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1. RF POWER DISPLAY u u dea sua cer een RR Lager exe eren Dex ens LOG c Set up the HP 8642 as follows AMPLITUDE INCREMENT 0 1 dB 2 Set the signal generator level for 6 dB higher than the HP 8642 level 3 Make a reading of the signal level on the measuring receiver Record this reading in the table on the next page Cal 2 Reading Repeat this step for all frequencies and levels in the table on the next page 4 Now compute the Sig Gen Level setting to be used in the SWR Measurement for each frequency in the table Sig Gen Level Step 2a Reading Step 2b Reading 6 HP 8642 level 5 Record sthe setting in the table Sig Gen Level 4 28 Performance Test 8 rev 08JULS88 Model 8642A B Performance Tests Measurement 1 Re connect the instruments as shown in Figure 4 8 Setup A 2 Set the signal generator and HP 8642 frequency to the value listed in the table below 3 4 5 Set the signal generator level to the Sig Gen Level recorded in the table below Set the HP 8642 level to the values given in the table below On the HP 8642 enable the phase increment mode SHIFT SPCL 250 and use the knob to vary the phase the phase of the HP 8642 is varied the readings on the measuring receiver should change Record the maximum and minimum readings on the measuring receiver display in the table below Measurement Readings
2. This key makes RF frequency the active function so its value can be set using either Data keys the Knob Step keys or the Off On key These functions enable relative RF frequency settings These keys enable an RF frequency sweep The sweep modes available are auto manual or single These terminator keys enable you to complete a data entry Figure 3 6 RF Frequency Related Functions 3 38 Model 8642A B Description Operation RF FREQUENCY The Signal Generators fundamental synthesized frequency range of 528 750001 to 1057 500000 MHz is translated over the RF output frequency range listed below The output frequency range is obtained through frequency division and heterodyne conversion and frequency multiplication for the 8642B Table 3 10 RF Frequency Operating Characteristics Electrical m Characteristics Performance Limits Conditions Frequency Range 0 100000 to 1057 500000 MHz 0 100000 to 2115 000000 MHz Underrange 0 000001 to 0 099999 MHz Resolution 1 Hz 0 1 Hz with Special Function 240 or 241 Frequency 85 ms To within 100 Hz Switching Time of final frequency Below 10 kHz the output level drops rapidly The divide bands divide from the fundamental band divide band 9 as shown in Table 3 11 below Although the heterodyne band Het Band covers a frequency range that is included in divide bands 1 through 6 0 100000 to 132 187500 MHz the heterodyne conversion tech
3. 3 14 DATA OUTPUT Hid ee eae aot 3 15 OVERVIEW ooi reete ap seeders 3 15 Output Messages OH OE OC 3 16 Output Active Function OA 3 18 Table 3 4 Output Active Function String Formats 3 19 Output HI LO Status OL 3 20 Output Display Information 3 21 Table 3 5 Output Display Binary Weight of Annunciators 3 22 Table 3 6 Error Code and Message Recovery Example Program 3 23 CLEAR evite vs ai ad ea cete 3 24 Ov rview L T L aus s ane ene entres ete 3 24 REMOTE LOCAL 3 25 Local to Remote Transition 3 25 LOCALS ox dede TS USE eT 3 25 Remote to Local Transition 3 25 LOCAL LOCKOUT SET LOCAL 3 26 Local Lockout z sasa ves qun waqaq 3 26 Clear Lockout Set Local 3 26 SERVICE REQUEST 3 27 OVERVIEW ccelo ieee ey aR 3 27 RQS MASK isc bas 3 27 Clearing the Service Request Message 3 27 Figure 3 4 The Status Byte and ROS Mask upon e es 3 28 STATUS BYTE isi ipee eet ie 3 29 Overview PM 3 29 Reading the Status Byte 3 29 Clearing the Status Byte 3 29 Table 3 7 HP IB Status Byte Bit Definitions 3 30 AD
4. How to Display the Current Frequency Reference REL OFF ne e Bee ees How to Turn Off the Frequency Relative o p x LR nasqa pk ana YS HP IB Codes 5o Comments RF FREQUENCY SWEEP Table 3 12 RF Frequency Sweep Operating Characteristics How to Select Stepped Frequency Sweep SPCL d29 ase ua BS How to Select Phase Continuous Frequency Sweep Special Function 123 START FREQ STOP FREQ How to Set Start and Stop Frequencies How to Stop the Sweep AUTO MANUAL SINGLE How to Select a Sweep Mode TIME How to Set Sweep Time for Stepped Frequency Sweep Using Sweep Time to Set Frequency Step Size and Number of Steps How to Set Sweep Time for Phase Continuous Frequency Sweep Understanding Limitations Between Sweep Spans and Sweep Times Also How to Set a Specific Number of X Axis Steps HP IB Codes Comments Related Special Functions 119 Disable Settling 121 Sweep Up and Down On Figure 3 7 Sweep Waveforms How to Set Sweep Time Operation 3 37 Operation Model 8642A B RF FREQUENCY 86428 SIGNAL GENERATOR 0 1 2100 MHz
