set earlier line 90 This is a very fast way of setting a series of equally spaced frequencies Increment the variable that contains the current frequency This variable is only used for printing the current frequency at each repetition of the loop End of the loop Command the source to sweep from 2 to 4 GHz The source exits CW mode and returns to start stop mode Line210 Command the analyzer to return to swept mode The analyzer again updates the trace information on the CRT This command also exits passthru mode Line220 End program execution Running program 5 1 Clearthe program memory of the computer and type in the program 2 Press RUN on the computer 3 The source frequency is set immediately to 2 GHz and the computer begins reading reflection input A on the analyzer and printing the measurements After 21 readings the program ends Program 6 trace transfer One feature that sets the HP 8757C E apart is its ability to transfer an entire measurement trace to a computer at very high speed A complete high resolution 0 01 dB 401 point measurement can be sent to the computer in 35 milliseconds binary format or 800 milliseconds ASCII format Transfer time will be less for fewer points per trace and greater for more points per trace The analyzer gives you compl
421. sweep mode on off Display the measurement menu Display the display menu Print all to monochrome printer except softkeys and CRT graphics Print tabular display data in monochrome Print tabular marker cursor data to external printer Print all to color printer except softkeys and CRT graphics Passthrough address set to d R A ratio measurement R B ratio measurement R C ratio measurement Recall register n Reference level set to d Service request mask set to d Reference position set to vertical division q Restart averaging Di h le menu isplay oe Set cursor to horizontal position d Display the reference menu M Scale per division set to d Display the cursor menu Display the average menu Display the calibration menu Display the special menu Display the system menu Display memory data Manual calibration of DC detectors Non standard sweep mode on off Output cursor value Output trace data Output error status of display channel 1 Output error status of display channel 2 Output identity Output keycode of last key pressed Output learn string Output memory data Output normalized measurement memory data Output interrogated parameter value xx BW DA DB DC DR RL RP SD SL SO SP 5 55 5 Store all instrument information to disk in file Store CRT graphics to disk in file
422. system interface is on When itis off SYS INTF OFF is shown the status line on the CRT Check that the HP IB address of each instrument is set correctly and that no two instruments are setto the same address To check the expected address for each instrument in the system press LOCAL Then press the softkey for each instrument and the HP IB addresses will be shown on the CRT Check the address for each instrument and verify that they correspond to the expected addresses Ifthe addresses do not agree change them using the local menu or resetthe HP IB address on the instrument itself HP 8757C E In Case of Difficulty 3 Other Cable Connections For most uses the STOP SWEEP POS Z BLANK and SWEEP IN 0 10V analyzer outputs must be connected to the source Section 2 Installation describes how to make these connections with the HP 8350B Sweep Oscillator and the HP 8340 and 8341 series Synthesized Sweepers Other connec tions may be necessary for different applications Remote Operation Most remote operation problems occur due to improper programming Check all program code for proper syntax Ensure that the proper number of bytes are transferred when sending or requesting data to and from the analyzer When transferring binary data ensure that an HP 98764 Printer is not connected to the bus This may prevent proper transfer e Ifa printer is connected to the 8757 system interface do not set it to send out an SRQ if th
423. t 4 is set If it is then 10 sweeps have been completed If bit 4 is not set then continue to read and test the status byte until it is set Command the analyzer to output the channel 1 trace data Read the trace data Return the analyzer to swept mode The display now updates continuously Temporarily stop program execution Put the analyzer into non swept mode Clear the status register of the analyzer Set the request mask to 16 bit 4 OPERATION COMPLETE so that the analyzer will send the computer a service request SRQ at the completion of the TAKE SWEEP command This is the same as in line 100 except we will look for interrupts this time Define the routine to be executed when the SRQ is received from the analyzer The label Srq recv is equivalent to line 230 Turn on interrupts in the computer Specifically allow an HP IB service request to interrupt the computer See the BASIC Language Reference of the computer for more detail about HP IB programming Line210 Command the analyzer to take 10 sweeps Line 220 Wait for the SRQ from the analyzer by putting the computer into a tight loop Ifa PAUSE statement were used the computer would not respond to interrupts Line 230 The computer begins execution here after receiving the SRQ from the analyzer Line 240 Read the status byte of the analyzer This action clears the SRQ flag of the analyzer Line 250 Disable interrupt generation from the analyzer Line
424. t bit of the current ana lyzer address For example since the analyzer default address is 16 decimal 10000 binary the default 8757 SYSTEM INTERFACE address is 17 decimal 10001 binary As another example if the analyzer address is set to 7 decimal 111 bin ary then the 8757 SYSTEM INTERFACE address becomes 6 decimal 110 binary This example shows how to pass through commands to the source with address 19 decimal using the analyzer default address 16 decimal 1 Address device 16 the HP IB port on the analyzer and send the command PT19 2 Address device 17 the 8757 SYSTEM INTERFACE and send commands to the source 3 Address device 16 This returns the analyzer to its normal HP IB operation This example shows how to pass through commands to the plotter with address 05 decimal using the analyzer default address 16 decimal 1 Address device 16 the HP IB port on the analyzer and send the command PTO5 2 Address device 17 the 8757 SYSTEM INTERFACE and send commands to the plotter 3 Address device 16 This returns the analyzer to its normal HP IB operation CRT graphics The CRT screen of the analyzer may be used as if it were an external HP IB graphics plotter By defining the analyzer CRT as the plot device used by the computer the operator may pass through graphics commands which will plot graphics on the CRT The graphics commands are mostly a subset of the Hewlett Packard Gra