5. 3 162 Comments 3 162 Operation Model 8642A B RECALL REGISTERS 360 G3 CC es JOO SHISA OOOOO C 2 These keys enable you to individually save and recall GS Qa sm as front panel settings 0000 This key enables you to sequentially step through the recall registers Figure 3 17 Functions Related to Recall Registers 3 156 Model 8642A B Description Procedure SAVE Operation SAVE RECALL Using the Save function you can save complete instrument states in any of the Signal Generator s 51 recall registers 00 through 50 These registers can then be recalled using the Recall function or the Sequence function Refer to Sequence page 3 161 The recall registers are stored in RAM with battery back up persisting through Instrument Preset and switching the Power from standby to on and unplugging of the ac power cord However if RAM memory is ever lost for example if the battery loses its charge all the recall registers will be lost Table 3 27 below lists those Instrument functions that cannot be saved Table 3 27 Instrument Settings that Cannot Be Saved Messages HP IB Address Local or Remote Mode Sequence Settings Special Functions 3 Service Mode 242 Phase Decrement by 1 Degree 243 Phase Increment by 1 Degree 244 Phase Decrement by 5 Degrees 245 Phase Increment by 5 Degrees
6. wee we DEFAULT VALUE WEIGHT BIT 6 OF THE RQS MASK DOES NOT ENABLE ANY CONDITION THUS IT CAN BE TRUE OR FALSE AND NOT AFFECT RQS SERVICE TURN ON DEFAULT VALUE FOR THE MASK IS BINARY 00000000 REQUEST DECIMAL 0 MESSAGE Figure 3 4 The Status Byte and RQS Mask Model 8642A B Operation Overview Reading the Status Byte Clearing the Status Byte lt gt STATUS BYTE The 8642A B Status Byte consists of one 8 bit byte which reflects Signal Generator status All 8 status bits are updated whether the Signal Generator is in local or remote mode Each bit of the Status Byte monitors a particular aspect of the Signal Generator s operation Table 3 7 HP IB Status Byte Bit Definitions on the following page details the operating conditions which are monitored by the 8642 Status Byte The Status Byte can either be used to cause a Service Request or simply be read to monitor the Signal Generator s operating status To read the Signal Generator s Status Byte the controller must send the Serial Poll Enable bus command and address the Signal Generator to talk For example Program Statement in BASIC 10 S SPOLL 719 If the RQS bit is not set the Status Byte will reflect the current status of the instrument If the RQS bit is set the Status Byte will reflect the status of the instrument when the RQS bit was first set or when the Status Byte was last read with RQS set To actually get the
7. 47 78 52 77 NOTE To compute the actual output impedance Zs 6 100 Actual Zs 4 26 Performance Test 7 rev 08J UL88 Mode 8642A B Performance Tests Performance Test 8 SWR TEST Specification Electrical Characteristics Performance Limits Conditions Description SWR measurement is divided into two parts High Level SWR and Low Level SWR In the High Level SWR Test the HP 8642 frequency is set to the frequency of interest because the ALC loop output impedance is seen directly at the front panel RF output connector This is the only frequency where the HP 8642 output impedance is valid In this test the maximum and minimum of the standing wave are measured directly on a measuring receiver The SWR is computed from the ratio of these two values In the Low Level SWR Test the return loss is measured at each attenuator step for worst case frequencies Return loss is measured by first measuring the power that will be applied to the HP 8642 RF Output This is done through the SWR bridge to calibrate out the loss of the bridge Then the HP 8642 is connected to the SWR bridge and the reflected power is measured The difference between the two measurements is the return loss Note The HP 8642 frequency is set so that it will not interfere with the measurement 10 MHz NPUT MEASUR I NG H B BEB RECEIVER oO apa BB B RF HP 8642A B SYNTHES ZED SIGNAL GENERATOR REFERENCE GENERATOR Figure 4 8 SWR Test Setu
8. 3 102 COT udeg WY apnyjduy UIRUJIXE A Z opnirdury sSurjes INY uo SUONEN I BT E AQEL piuoo WV uoneinpow uon e1ado g VCV 98 POW Operation Model 8642A B Modulation AM cont d Related Special Functions Related Operating Instructions 3 104 113 Modulation Frequency Correction Off This special function disables the single band calibration of the modulation frequency oscillator that normally occurs whenever the modulation oscilator frequency is set or the internal modulation oscillator is put into use When this calibration is disabled the typical modulation frequency switching time is decreased by approximately 200 ms For more information refer to Speeding Up Modulation Switching Time on page 3 132 213 Modulation Frequency Correction On This special function re enables the modulation frequency correction disabled with Special Function 113 248 Calibrate the Modulation Frequency Bands Again This special function enables you to initiate the calibration sequence that normally only occurs during instrument power up This function can be used for example to recalibrate the modulation oscillator frequency bands if normal modulation frequency correction has been disabled with Special Function 113 Calibration typically takes one to two seconds Refer to Modulation Oscillator page 3 131 for more information about the internal modulation oscillator that is the common source for al