425. t mode Sweep off hold data on the CRT Mode Swi Swept mode Sweep on continuously track sweep ramp voltage and update trace data on the CRT SW2 1 TSd 3 sweeps be taken for accurate data Learn ILs 4 Input learn string sis string of 150 binary bytes that were output by the String output learn string command ASCIIHabel ASCH label term where ASCII label is lt 7 characters and term is a valid terminator WM NC Write Title to the CRT sisan ASCII string of up to 50 characters 2 Revision 3 1orabove for an HP 8757C revision 4 1 or above for an HP 8757C 3 Available only if display trace data is in log magnitude format see 050 Write softkey label fora particular softkey sis an ASCII string the first character is the softkey number range 1 to 8 followed by the label The label can be sent in the following forms one word label TASCH label term two word label Write to the channel memory Data is transferred from the computer to the channel memory of the analyzer Several parameters must be properly set before the transfer is made data format must be set using the FDx command the desired channel memory is selected by making that channel the active channel the number of points transferred must equal the present number of points trace 15 Table 3 Output Modes 1 of 2 HP IB ore pvr come ren e 16 Output Interrogated Paramet
426. tamination can also result from setting the connectors contact end down on a work surface even on one that appears to be clean and from touching the mating plane surfaces even with clean hands Particles left behind after cleaning for example fibers from cleaning swabs can generally be removed by blowing the connector dry with clean compressed air Visual Inspection 8 CLEANING Try compressed air first if a solvent is necessary use pure liquid Freon Clean very dirty connectors with pure isopropanol Other solvents should not be used Use the least amount of solvent possible and avoid wetting any plastic parts in the connectors with the solvent Never spray solvent directly into a connector Check solvents periodically for contamination Careful cleaning of all connectors is essential to assure long reliable connector life to prevent acci dental damage to connectors and to obtain maximum measurement accuracy and repeatability Yet it is the one step most often neglected or done improperly Supplies recommended for cleaning microwave connectors are shown in Figure 3 Cotton swabs are the most useful generally for cleaning connector threads and mating plane surfaces A lint free cleaning cloth is useful for cleaning precision 7mm connectors and the interior surfaces of all connec tors Compressed Air Always use protective eyewear when using compressed air even if the source is a small pressurized can L
427. te GRAPH COLOR which is available on the HP 8757C may only be utilized with a HP Paintjet color printer Both of these functions will output everything displayed except for any messages in the display s active entry area and the softkey menu Selecting LABELS in the SYSTEM menu offers the user the choice of turning on or off the labels or title of the current display prior to printing PRINT DATA will output each point on the trace in tabular form PRINT MARKERS will list just the information relating to markers and cursors cur rently displayed P T E R 2 Transmission measurements with the HP 8757C E This chapter demonstrates many of the features of the HP 8757C E A complete measurement setup is given for each example following the same basic measurement sequence of chapter one The examples provided in this doc ument represent typical scalar network measurements This section describes transmission measurements of insertion loss 3 dB bandwidth peak to peak ripple and gain com pression Some of the features presented are averaging smoothing adaptive normalization and power sweep Modify the instrument setups shown to suit your particular needs For further information on any of the measurements shown refer to the HP 8757C E Operating Manual for the most complete description of the analyzer s operating modes parameters etc Basic system configuration The HP 8757 analyzers can measure tran
428. tem menu functions are not stored because they apply to every instrument state rather than to a specific channel The following information is stored in the save recall registers The channel status which channel is active and which channels are on For all channels Measurement selected A A R etc Display mode MEAS MEM etc Averaging on off status Averaging factor Reference level Reference position Scale per division Smoothing on off status Smoothing factor Detection mode AC or DC Number of trace points Internal modulation on off status Cursor on off status Cursor position Cursor delta on off status Cursor delta position Cursor search value e 6 e 6 6 e 6 In Case of Difficulty HP 8757C E Adaptive normalization on off status Non standard sweep on off status Limit line on off status channels 1 and 2 1 Registers 1 through 4 also save the following Trace memory at 401 points for channels 1 and 2 e Limitline entries for channels 1 and 2 e Title Thefollowing information applies to the entire instrument rather than the individual channels and is not saved System Interface on off status Labels on off status Title on off status Frequency labels on off status Repeat autozero on off status Color selection CRT intensity HP IB addresses Disk unit number Disk volume number ee0neeeese NOTE Instrument state information of an HP 8360 Seri
429. ter a new address Allowable values are 0 through 29 Enter the new value with the numeric keypad and terminate the entry with the ENT key Do not settwo instruments to the same HP IB address The CRT shows the new HP IB address This address is stored in memory and is not changed by turning the LINE switch off or when the analyzer is preset Be sure that the address set for each instrument matches the address physically set on the instrument Operating Reference HP 8757C E SAVE SAVE MENUS The SAVE key allows you to save the current instrument state in save recall registers in the analyzer The information is stored in non volatile memory and will be available even if power is interrupted until INSTRUMENT STATE RECALL PRESET R Tr Tt e e e HP iB STATUS 8757C Figure 24 SAVE Key and Save Menus the registers are written over or cleared with the CLEAR SAV RCL softkey To save the current instrument state in a register press SAVE SAVE REG appears in the active entry area Enter the register number using the numeric keypad where you wish to store the current instrument state No terminating key is needed 9 different settings can be stored in registers 1 through 9 of the analyzer After you enter the register number 1 through 9 the analyzer saves the current instrument state in the appropriate register This takes only a moment then COMPLETE appears in the active entry a
430. th 3 5 inch and 5 25 inch formats Follow instructions provided with the HP 11613 Only software revision 3 0 should be used with the HP 8757C E No other calibration is required The entire process except for the analyzer warm up takes less than 15 minutes 12 In Case of Difficulty HP 8757C E MICROWAVE CONNECTOR CARE Copyright HEWLETT PACKARD COMPANY 1986 1400 FOUNTAINGROVE PARKWAY SANTA ROSA CA 95401 U S A MANUAL PART NO 08510 90064 Microfiche Part Number 08510 90066 Printed APRIL 1986 LA 5i cac CONTENTS General Introduction 1 PART ONE PRINCIPLES OF CONNECTOR CARE INTRODUCTION 3 HANDLING AND STORAGE 4 ELECTROSTATIC DISCHARGE 5 VISUAL INSPECTION 6 Obvious Defects or Damage 6 Mating Plane Surfaces 6 Precision 7mm Connectors 6 Sexed Connectors 6 SCIaIGIIBS S eX DOCE eras Kk DEN S ety da tos do Sure Mod Ss eus 7 Metal and Metal By Product Particles 7 CLEANING da ea tactu qs Veag amd 8 Compressed 8 Cleaning Solvents 9 Recommended Solvents 9 Using Solvents 10 Cleaning Technique 10 Cleaning Connector Threads 10 Cleaning the Connector Mating Plane SUMACOS S Cu ee Law ERR RU tex 10 Cleaning Connectors on Static Sensitive DOVICBS RARE
431. the calibration block When the connector is measured this outer bushing will rest on the outer conductor mating plane inside the connector Follow the instructions for zeroing the gage given in Part One of this Microwave Connector Care Manual To gage male SMA and precision 3 5mm connectors center the gage carefully relative to the connec tor before inserting it As you insert the gage be sure that the male contact pin slips into the hole for this purpose in the gage plunger as it will if the gage is exactly centered in the connector This is required to give the correct center conductor measurement for male connectors the position of the shoulder of the male contact pin not the tip relative to the outer conductor mating plane Gently rock the connector gage within the connector to make sure that the gage and the outer conductor have come together flatly Then read the recession or protrusion from the gage dial Female SMA and Precision 3 5mm Connectors Gages used to measure female SMA and precision 3 5mm connectors are usually marked F and are zeroed using the flat end of the calibration block supplied with the gage Figure 28 This end of the gage block is usually marked F When the connector is measured the gage plunger comes to reston the outer end of the female contact fingers Gaging female SMA and precision 3 5mm connectors is done in the same way as it is for male connectors SMA and Precision 3 5mm Connectors 67 68 MAL
432. the end of line string carriage return linefeed that is sent after any IOOUTPUT command Command the analyzer to input data into the trace memory of channel 2 Write the binary data array to the trace memory of channel 2 Perform error trapping Enable the end of line string carriage return linefeed that is sent after any IOOUTPUT command Autoscale the display on channel 1 End program execution Define a subroutine that outputs commands to the analyzer Perform error trapping Return from the subroutine Running program 6 1 Clearthe computer CRT and type in the program 2 Press ALT R S on the computer 3 Watching the analyzer CRT you will see DATA DUMP TO HP IB when it begins sending trace data to the computer and DATA DUMP TO TRACE MEMORY when the computer sends data back 4 Watching the analyzer CRT press ENTER on the computer The computer again reads and writes a trace of data The analyzer displays the same messages This time the transfer occurs much more rapidly A binary transfer takes about 35 milliseconds to be completed while an ASCII trace transfer requires about 800 milliseconds each way 5 Press ENTER on the computer The computer calculates an arbitrary function and sends it to trace memory of the analyzer where it is autoscaled and displayed This function has no significance It repre sents a special calibration trace such as a short open average With a computer the an
433. the expression Done to zero This will be used to determine if all data has been read into the data array Line 180 Define a loop which is repeated until the value for Done is greater than zero Line 190 Line 200 Line 210 Line 220 Line 230 Line 240 Line 250 Line 260 Line 270 Line 280 Line 290 Line 300 Line 310 Line 320 Line 330 Line 340 Line 350 Line 360 Line 370 Line 380 Line 390 Statement used to input data from the file of interest and assign the values entered to a string variable This function is used to return the string stripped of ali leading and trailing ASCII spaces Call a subprogram used to locate the first word on the line If the boolean expression within the parenthesis is evaluated as true then the following conditions are tested In this case the expression can be set true by the Get next token subprogram Provide for conditional execution of one of two program statements using the string expression If the string expression is VAR then remove two words from the data array This is done to locate a piece of data that specifies the length of the array to follow Begin loop to remove two words Call to subprogram which removes a word Continue the loop until two words have been removed Convert the string expression for the length of the data array into a numeric value that can be used in the program as a counter If the string expres
434. the male bushing is flat and has a hole in it and the gage plunger is inserted through the bushing so that the plunger protrudes from the bushing when the bushing has been attached Zero the gage using the recessed end of the gage calibration block Insert the gage plunger into the hole in the gage calibration block and zero the gage according to the instructions given in Part One of this Microwave Connector Care Manual Then measure the connector insert the gage carefully into the male connector so that it is centered and the flat outer part of the gage bushing rests on the outer conductor The male contact pin slips into the hole for this purpose in the gage plunger Gently rock the connector gage within the connector to make sure that the gage and the outer conductor have come together flatly When the gage pointer settles consistently at a reading read the gage indicator dial Counterclockwise deflection of the gage pointer a minus reading on the gage indicator dial indi cates that the shoulder of the male contact pin meets its minimum specification of being recessed at least 0 207 inches The amount of deflection tells how much more than the minimum the shoulder of the contact pin is recessed A reading of minus 0 003 inches for example indicates a recession of 0 210 inches the maximum recession allowed in HP Precision Type N connectors In the same way clockwise deflection of the gage pointer a plus reading on the gage ind
435. the maximum input power of the detector 20 dBm use attenuators where appropriate Once the measurement has been completed a new frequency may be chosen A convenient way to accomplish this is to set a step size in GHz and increment the frequency by selecting SHIFT CW It is not normally necessary to adjust the power sweep parameters once they are set up However the sweeper must remain in CW mode The following figure displays gain and the absolute input and output power at 1 dB compression for a HP 8447D Amplifier Channel 1 was calibrated across the 100 MHz to 1 5 GHz frequency range The plug in power level was set to 4 dBm with a 10 dB and 6 dB pad attached to the output The other measurement parameters may be determined from the figure an ean a SSCS dB 3 8 iR 867 29 55 Ho Gey ame a R 48 2 9 0m EP i H i i i i 223 7d ERE ME STAT 1 15682Hz CASS 1 48BH50H2 SYGP s 488SSHr For more information on scalar analysis of amplifiers and mix ers refer to Application Notes 345 1 and 345 2 respectively C H A P T E R 3 Reflection measurements with the HP 8757C E The transmission measurements discussed in chapter 2 are only part of the network measurements picture Measuring the return loss or SWR completes the device characteriza tion This chapter demonstrates how to perf