9. Repeat phase deviation and distortion tests for the remaining HP 8642 settings PM rad Distortion 0 651 0 909 rad 94 9 105 1 rad 94 9 105 1 rad Performance Test 5 4 19 Performance Tests Mode1 8642A B 4 20 DC FM Center Frequency 1 Preset the instruments 2 On the HP 8642 key in AMPTD 10 dB FM EXT DC 180 kHz 3 On the measuring receiver enable 10 Hz resolution if the measuring receiver is an HP 8902 key in 7 1 SPCL 4 Verify the reading is within the specified limits 100 00000 99 99950 MHz 100 00050 MHz FM Indicated Accuracy 1 Preset the instruments 2 Set the HP 8642 amplitude to 10 dBm 3 Set the measuring receiver to FM mode with all filters off 4 Set the HP 8642 modulation frequency RF frequency and FM deviation to the values given in the table below and verify that the FM deviation readings on the measuring receiver are within the specified limits Results 1 28 2 1 42 kHz 95 0 kHz 105 0 kHz 23 7 kHz 26 3 kHz 177 6 kHz 196 4 kHz 356 2 kHz 393 8 kHz 0 732 kHz 0 830 kHz 5 55 kHz 6 15 kHz 11 1 kHz 12 3 kHz 89 1 kHz 98 5 kHz Performance Test 5 rev 22AUG90 Model 8642A B Performance Tests Incidental AM 1 Set the measuring receiver to AM mode with 50 Hz high pass filter 3 kHz low pass filter and the detector selected 2 On the HP 8642 set FM to Off and set the frequency to 100 1050 and 1300 MHz 1300 f
10. 0 1 dB 1 dB 3 dB lt 100 ms 50 ohms lt 0 75 dB lt 1 5 1 lt 2 0 1 25W 50 55 dBc at 10 dBm Typi cally decreases 10 dB for every 5 dB of combined level decrease For the 8642A Not applicable For the 8642B RF Frequencies of 264 375001 to 528 750000 MHz For the 8642A RF Frequencies of 264 375001 to 528 750000 MHz as well as Heterodyne Band RF Frequencies of 0 100000 to 132 187500 MHz For the 8642B The above Heterodyne Band RF Frequencies For the 8642A Not applicable For the 8642B RF Frequencies of 528 750001 to 1057 500000 MHz For the 8642A RF Frequencies of 528 750001 to 1057 500000 MHz For the 8642B RF Frequencies of 1057 500001 to 2115 000000 MHz Output Amplitude 2 127 dBm into a 50 load Output Amplitude 127 dBm into a 509 load From receipt of controller command Output level 10 dBm Output levels 0 dBm Output levels 20 dBm Two signal generators with frequencies spaced 25 kHz apart into a resistive combiner Absolute levei accuracy consists of allowances for detector linearity temperature flatness and attenuator accuracy rev 19JULY 85 3 69 Model 8642A B Operation Amplitude cont d Procedures Note Put the instrument in its initialized state by selecting ONSTR PRESET AMPTD How to Set the Amplitude Output with the EMF Mode Off You can set the amplitude output by selecting the amplitude function and then setting the
11. Model 8642A B Electrical Characteristics Performance Limits Conditions FREQUENCY MODULATION Cont d Incidental AM Carrier Frequency Offset When Entering FM or PM Modes PHASE MODULATION Maximum Phase Deviation Band 10 8642B only P No G P Q O O T Resolution Indicator Accuracy M Distortion M 3 dB Bandwidth PULSE MODULATION Pulse On Off Ratio Rise Fall Time Maximum Repetition Frequency Minimum Pulse Width Nominal Input Threshold Level INTERNAL MODULATION OSCILLATOR Frequency Range Frequency Resolution Frequency Accuracy Output Level Range Output Level Resolution Output Distortion 20 5 Vpk Output Level Accuracy Output Impedance 200 radians 100 radians 50 radians 25 radians 12 5 radians 6 25 radians 3 125 radians 1 5625 radians 0 78125 radians 6 25 radians 100 radians 0 796 of setting or 0 000496 of maximum deviation whichever is larger 5 of setting 0 09 radians lt 0 4 20 Hz to 15 kHz de to 15 kHz 2509A to 2550A 2551A and above gt 40 dB gt 80 dB lt 400 ns 100 kHz 2 us 1 5V 20 Hz to 100 kHz 1 of setting 2 of setting 0 to 3 3 Vpk 4 mv 0 0296 0 1596 4 15 mV 600 ohms 10 20 kHz peak deviation 1 kHz rate 7400 kHz carrier frequency output level lt 15 dBm ac and internal dc 8642A B Bands 1 9 HET dc 8642B Band 10 1 kHz rate 1 kHz rate Internal and external ac External dc Output le
12. program codes FRKR FRKR FRKR Display I FA FA rA cl i i KI En rA rA fA rm 7 Ti Godne A IM EQ AMPTD x 2 The initialized Knob resolution is 1 MHz at both instrument turn on and Instrument Preset Selecting the right cursor key three times has moved the cursor to the 1 kHz digit Turning the Knob clockwise will now increment the frequency in 1 kHz steps INCR How to Control Knob Resolution by Setting Knob Increment Xnob Increment puts the increment set value on the Knob so you can change a function s value by the increment set values To set an increment set value select INCR SET followed by the desired value Refer to Step Increment Set on page 3 149 To put the increment set value on the Knob KNOB INCR The cursor is displayed above the second letter of the active function s units display when Knob Increment is selected For example if FM deviation is the active function and is set to 900 HZ the cursor is over the Z As you change active functions Knob Increment will continue to remain selected This means that with any active function the Knob will change the function s setting by the increment set value You can turn off the Knob Increment function and all other Knob related functions by selecting ENTRY OFF RE OFF ON You can also turn off Knob Increment alone by selecting one of the cursor positioning keys or 3 142 Model 8642A B Operation
13. 140 NEXTI 150 160 170 OUTPUT 719 SP3657EN DISPLAY THE MESSAGE 180 190 END Example of Reading a User Defined Message Via HP IB You can use the following example BASIC program to read the Message 1 string 10 DIMCS 49 t DIMENSION 49 CHARACTER STRING 20 OUTPUT 719 SP3657EN DISPLAY MESSAGE 1 30 ENTER 719 C READ MESSAGE 1 40 END 3 202 Model 8642A B Appendix B Table 3 30 Special Functions that Can Be Used to Write to the Display Special Functions me Description 653 663 Underline the characters not yet de fined in the message Take out the underlines from the char acters not yet defined in the message Clear the stored message to enable writing another message Get ready to write the next sequential character in the message This special function code is followed by the deci mal equivalent of an ASCII character Output the message This code is used to display the first half of the message This code is also used to output the entire message via HP IB Backspace to the previous character in the message Output message This code is used to display the second half of the message Table 3 31 ASCII Character Codes ASCII Decimal ASCII Decimal ASCII Decimal Character Equivalent Character Equivalent Character Equivalent 32 4 52 H 72 5 N lt xX S lt CHMDVOVOZSrAC mmoodo QoovinAA rev 20MAR 85 3 203 Appendix B Model 8642A B Appendix B Writing
14. 25 to 30 to 85 to 40 to 45 to 50 to 55 to 60 to 65 to 70 to 75 to 80 to 85 to 90 to 60 65 70 75 80 85 90 95 95 to 100 100 to 105 105 to 110 110 to 115 115 to 120 120 to 125 125 to 130 130 to 135 185 to 140 Operation 3 75 Operation Amplitude cont d OUTPUT AMPL I TUDE dBm 4 WHEN ATTENUATOR HOLD 1S SELECTED 0 140 135 130 128 120 115 110 105 100 95 80 85 80 75 70 65 60 55 AVAILABLE AMPLITUDE RANGES dBm um AVAILABLE RANGE AMPLITUDE RANGE AMPLITUDE RANGE OF AMPLITUDE AT WHICH AMPLITUDE IS AT WHICH SPECIFIED AM IS SPECIFIED Figure 3 9 Attenuator Range Hold Amplitude and AM Ranges Model 8642A B Model 8642A B Description Procedures REL ZERO Operation RELATIVE AMPLITUDE A dBm amplitude setting is actually a setting relative to a 1 mW reference even though the 8642A B treats dBm as an absolute amplitude unit With the Relative Amplitude mode the output amplitude can be displayed relative to references other than 1 mW The Relative Zero function sets the current amplitude setting to be the amplitude reference The Reference Set function sets the current display to read as an offset from a specific amplitude reference Setting a value for Reference Set with the Off On key causes
15. External ac or dc coupled M or Internal external ac or dc coupled M 0000067990 NOTE All internal modulation sources use the internal modulation oscillator therefore all internal modulation as well as MOD OUTPUT will have the same modulation frequency 113 Modulation Frequency Correction Off This special function disables the single band calibration of the modulation frequency oscillator that normally occurs whenever the modulation oscillator frequency is set or the internal modulation oscillator is put into use When this calibration is disabled the typical modulation frequency switching time is decreased by approximately 200 ms For more information refer to Speeding Up Modulation Switching Time on page 3 132 213 Modulation Frequency Correction On This special function re enables the modulation frequency correction disabled with Special Function 113 248 Calibrate the Modulation Frequency Bands Again This special function enables you to initiate the calibration sequence that normally only occurs during instrument power up This function can be used for example to recalibraie the modulation oscillator frequency bands if normal modulation frequency correction has been disabled with Special Function 113 Calibration typically takes one to two seconds Refer to Modulation Oscillator page 3 131 for more information on the internal modulation oscillator that 1s the common source for all internal modulation as well as
16. FREQ and amplitude CAMPTD are both key functions Shift key functions are labeled in blue above the key that accesses the function for example REF SET and REL ZERO You can access a shift key function by first pressing the blue CSHIFT key which causes the display to show SHIFT and then the key under the blue label HP IB each shift key function has an individual HP IB code and should not be preceded by a shift code Special functions can be selected by pressing SPCL SHIFT I and then by keying in the code number of the desired special function Refer to Special Functions page 3 16 8 3 199 Appendix Model 8642A B Appendix A Glossary cont d heterodyne band The heterodyne band covers the same frequency range as divide bands 1 through 6 but the heterodyne band allows wider FM and deviation and wider frequency spans for Phase Continuous Frequency Sweep Refer to RF Frequency page 3 39 last selected value A function s last selected value usually can be toggled on with the COFF ON key power up When the instrument is powered up it goes through a sequence of internal checks Refer to Instrument Preset Partial Preset page 3 137 queued up A queued up list is a list of messages that can be accessed when the MSSG key is pressed again and again The MSSG annunciator will indicate when a message 15 queued up for display Refer to Queued Up Messages on page 3 180 RQS RQS re