436. the source or the computer See Replaceable Parts for ordering information HP 8757C E literature 8757C E Operating Manual Programming Note Quick Reference Guide for the HP 8757C E Scalar Network Analyzer Source literature e Programming Note Introductory Operating Guide for the HP 8350B Sweep Oscillator with the HP 9000 Series 200 Computers BASIC Programming Note Quick Reference Guide for the HP 8350B Sweep Oscillator e Programming Note Introductory Operating Guide for the HP 8340A Synthesized Sweeper with the HP 9000 Series 200 Computers BASIC Programming Note Quick Reference Guide for the HP 8340B Synthesized Sweeper HP 9000 series 200 300 computer literature BASIC Operating Manual BASIC Programming Techniques BASIC Language Reference BASIC Interfacing Techniques BASIC Graphics Techniques General HP IB literature e Condensed Description of the Hewlett Packard Interface Bus Tutorial Description of the Hewlett Packard Interface Bus SAME CONNECTIONS AS HPB8350B HP IB UE om goog D mua cao gupa jii ened onun ooon Q sao onw 834598 834123 AM INPUT L TYPE NIUM TO M TO 8757C E RORPTER BARREL MOD DRIVE HP 8009 SERIES 200 GR 380 COMPUTER our 83500 PLUG IN HP 85027R DIRECTIONAL BRIDGE Equipment required 1 HP 8757C E Scalar Network Analyzer 1 HP 83508 Swe
437. the two connectors straight together with the male contact pin precisely concentric with the female Do not rotate either connector or overtighten the connection Turn only the outer nut of the male connector and use a torque wrench 5 Ib in 56 N cm for the final connection Note that this torque is less than is used when mating precision 3 5mm connectors with each other A torque wrench suitable for SMA connectors preset to 5 Ib in 56 N cm is available as HP Part Number 8710 1582 These precautions are all necessary because of the nature of SMA connectors SMA connectors are designed to be inexpensive one time only connectors They are not precision mechanical devices and they should be used carefully with a full knowledge of their limitations Worn damaged or out of specification SMA connectors can destroy a precision 3 5mm connector even on the very first connection When more than a few connections of SMA connectors to a precision 3 5mm interface will be made a 8 5mm to 3 5mm adapter sometimes called a connector saver is generally installed on the 3 5mm connector in this way the original connector is protected from damage and only the adapter needs to be replaced when it is worn Adapters are discussed later in this section SMA and Precision 3 5mm Connectors i d UR Yin Sie APC 3 5 APC 3 5 p NONI PRECISION 3 5mm SMA INTERFACE O Z Y ZN THIS WALL DIMENSION
438. tion 17 18 SMA CONNECTORS MALE FEMALE BSS SS OUTER CONDUCTOR MATING PLANE Figure 8 SMA Connectors PRECISION 3 5mm CONNECTORS MALE FEMALE OUTER CONDUCTOR MATING PLANE Figure 9 Precision 3 5mm Connectors Mechanical Inspection Types of Gages A different connector gage is required for each type of connector Sexed connectors require two gages male and female or in the case of Type N connectors a single gage and male and female adapter bushings and every connector gage requires a gage calibration block for zeroing the gage Connector gages for precision 7mm connectors also require an aligning pin and pin wrench in order to measure the center conductor depth of beadless airlines with the centering pin removed Care is necessary in selecting a connector gage to measure microwave connectors Some gages have a very strong gage plunger spring strong enough in some cases to push the center conductor back through the connector damaging the device itself Other gages may compress the center con ductor collet in precision 7mm connectors during the measurement giving an inaccurate reading when the collet protrusion is measured Connector gage kits containing gages recommended for microwave connectors and all of the other items required are included in many Hewlett Packard calibration kits and they are also available separately Part numbers are given in Table 1 HP Part Number
439. tion 2 of this manual gives installation instructions for this kit Option 913 Rack Mount With Handles Option 913 is supplied with a kit containing a pair of flanges and the necessary hardware to mount the analyzer with handles attached in an equipment rack with 482 6 mm 19 in horizontal spacing Section 2 of this manual gives installation instructions for this kit Option 910 Extra Operating and Service Manuais The standard instrument is supplied with one manual set one operating manual and one service manual Option 910 provides an additional manual set The manuals are available separately also See Replaceable Parts in the service manual for ordering information ACCESSORIES SUPPLIED Figure 1 1 shows the HP 8757C Option 001 Scalar Network Analyzer with its accessories The HP 8757C E analyzer is shipped with one HP IB cable a power cable and a manual set not shown The power cable supplied depends on the country of destination Section 2 of this manual gives further information about cables connectors and the part numbers for the different power cables Service Accessories A service accessory kit is available for servicing the analyzer This kit consists of 15 pin printed circuit board extender This board is provided for use in troubleshooting the log amplifier assemblies A7 through A10 One special purpose printed circuit board extender This board is provided to aid in troubleshooting the throu
440. tions 1 Adescription of the functions exercised 2 The program listing 3 An explanation of each program line 4 Detailed instructions for operating the program When you finish all of the example programs you will have a good idea of the power of the HP 8757C E when used in an automatic system Note that line numbers aren t required in Microsoft QuickBASIC but are included in the examples for clarity Each line number represents a complete state ment No hard line returns are used in the statements although they may appear that way to improve your ability to read the programs In normal programs an error checking line should follow every call to a subprogram IF PCIB ERR NOERR THEN ERROR PCIB BASERR This statement may be eliminated if this helps program clarity During error trapping if an error occurs the number corresponding to that error is assigned to the variable PCIB ERR PCIB ERR is compared to NO ERR 0 and then branches to a HP IB Command Library subprogram for error handling A message appears on the computer screen stating the error number and type of error SAME CONNECTIONS AS HP8350B HP 83408 HP 8341B j PULSE INPUT TYPE NCHM TO M 8757 SYSTEM INTERFACE POS Z BLANK ee ey HP 8350 HP 8300 41 ONLY ADAPTER BARREL m TYPE N FEMALE DETECTOR TO 8757C E ADAPTER CTYPE N3 MOD DRIVE HP 85027A DIRECTIONAL PAS