17. HP IB KHOF USE KNOB UP DN NUMBER Pit The Help function allows you to view the descriptions and code numbers of special functions Select either the Knob Step keys or a function s number RELEASE ALL KEYS P91 Release all keys At turn on it appears that a key is being held down Release all keys to continue If a key is not being held down your instrument may need servicing refer to the Service Manual This message cannot be read via HP IB using Output Display because it automatically clears from the display after the key is released Also HP IB operation is halted when a key is held down with this message displayed 3 196 Model 8642A B Operation Operating Messages cont d Out of Lock Messages The following messages are out of lock messages that might appear as queued up messages during operation These messages will be disabled if Special Function 119 Disable Settling is selected If any of these messages occur the instrument might not be functioning properly and need to be serviced However some of the messages might be displayed because you have exceeded the instrument s limits The out of lock messages are listed in the Table 3 29 Out of Lock Messages on the following page The solution column provides the number s of the solution s listed below that might eliminate the out of lock condition IF THE PRESCRIBED SOLUTION DOES NOT ELIMINATE THE MESSAGE THE INSTRUMENT SHOULD BE SERVICED Also these messages can be o
18. Model 8642A B Data Outpt cont d Table 3 5 Output Display Binary Weight of Annunciators Frequency TLK SRQ FREQ REL Frequency 2 048 4 096 8 192 16 384 32 768 65 536 131 072 262 144 524 288 1 048 576 2 097 152 4 194 304 8 388 608 Example With a display of v I f FA FA FA FA FA FA ITI 7 IKS KI KU el c d t c t kj ui nt Alphanumeric characters output will be 100 000000MZ 140 0DM value output 4th cursor from the left will be 2 16 Annunciator value output for FREQ and AMPTD will be 294229 32 1 048 576 1 048 608 Outputting the display could be used to output the currently selected special functions or to output the annunciator value to determine the current modulation source Table 3 6 Error Code and Message Recovery Example Program 20 85 Model 8642A B UI CAPO PROPJPOPOPOPOTOPO gt cc 000 0 POVONQAQUEWN O OOO UR Wr OOOOOoooooooooooooooooo Operation x Table 3 6 Error Code and Message Recovery Example Program ERROR CODE AND MESSAGE RECOVERY EXAMPLE PROGRAM JWT JULY 1984 EDIT DATE 23 AUG 1984 LET Gen 719 COM Gen_addr Gen I DIM Mssg 74 ENABLE INTR 7 2 ON INTR 7 CALL Get message OUTPUT Gen RM134HZ CALL User I I END f I G et message program SUB PROGRAMM TO POLL THE 8642 AND PRINT THE
19. Power Frequency Range 0 1 to 2115 MHz Power Range 20 to 20 dBm Accuracy 0 2 dB Tuned Power Frequency Range 2 5 MHz to 1300 MHz Power Range 0 dBm to 127 dBm Accuracy 0 5 dB Frequency Resolution 10 Hz Audio Distortion Typical Residual 60 dB Mixer Frequency 0 2 to 500 MHz HP 10514A Type Double Balanced Mixer Frequency 500 to 2115 MHz Watkins Johnson Type Double Balanced M94C Oscilloscope Vertical Sensitivity 10 mV division HP 1980B HP 19860A P A T Bandwidth 100 MHz see Table 1 4 Service Accessory Kit Required for servicing and troubleshooting HP 11801A B C2 See Table 1 5 for parts listing and description Signal Generator Frequency 1 to 2115 MHz HP 8642B Output 50 dBm to 18 dBm see Table 1 4 SSB Phase Noise same or better than the HP 8566A B 1P Performance Testing A Adjustments T Troubleshooting specification for the Generator under test 2HP 11801A services the HP 8642A HP 11801B services the HP 8642B and HP 11801C services both Opt 002 Opt 003 for Optional Residual FM Test Spectrum Analyzer Frequency Range 100 Hz to 6345 MHz Resolution Bandwidth lt 10 Hz Dynamic Range 90 dB 1 15 General Information Model 8642A B Table 1 3 Recommended Test Equipment 2 of 2 Critical Specification Recommended Model Use SWR Bridge Directivity gt 40 dB Wiltron 60NF50 Function Generator Max Ra
20. Reference Loop Module Reference Loop Module Restored Sum Loop Divider Module Sum Loop Divider Module Restored Output Filters ALC Module Output Filters ALC Module Restored Heterodyne Module Heterodyne Module Restored Attenuator Module 8642A Only Attenuator Module Restored 8642A Only Power Supply Regulators Attenuator Drivers Module Power Supply Regulators Attenuator Drivers Module Restored Power Supply Rectifier Filter Module A18 Power Supply Rectifier Filter Module Restored Fuse 5A 250V NTD 1 25 x 25 UL A18F1 Fuse 2A 250V NTD 1 25 x 25 UL A18F2 F4 Fuse 8A 125V NTD 1 25 x 25 UL A18F3 Fuse 25A 250V NTD 1 25 x 25 UL A18F5 Doubler Attenuator Module 8642B Only Doubler Attenuator Module Restored 86428 Only Calibration Module Calibration Module Restored Fan Assembly Fuse 3A 250V NTD 1 25 x 25 UL Adapter BNC to Banana Plug Adapter Coax STR Female BNC to Female SMC Adapter Coax STR Male SMA to Female SMC Adapter Coax STR Male SMC to Male SMC Alignment Tool Screwdriver 075 Bag Anti static 16 X 0 inch Opening Bag Anti static 4 x 0 inch Opening Bit Torx T10 Bit Torx T15 Bit Torx T5 Cable Assembly Short Cable Assembly Service Kit Long Cable Tie 062 625 Dia 091 Wd Nylon 1 17 General Information 1 18 Model 8642A B Table 1 5 HP 11801C On Site Service Kit 2 of 2 HP Part m Reference wa aunty Dessin etn 11801 90201 11801 90203 1251 8601
21. 3 Set the audio analyzer filters off 4 Set the audio analyzer s input coupling to FLOAT Level Accuracy 1 Set the HP 8642 modulation frequency and modulation output level to the values given in the table below 2 Verify that the readings are within the specified limits Results 0 020 kHz 1 000 kHz 100 0 kHz 0 020 kHz 1 000 kHz 100 0 kHz Use the audio analyzer 30 kHz low pass filter at these points Frequency Accuracy 1 Set the HP 8642 modulation frequency to the values given in the table below 2 Verify that the frequency indicated on the audio analyzer is within the specified limits MOD wes 20 0 Hz 14 9 kHz 15 1 kHz 100 0 kHz reu 08J UL88 Performance Test 7 4 25 Performance Tests Mode 8642A B Distortion 1 Change the audio analyzer mode to distortion 2 Set the HP 8642 modulation frequency and modulation output level to the values given in the table below 3 Verify that the readings are within the specified limits OUT rS 0 020 kHz 15 80 kHz 100 0 kHz 0 020 kHz 15 80 kHz 100 0 kHz Use 30 kHz low pass on audio analyzer Remove low pass filters Output Impedance 1 Set the HP 8642 MOD FREQ to 1 kHz 2 Set the audio analyzer to AC level and ratio 3 Terminate the HP 8642 MOD OUTPUT with the 600 ohm Figure 4 7 feedthrough and re connect the cable Figure 4 7 Setup B 4 Verify that the audio analyzer reading is within the specified limits
22. 53 0 dBEMFuV dBm 113 0 V 19 dBm 13 0 20 mV jo dBm 47 0 20 uV 0 9 107 0 20 EMF V jo dBm 7 0 20 EMF mV o dBm 53 0 20 EMF uV 10 4 113 0 20 3 206 20 85 Model 8642A B Appendix D Appendix D DISPLAY ANNUNCIATORS AND ABBREVIATIONS RMT LSTN START TLK SRQ FREQ REL EMF SPCL SWPNG HILO MFM START iNT EXT AMPTD REL STOP MSSG The front panel display annunciators usually indicate the state of the Signal Generator that is they indicate which functions are currently affecting the output Each of these annunciators are listed in the order they appear in the display The explanations below describe the purpose of each annunciator RMT LSTN TLK SRQ These annunciators indicate the HP IB status of the Signal Generator START The START annunciator in the left portion of the display indicates that RF frequency sweep is selected and a start frequency is currently displayed FRE This annunciator indicates the RF frequency is being displayed The REL annunciator in the left portion of the display indicates the current RF frequency is displayed in relative units When EMF is displayed amplitude is in EMF units SPCL When SPCL is displayed a special function is currently selected During normal instrument settings display SWPNG indicates that either an RF frequency or amplitude sweep is currently taking place 3 HI and LO can be used to indicate whether the exte
23. CSHIFT CNT the decimal equivalent of the binary 8 bit byte and any terminator such as HZ UV Example Enable status bits 0 End of Sweep 1 Hardware Error and 7 Parameters Changed to cause a service request SRQ bus line true by unmasking those bits that is set the Signal Generator s RQS mask to binary 1000001 1 decimal 131 Set the mask value to binary 10000011 decimal 131 Local operation RQS MASK CSHET CNT C1 C3 CT CHZ UV Remote operation RM 131 HZ A Service Request can be generated in either the local or remote mode To determine which status bit caused the service request refer to Table 3 7 HP IB Status Byte Bit Definitions on page 3 30 The Status Byte can be read only by doing a serial poll via HP IB refer to page 3 29 Service Request Message The Service Request message can be cleared by masking the set bits in the Status Byte using the RQS mask If the condition which caused SRQ to be pulled has been resolved the Service Request message can be cleared with any of the following actions for clearing the Status Byte Sending Clear Status CS Sending Instrument Preset IP Sending Device Clear or Selected Device Clear Switching Power from Standby to On Resetting the individual set bits Refer to Table 3 7 on page 3 30 3 27 Operation Model 8642A B x CONDITIONS Y PARAMETER LOCAL EXECUTION HARDWARE ERROR READY REMOTE ERROR ERROR 2 STATUS BYTE
24. Display v Ida dad Z Hdr Z FREQ FM EXT AMPTD The RF output is being externally frequency modulated with an external dc coupled source as indicated by the FM EXT and DC annunciators FM deviation setting is 80 0 kHz per volt Modulation frequency is not monitored by the Signal Generator when an external modulation source is used The cursor above the FM setting indicates FM is the active function INT EXT DC MOD FREQ OFF ON FMOF FMON INT EXT AC EXT DC INT EXT AC MHz kHz Hz SPCL External Modulation External modulation frequency is not monitored by the Signal Generator Therefore if the external FM source violates the maximum deviation relationships shown in Table 3 20 on page 3 112 the Signal Generator will be operating beyond its specified limits and could lose phase lock which causes queued up Hardware Error messages Modulation Types Not Possible During RF Frequency Sweep During Stepped Frequency Sweep FM and 9M are allowed in manual or single sweep mode only During Phase Continuous Frequency Sweep Special Function 123 all modulation types are possible Model 8642A B Operation Modulation FM cont d Spurious Signals Spurs That Occur with the Internal Source Internally generated spurs with levels specified less than 100 dBc might be present when the internal modulation oscillator is in use These spurs will be eliminated when no internal modulation source is modulating t