441. tor is used to connect the private bus that lets the analyzer control peripherals such as the source plotter and printer Since the analyzer itself controls the 8757 system interface bus other controllers must not be attached to this connector unless the SYSINTF OFF function is engaged The 8757 system interface control of the HP 8350B Sweep Oscillator or HP 8340 or 8341 series Synthesized Sweeper provides frequency annotation shown in the frequency labels area of the CRT in addition the SAVE RECALL and PRESET keys of either the source or the analyzer control these functions in both instruments Alternate sweep capability is also available in both instruments The HP INTERFACE BUS input output connector allows interfacing with a computer controller and other HP IB instruments The POS Z BLANK input connector accepts positive retrace and bandswitch blanking and negative intensity marker z axis modulation signals The signal levels sensed on this input are 5 V for blanking 0 V for display 4 V for markers and 8 V for the active marker The SWEEP IN 0 10V input connector accepts a 0 V to 10 V sweep signal from a source Using the non standard sweep mode it can also accept a different sweep ramp within the 0 to 10 V range The A4 ADC assembly can be modified to allow sweep ramps greater than 4 10 V The STOP SWEEP connector provides the interface signal to stop the sweep of the HP 8350B or 8340 41 when it is controlle
442. tors provide analog red green and blue video signals which can be used to drive an external color monitor such as the HP 3571A B or monochrome monitor such as the HP 35731A B Other analog multisync monitors can be used if they are compatible with the analyzer s 25 5 kHz scan rate and video levels 1 V 0 7 V white 0 V black 0 3 V sync sync on green errare eet ret UAR AT rir eB a atrae m ta ee d rd Mh gata mas rmm rrr S rara peur rsen E HEIN Vetement mar merum ttt Pe errant 11 The LINE V 10 input connector accepts primary line voltage to power the analyzer The line voltage of 100 V 120 V 220 V or 240 V is selected by correctly inserting the printed circuit selector 1 board Information on line voltage and fuse selection is in section 2 Installation 62 Operating Reference HP 8757C E OPERATOR S CHECK DESCRIPTION The operator s check verifies that the analyzer is functioning properly It does not verify all specifica tions but is an appropriate test for daily instrument verification incoming inspection or verification after repair or replacement of digital circuits This check consists of analyzer HP IB and 8757 system interface checks and self tests followed by an insertion loss measurement of a standard device Save the insertion loss data as a reference for comparison with future operator s checks Keep the standard device exclusively for these operator s checks to mini
443. ts cp de reu 9 4 53 HP 8757C Softkey Menu Structure Maps 54 HP 8757E Softkey Menu Structure Maps PEOR T The HP 8757C Rear Panel 61 Equipment Set up for Operator s Check 63 Remote Operation introductory Programming Guide for the HP 8757C E scalar network analyzer with the HP 9000 Series 200 300 Desktop Computer BASIC System Connections 2 The CRT Graphics Display 14 Introductory Programming Guide for the HP 8757C E scalar network analyzer with the HP Vectra Personal Computer using Microsoft QuickBASIC 4 0 System Connections 2 The CRT Graphics Display 17 Table of Contents LIST OF TABLES SECTION 1 GENERAL INFORMATION Specifications and General Requirements 1 8 Supplemental Performance Characteristics 1 10 SECTION 2 INSTALLATION Line Voltage and Fuse Selection 2 2 AC Power Cables Available 2 4 External Modulation Connections s 2 12 SECTION 3 OPERATION Local Operation Operating Reference Status Symbol Identification 6 Minimum Sweep Time Versus Number of Points 13 Display Ranges and Vertical Resolution 14 Scale Per Division for Display Modes 17 HP IB Default Addresses 42 Source S
444. ty 90 at 65 C 149 Protect the instrument from temperature extremes that could cause condensation in the instrument Altitude Up to 15 240 m 50 000 ft PACKAGING Containers and materials identical to those used in factory packaging are available through Hewlett Packard offices A complete diagram of packaging materials used for the analyzer is shown in figure 2 9 See Replaceable Parts for part numbers and ordering information If the analyzer is being returned to Hewlett Packard for servicing complete a blue service tag located at the end of this section and attach it to the analyzer Mark the container FRAGILE to ensure careful handling In any correspondence refer to the analyzer by model number and full serial number Use these instructions to repackage the analyzer with commercially available packaging materials 1 2 If the instrument has rack mount flanges remove them as shown in figure 2 8 Attach a completed blue service tag located at the end of this section if returning the analyzer to Hewlett Packard for service Enclose the analyzer in anti static material Use a strong shipping container Pack enough shock absorbing material around all sides of the analyzer to provide a firm cushion and to prevent movement inside the container Protect the control panel with cardboard Seal the shipping container securely Mark the shipping container FRAGILE to ensure careful handling in any corres
445. ue for detector B External detector cal value for detector External detector cal value for detector R decimal integer 1to9 variable length numeric 0 for ot 1foron unique value ASCII or binary string 23 For more information call your local HP sales office listed in your telephone directory or an HP regional office listed below for the location of your nearest sales office United States Hewlett Packard Company 4 Choke Cherry Road Rockville MD 20850 301 670 4300 Hewlett Packard Company 5201 Tollview Drive Rolling Meadows IL 60008 312 255 9800 Hewlett Packard Company 5161 Lankershim Blvd No Hollywood CA 91601 818 505 5600 Hewlett Packard Company 2015 South Park Piace Atlanta GA 30339 404 955 1500 Canada Hewlett Packard Ltd 6877 Goreway Drive Mississauga Ontario LAVIM8 416 678 9430 Japan Yokogawa Hewlett Packard Ltd 29 21 Takaido Higashi 3 chome Suginami ku Tokyo 168 03 331 6111 Latin America Latin American Region Headquarters Monte Pelvoux Nbr 111 Lomas de Chapultepec 11000 Mexico D F Mexico 905 596 79 33 UJ Australia New Zealand Hewlett Packard Australia Ltd 31 41 Joseph Street Blackburn Victoria 3130 Melbourne Australia 03 895 2895 Far East Hewlett Packard Asia Ltd 22 F Bond Centre West Tower