25. SHIFT AM J EXT DC J Adjust the external modulation signal to a level above 1 5 volts Above 1 5 volts the output is on and below 1 5 volts the output is off Pulse repetition rate and duty cycle are determined by the external pulse generating source Note that the HI LO annunciators are not used for pulse modulation NOTE External modulation freqency is not monitored by the Signal Generator The Signal Generator s modulation frequency display refers to the internal modulation oscillator only 3 128 20 85 Model 8642A B Operation Modulation Pulse cont d Example HP IB Codes Comments Pulse modulate the RF output with an external dc coupled source at a rate and duty cycle determined by the external source starting with pulse modulation off a ENTRY MODULATION SOURCE LOCAL program PLXD PLON codes Display Ti LSE iHi Dm FREQ EXT DC a The RF output is being externally pulse modulated with an external dc coupled source as indicated by the word PULSE and the annunciators EXT and DC the cursor above the pulse modulation display indicates that pulse modulation can be toggled off and on by selecting the COFF ON key Modulation Restrictions with other Functions Pulse modulation and AM are not possible during amplitude sweep Also AM and pulse modulation are not possible when ALC Off Special Function 4 is selected Spurious Signals
26. 125 9E 06 12 59E 06 1 259E 06 125 9E 09 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 125 9E 15 12 59E 15 1 259E 15 251 2E 18 2 3 On the HP 8902A Measuring Receiver press blue SHIFT STORE followed by the numeric key indicated by the note number Performance Test 1 rev 08JUL88 Model 8642A B Performance Tests Measuring i Results watts HP 8642 5642 FREQ Receiver Measuring RF POWER 79 43E 03 125 9E 03 RF POWER 7 762E 03 12 30E 03 RF POWER 2 510E 03 3 981E 03 TUNED RF 794 3E 06 1 259E 03 TUNED RF 79 43E 06 125 9E 06 TUNED RF 7 943E 06 12 59E 06 TUNED RF 794 3E 09 1 259E 06 TUNED RF 79 43E 09 125 9E 09 TUNED RF 7 943E 09 12 59E 09 TUNED RF 794 3E 12 1 259E 09 TUNED RF 79 43E 12 125 9E 12 TUNED RF 7 943E 12 12 59E 12 TUNED RF 794 3E 15 1 259E 12 TUNED RF 79 43E 15 125 9E 15 TUNED RF 7 943E 15 12 59E 15 TUNED RF 794 3E 18 1 259E 15 TUNED RF 158 5E 18 251 2E 18 TUNED RF AMPTD r quenc Receiver dBm Mode RF POWER 63 09E 03 RF POWER 50 12E 03 RF POWER 7 762E 03 RF POWER 2 510E 03 100 0E 03 79 43E 03 12 30E 03 3 981E 03 TUNED RF 794 3E 06 TUNED RF 79 43E 06 TUNED RF 7 943E 06 TUNED RF 794 3E 09 TUNED RF 79 43E 09 TUNED RF 7 943E 09 1 259E 03 125 9E 06 12 59E 06 1 259E 06 125 9E 09 12 59E 09 TUNED RF 794 3E 12 TUNED RF 79 43E 12 TUNED RF 7 943E 12 TUNED RF 794 3E 15 1 259E 09 125 9E 12 12 59E 12 1 259E 12 TUNED RF 79 43E 15 TUNED RF 7 943E 15
27. 2 7 Model 8642A B Operation Section 3 OPERATION INTRODUCTION TO SECTIdIN The information in this section describes both general and specific operation of the HP 8642A B If you have no experience with the Signal Generator you should first read Operating Fundamentals included with this Volume I as a separate booklet which is intended only as a familiarization guide Although this Section IH can be used to learn basic operation you might feel there is more information here than you need After you read Operating Fundamentals you can use this Operation Section for additional information Figure 3 1 in Operating Information page 3 3 is a graphic representation of the Signal Generator s basic operation This figure shows most of the keys that you use to operate the instrument Similar diagrams that show more specific functions and their associated keys are available on pages 3 34 3 38 3 68 3 96 3 136 3 156 3 166 and 3 178 Figure 3 2 on page 3 4 shows rear panel features The major functions of this section are grouped as follows Operating Information HP IB Remote Operation Detailed Operating Instructions RF Frequency Amplitude Modulation Setting Modifications Recall Registers Special Functions Messages Appendixes Index OPERATOR CHECKS Since the Signal Generator performs self checks no operator checks are necessary However extensive self diagnostics are available Refer to the Service Section Volumes 2 th