446. uencies of the measurement 0 01 to 20 GHz The nearest cursor position is calculated and set The value and position of the cursor are read and the actual cursor frequency is calculated from the cursor s position Note The original desired frequency and the actual cursor frequency are usually different Because there are only 401 possible cursor positions some frequencies cannot be set exactly To use more points per trace when using the HP 8757C modify line 90 to be IP SP801 for 801 points Then modify the 400 in lines 180 240 and 280 to 800 Program 5 read a single value Measurements often require that a single value be read at a CW frequency particularly when extremely good frequency accuracy and resolution are required The analyzer is able to read and send a single reading of any measurement channel via HP IB to the computer The OUTPUT VALUE OV command operates on the active channel and causes the analyzer to send one reading of measurement data Even when the analyzer is in normalized mode MEAS MEM the OV command sends the measured not the normalized data Program 5 listing 10 REM SINCLUDE QBSETUP 20 CLS 30 ISC amp 7 40 Snak 716 50 Passthru amp 717 60 CALL IOTIMEQUTCISC amp 10 IF PCIB ERR NOERR THEN ERROR PCIB BASERR 70 CALL IOABORTCISC amp D IF PCIB ERR NOERR THEN ERROR PCIB BASERR 80 CALL IOCLEARCISC amp IF PCIB ERR NUERR THEN ERROR PCIB BASERR 90 A
447. uickly and efficiently as possible it is often necessary to synchronize the source with the analyzer The TAKE SWEEP command gives the analyzer the ability to command the source to make a specified number of complete sweeps 1 to 255 This command is especially useful when using the trace transfer method of reading data from the analyzer To use the TAKE SWEEP command place the analyzer in non swept mode SW0 Then give the TAKE SWEEP command with the number of sweeps desired TSd At the end of the specified number of sweeps the analyzer informs the computer of the completion of this operation by setting a bit in its status byte The computer can detect this event in two ways Monitor the status byte continuously until the bit is set polling Let the analyzer generate a service request SRQ and interrupt the computer Table 1 is a diagram of the status bytes of the analyzer It shows all of the bits that can be used to either monitor or interrupt the computer In this program bit 4 decimal value 16 is used to signal operation complete all of the sweeps specified by the TAKE SWEEP command have been completed When you follow the take sweep command with an output statement such as OUTPUT DATA OD the data is sent immediately not after the instructed number of sweeps The two approaches mentioned overcome this by letting us send the data at the end of the specified number of sweeps not Table 1 NOM Value
448. under both the save and the recall hardkey menus This softkey will allow the user to toggle the state of the CRT graphics off and on To use the graphics off on capability of the analyzer simply change BL5 in line 50 of program 9 to BLA and make the necessary changes in the size of the background grid These changes are illustrated in the following listing The same principle may be used to save to disk anything stored in the first seven pages of user graphics on the ana lyzer By having the softkeys available the user can store CRT graphics onto a disk for later recall Program 11 listing 10 ASSIGN SNA TO 716 20 ASSIGN PASSTHRU to 717 30 ABORT 7 40 CLEAR 5na 50 OUTPUT Sna IP BLA PT15 60 GINIT 70 PLOTTER IS 71 7 HPGL 80 WINDOW 0 2924 0 2047 90 CLIP 0 2700 0 2000 100 OUTPUT gPassthru EP GP1 1 DF 110 PEN 9 120 GRID 100 100 130 PEN 10 140 RESTORE Graphix 150 REPEAT 160 READ Pen_mode X Y 170 SELECT Pen mode 180 CASE D 190 DRAW X Y 200 CASE M 210 MOVE X Y 220 END SELECT 230 UNTIL Pen_mode E 240 MOVE 600 1600 250 OUTPUT Passthru USING K SI0 28 0 34 LBCONNECTION DIAGRAM CHRS 3 260 MOVE 1200 250 270 LABEL DUT 280 LOCAL 7 290 Graphix 300 DATA M 300 800 D 1100 800 Ty 1100 1100 D 300 1100 310 DATA D 300 800 M 800 800 D 800 1100 320 DATA 1500 800 2300 800 2300 1200 0 1500
449. uo teg some tard 45 system cosas dual re e ese 39 SELECT TITLE softkey recall 2254 ee CRA VS 48 SAVE iiy WIRES 45 self calibration 25 self test QRG 7 serialnumber ci TE 1 3 SERVICE key 41 service extended see options Kit cod Gi Merah ant doa es A eee as 1 6 return to HP 2 14 request SRQ 1 11 QRG 6 ON IET 2 14 SET UP DISK softkey recall 2525262 49 SOQVO ius aah sspe gon RES 45 shipment to HP 2 14 SHORTJOPEN softkey 22 short open calibration 22 UG8 signal separation UG 17 1601 softkey see amp TRACE POINTS SLOPE LIMIT softkey 28 SMOOTH APERT softkey 27 SMOOTH ON OFF softkey 27 smoothing 22 UG 14 aperture 27 command QRG 9 softkey menus HP 8757C 54 57 HP G75TE eu wee be 58 60 softkey programming IPG 13 15 software converting RO 1 source requirements 1 9 SPACE softkey 39 SPCL key 27 specifications 1 3 1 8 stable averaging 23 UG 14 START LABEL softkey 39 status bit euet Part ha ne kes QRG 7 cse bee QRG 5 ORG 6 QRG 20 IPG 11 IPV 14 byte commands QRG 14 byte de
450. urce active marker frequencies are shown in this area when a source is connected to the 8757 system interface bus The cursor frequency takes precedence over the active marker Alternate sweep frequencies are also shown when that function is engaged 10 STATUS LINE This line illustrated in figure 4 shows the current status of the analyzer When entries do not apply to the current status they are left blank Operating Reference HP 8757C E cw DETOFS ABCR MANSSNON UNCALABCR _ SYSINTF OFF 3 4 5 6 Figure 4 Status Line Description or DC detection mode 2 Number of trace points 101 201 401 801 1601 3 Non zero detector Offset for each detector indicated 4 Sweep mode other than standard swept mode MAN manual sweep mode CW continuous wave CW sweep mode SS step sweep mode NON nonstandard sweep mode 5 Uncalibrated condition for each detector connected This message occurs only when AUTOCAL OFF is engaged in the CAL menu and an input has drifted out of calibration See HP 8757C E Self Calibration in this section for more information 6 8757 system interface is off 1 HP 8757C only HP 8757C E Operating Reference 7 FRONT PANEL OPERATION CHANNEL Keys ENTRY nm C CJ CJ 3 BOERS OOVE sre Saws Ep eh 007 INSTRUMENT STATE scel sss em Leser E Rr Tarinaa aoh katica z STATUS
451. ure The amount ofa trace in percent on either side of a given pointthat is Saveragag together to perform the smoothing function Array A set of numbers or characters that represents any given function ASGIIE An abbreviation for American Standard Code for Information Interchange A specific format used to transfer information to and from the analyzer or magnetic disk AUX An abbreviation for Auxiliary Refers to rear panel input Binary 1 A method of representing numbers in a scale of two on or off high level or low level one or zero 2 A compact fast format used to transfer information to and from the analyzer or magnetic disk Bit The smailest part of information in a binary notation system Buffer A storage device used to compensate for a difference in the rate of flow of information between two devices when transmitting information Bus One or more conductors used as a path over which information is transmitted from any of several sources to any of several destinations Byte Eight bits of data representing one character processed as a unit Calibration process or operation which removes or reduces measurement errors Checksum A summation of digits or bits primarily used for checking purposes Clamp To limit a signai at a specified level Color brightness A measure of the brightness or intensity of a color Color 1 That aspect of light sources that is caused by differing qualities of the light emitted bos them
452. urrent_line 210 GOSUB Get next token 220 IF Token found lt gt THEN 230 SELECT Token found 240 CASE VAR 250 FOR Counti 1 TO 2 260 GOSUB Remove one word 270 NEXT Counti 280 Intvar 1 VAL Current line 290 CASE BEGIN 300 ALLOCATE Dstring 1 Intvar 1 30 310 ENTER Disk Dstring 320 FOR Count 1 TO Intvar 1 330 Data pt Count1 1 1 VAL Dstring Count1 340 Data pt Count1 2 1 VAL Dstring Count1 POS Dstring Count1 15 350 NEXT Countl 360 Done 1 370 END SELECT 380 END IF 390 UNTIL Done 400 SUBEXIT 410 Get next token 420 Space pos POS Current line 430 IF Space pos 0 THEN 440 Token found Current line 450 Current line 460 ELSE 470 Token found Current line 1 Space pos 1 480 GOSUB Remove one word 490 END IF 500 RETURN 510 Remove one word Current line TRIM Current line jPOS Current line 1 520 RETURN 530 SUBEND 20 Program 12 Explanation Line10 Declare an integer variable and dimension an integer array for use within the program Line 20 Line 30 Dimension a real array for data storage Dimension and reserve memory for the filename string Line40 Prompt for and accept alphanumeric input from the keyboard and place it in the Filename string Line50 Cali the subprogram that reads the file named via line 40 Line 60 Setup a header for the printout of data from the
453. used for quickly reading the measured value of any data point Use the knob to move the cursor across the data When CURSOR is pressed the amplitude of the data point at the active channel cursor position is shown in the CRT active entry area The cursor value for each channelis also shown in the mode labels area The cursor units correspond to the measurement and display mode selected such as dB or SWR The cursor value is always resolved to 0 01 dB 0 001 SWR or 0 001 V If either the HP 8350B Sweep Oscillator or the HP 8340 or 8341 series Synthesized Sweeper is connected to the 8757 system interface bus the cursor frequency for the active channel is shown in the frequency labels area and also in the active entry area If the cursor is off and source markers are on the marker frequency is shown in the frequency labels area When alternate sweep is engaged the cursor frequencies for both sweeps are shown in the frequency labels area CURSOR ON OFF toggles the cursor on or off CURSOR ON OFF toggles the cursor delta function on and off When itis on the A marks the last set position of the cursor When this function is engaged the CURSOR function is automatically toggled on if not already turned on The cursor A function makes it possible to obtain an instant reading of the difference in magnitude and frequency if an appropriate HP IB source is used between two points on the trace marked by the V and the A This magnitude an
454. ut A absolute power measurement Input B absolute power measurement Input C absolute power measurement Input Learn string Initialize disk format Instrument preset Input R absolute power measurement External ADC input AUX voltage measurement Erase limit lines for active channel Load instrument information file from disk Load CRT graphics file from disk Load data trace file from disk Load instrument information file from disk and place instrument in hold mode Load instrument state file from disk Load memory trace file from disk Enter limit test flat line data Store lower limit line into memory 1 HP 8757C only 4 Revision 3 1 or above for an HP 8757C revision 4 1 or above for an HP 8757E 2 HP 8757C Option 001 oniy detector C 5 HP 8340 8341 8360 only with 8757 SYSTEM INTERFACE connected and active 3 Limit line functions valid only for channels 1 or 2 HP 8757C only 6 Revision 3 1 or above for an HP 8757C 24 Table 2 Alphabetical Listing of HP 8757C E Programming Codes 2 of 2 Enter limit test point data Enter limit test sloped line data Limit line test on off Store upper limit line into memory Display normalized data measurement memory Modulation on off Display measurement data Display the channel menu main menu Display normalized data same as M Monochrome display Marker or cursor to reference line Manual
455. utine that outputs commands to the analyzer Line 260 Perform error trapping Line 270 Return from the subroutine Running program 2 1 Press ALT IR N on the computer This clears the previous program 2 Typeinthis program and press ALT R S on the computer 3 The computer presets the analyzer and source and pauses Note the settings of channel 1 and 2 Press ENTER 4 Channeliis turned off Channel 2 is now the active channel notice the highlighted box around the channel 2 mode labels on the analyzer CRT Press ENTER 5 Channel2 scale per division is now set to 10 dB It defaulted to 20 dB div at preset Press ENTER 6 The reference level is set to 10 dBm it was 0 0 dBm Press ENTER 7 The reference position line is set to the center of the CRT graticule 4 The top of the CRT is graticule 8 and the bottom is graticule 0 Press ENTER 8 Change the measurement to reflection input A instead of transmission input B At preset channel 2 defaults to input B Press ENTER 9 Inone statement turn off channel 2 turn on channel 1 set the scale per division to 5 dB set the reference position line to the center of the CRT and set the reference level to 5 dBm NOTE The semicolon terminators are needed after any analyzer command that can have a variable length Extra terminators never hurt so use them liberally Program 3 passthru mode In normal operation the system
456. ution of 0 01 dB Set Detector R offset to d d must bein the range of 60 to 60 dB with a maximum resolution of 0 01 dB Detector Offsets Enter external cal value for the specific detector input d is the code number in the format of DDDDDD read from the front panel after performing a calibration External Detector Calibration Detector DMO Set Detector mode of all inputs for DC detection Mode DM1 Set Detector mode for all inputs for AC detection Adaptive Adaptive Normalization on off Normalization System Perform system configuration calibration of the detectors and channels Calibration TCm 2 Continuous temperature compensation on off CTm 2 Auto System Calibration on off Performs a system calibration at an interval of every five minutes NSm 2 Non standard sweep on off Allows the HP 8757C E to track any sweep ramp in the range of 0 to 10 V increasing in sweep voltage Sweep Mode CW mode single point on off Manual sweep mode on off System Interface control on off P Step sweep mode on off Modulation WE NERONE Rear panel square wave modulation output on off HP 8757C Option 001 only C detector 2 Hfsourceis connected to the 8737 SYSTEM INTERFACE and the interface control is on the source is also set to this mode 3 3 Revision 3 1 or above for an HP 8757C revision 4 1 or above for an HP 8757E 4 HP 8340 HP 8341 and HP 8360 o
457. vides the fastest transfer speed of data and uses the smallest storage space of the two formats available binary and ASCIH The format chosen is hightignted and underlined The analyzer presets to binary format ASCH FORMAT sets the measurement and memory data format to ASCH ASCH format makes the stored data compatible with other computers DISK lets you initialize a disk The analyzer will initialize the disk identified by DISK UNIT and DISK VOLUME Be certain these are correctly set before continuing i i INIT YES begins the initialization The message WAITING FOR DISK appears on the CRT When this message is removed and the disk drive light turns out initialization ts complete NOTE initialization of hard disks can take up to 30 minutes to complete NOTE If your disk is write protected the message WARNING DISK IS WRITE PRO TECTED appears on the CRT and the initialization is aborted If you still wish to initialize the disk remove the write protection and press INIT DISK YES returns the previous menu without running the initialization it will not abort an initialization already in progress PRIOR MENU returns the previous menu Table 6 Source Settings Saved on Disk annn rn ORO Markers 1 through 5
458. y HP 8757C E Modulation Characteristics e f you are using AC detection verify that the modulation frequency of the input signals to the detectors is 27 778 kHz 20 Hz The ON OFF ratio must be at least 30 dB with an ON OFF symmetry of 50 50 5 Sweep Speed Ifthe 8757 system interface is used the analyzer will automatically limit the sweep speed Without the system interface it is the responsibility of the user to ensure proper sweep speed If a problem occurs that is not solved with these suggestions see section 8 of the service manual MISCELLANEOUS PROBLEMS The following paragraphs provide additional information that may clarify some analyzer features Alternate Sweep The alternate sweep feature allows a device to be simultaneously tested over two distinct frequency ranges or power levels In this mode the analyzer displays the alternating sweep conditions at the same time One use for this feature is testing a filter s broadband and passband characteristics simultaneously This is accomplished by alternating the source state between a broadband and narrowband frequency range Another use is simultaneously testing an amplifier in its linear and compressed operating regions This is accomplished by alternating the source state between two different power levels NOTE For the alternate sweep function to operate the analyzer s System Interface must be con nected to the source s HP IB interface Also ensure that the Syste
459. y off 9 Display 45 Seale 52 dBm dB 33 Reference 46 Enter 1 Backspace 17 Cursor 47 Averaging 48 INSTRUMENT STATE Calibration 49 System 51 Special 50 Save 28 Recali 26 Local 29 21 1 HP 8757C only Table9 Alphabetical Listing of HP 8757C E Programming Codes 1 of 2 Averaging off A Bratio measurement A C ratio measurement Averaging on and factor d Adaptive Normalization on off A Rratio measurement Autoscaie Autozero repeat on off of the DC detectors Autozero the DC detectors once B A ratio measurement B C ratio measurement Plotter buffer on off Restore CRT to normal mode Blank frequency labels secure frequency mode frequency labels cannot be restored Blank ail labels Blank active channel trace Blank softkey labels Blank all except user CRT graphics Biank title Biank mode labels Blank the active entry area Blank tHe limit lines Blank all except user CRT graphics and softkeys B Rratio measurement Overall display brightness Display the search bandwidth on the CRT Channel off Channel 1 on active Channel 2 on active Channel 3 on active Channel 4 active C A ratio measurement C Bratio measurement Set channel 1 color Set channel 2 color Set channel 3 color Set channel 4 color Cursor delta on off Set labels color Set background color Set grid color Set warning la
460. yzer through the 8757 system interface bus or when a small RF signal is present in the device under test such as amplifiers mixers and oscillators When the MANUAL softkey is pressed the message REMOVE RF FROM DC DETECTORS appears on the CRT and a second menu layer is presented Disconnect the DC detector from any RF signal CONT is used to alert the analyzer to measure any signal now present at the detector input The analyzer then subtracts this amount from any measurements made The previous menuis automatically presented AUTOZRO is presented in this menu only when a compatible source is connected to the analyzer through the 8757 system interface When AUTOZRO is pressed the analyzer turns off the RF signal from the source and automatically performs the DC detector zero While the autozero is in progress the message AUTO ZERO IN PROGRESS appears on the CRT When completed AUTO ZERO COMPLETED appears on the CRT An autozero can be performed at any time even with the repeat autozero function engaged REPT AZ ON OFF toggles on and off periodic autozero repeats The analyzer is factory set to an interval of 5 minutes REPT AZ TIMER lets you change the interval between autozero repeats Set intervals from 1 to 60 minutes using the numeric keypad Terminate the entry with the ENT key The interval does not change at preset or power on it remains the same until changed with this softkey COARSE ZERO is presented in this
461. zed measurement format with 401 points or fewer The AUX softkey allows the user to measure a voltage inci dent on the ADC IN connector on the rear panel of the analyzer This input voltage must be in the 10 to 10 V range The active channel displays this measurement as volt age versus frequency This function provides a user with the means to measure voltage controlled devices such as atten uators and oscillators enabling the analysis of the device s output power versus the control voltage To access the AUX function select the MEAS hardkey and press MORE until the AU X softkey appears Utilizing cursor and marker functions The CURSOR key activates the cursor on all displayed channels The cursor is identified by a c on an inverted tri angle above each trace it remains the active function until one of the other functions or instrument state keys is selected The cursor value for each trace is presented in the mode label area above the grid How power is presented is determined by the measurement and display mode selected for each channel dB represents the difference between two inputs ratio measurement or current measurement minus the stored reference whereas dBm represents the absolute power at the chosen input Use the front panel knob to move the cursor to the desired location on the trace The measure ment value power and frequency of the active trace will be displayed in the active entry area of the display

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