28. 3 FA FA FA TA ITI 7 2 fA Ti ITI e dd dd Z HE i FREQ AMPTD Frequency has been set to 1 230000 MHz The cursor above the frequency display setting indicates frequency is the active function SPCL 8 How To Select the Het Band Special Function 8 Either you can select the Het band or the Signal Generator will select Het band operation as described below Selecting Special Function 8 configures the instrument to operate in the Het band whenever the RF frequency is less than 132 187501 MHz regardless of FM or M deviation or Phase Continuous Frequency Sweep span SPCL CSHET W Turn off Special Function 8 SPCL CSHFT 2 C2 CO 8 The Signal Generator will automatically select the Het band if you select a combination of RF frequency and FM or deviation or a Phase Continuous Frequency Sweep span beyond the capabilities of the Signal Generator s divide bands The Signal Generator automatically switches back to a divide band when the combination of functions selected allow divide band operation unless the Het band is selected with Special Function 8 Example Configure the Signal Generator to operate in the Het band at frequencies less than 132 187501 MHz regardless of FM or deviation or Phase Continuous Frequency Sweep span settings x program Display After entering SPCL 8 the Signal Generator displays the number and description of the Special Function just entered To
29. 3 121 HP IB Codes 3 123 Comments aS es 3 123 Related Special Functions 3 124 7 Low Distortion On 3 124 113 Modulation Frequency Correction Off 3 124 114 Negative Polarity 3 124 119 Disable Settling 3 125 248 Calibrate the Modulation Frequency Bands Again 3 125 MODULATION PULSE 3 127 PULSE oue DERE er uere a 3 127 Table 3 23 Pulse Modulation Operating Characteristics 3 127 INT oie he ee RO MP UTE MU eed 3 127 How to Set Pulse Modulation with the Internal SOUIGCe ai 3 127 EXT AC EXT DC is sce Rem 3 128 How to Set Pulse Modulation with an External SOUICe n b eb eel 3 128 HP IB Codes ee 3 129 Comments z sau SY iu sees 3 129 Related Special Functions 3 130 113 Modulation Frequency Correction Off 3 130 248 Calibrate the Modulation Frequency Bands Again 3 130 MODULATION OSCILLATOR 3 131 Table 3 24 Modulation Oscillator Operating Characteristics 3 131 MOD FREQ vss 3 131 How to Set Modulation Frequency 3 131 MOD OUT oret ees ce re etes 3 131 How to Set Modulation Output Level 3 131 HP IB Codes shew iA s 3
30. 93 8 kHz or f o4 X 67 9 band 1 rev 08JUL88 Performance Test 5 4 15 Performance Tests Model 8642A B Electrical Characteristics Performance Limits FREQUENCY MODULATION Cont d Maximum Peak Deviation 3 MHz band 10 dc coupled 1 5 MHz band 9 HET 750 kHz band 8 375 kHz band 7 187 kHz band 6 93 8 kHz band 5 1 46 9 kHz band 4 23 4 kHz band 3 11 7 kHz band 2 93 8 kHz band 1 1 5 MHz band HET Indicator Accuracy 5 of reading 10 Hz Rates lt 100 kHz FM Resolution The larger of 0 7 of setting or 0 0004 of max deviation Incidental AM 0 30 20 kHz deviation 1 kHz 1 kHz rate rate gt 400 kHz carrier FM Distortion 0 496 1 15 max dc coupled deviation Rates 20 Hz to 100 kHz 2 096 1 2 max dc coupled deviation 4 096 max dc coupled deviation Frequency Offset None internal and ac When entering FM or mode lt 500 Hz dc 1 kHz dc band 10 PHASE MODULATION Maximum Peak Deviation 200 radians band 10 100 radians band 9 HET 50 radians band 8 25 radians band 7 12 5 radians band 6 6 25 radians band 5 1 3 13 radians band 4 1 56 radians band 3 0 78 radians band 2 4 16 Performance Test 5 rev 08JUL88 Model 8642A B Performance Tests Electrical Characteristics Performance Limits Conditions PHASE MODULATION Cont d Indicator Accuracy 5 of reading 4 0 9 rad 1 kHz rate Resolution The larger of 0 7596 of setting or 0 000496 of max deviation Distortion 1 kHz rate 0 4
31. Data keys or the Off On key if applicable 3 147 Model 8642 Description Procedures INCR SET Operation STEP INCREMENT SET The values of Signal Generator functions can be stepped up or down by an increment set value using the Step keys t or C J The Signal Generator powers up with default increment set values for all functions that allow increment set Refer to Table 3 26 below You can select a desired increment set value up to the listed maximum The Signal Generator returns to default increment values if the Pov s switched from standby to on or if Instrument Preset is selected You can also use the Step keysin ollowing ways When saving or recalling suc registers Refer to Save Recall page 3 1 57 When stepping through the listing Refer to Special Functions page 3 167 When incrementing the p of the RF frequency using Special Function 250 Refer to RF Frequency p _ 42 Tabie 3 26 Increment Set Values Default Maximum Increment Increment RF Frequency 10 MHz 2115 MHz AM Depth 10 99 9 FM Deviation 5 kHz 3 MHz Deviation 0 1 radians 200 radians Modulation Frequency 1 kHz 100 kHz Modulation Output Level 100 mV 3 3V Amplitude 1 dB 160 dB 2 24V 4 49 EMFV Start Stop Amplitude 1 dB 160 dB Start Stop Frequency 10 MHz 2115 MHz Sweep Time 100 ms 999s Note Put the instrument in its initialized state by selecting
32. FM HZ RT FRQ P FRQ TIME cs guapo S PO lt 3 208 start amplitude stop amplitude AM amplitude modulation amplitude off dB dBm external modulation source FM frequency modulation Hz internal modulation source KHz modulation frequency modulation output level milliradians ms milliseconds mV millivolts MHz 45 percent pulse modulation M phase modulation radians s seconds sequence start frequency stop frequency sweep time microradians uV microvolts V volts rev 20MAR 85 Model 8642A B Appendix E APPENDIX E INDIVIDUAL INSTRUMENT IDENTIFICATION The instrument s mode number seria number and the options installed in the instrument can be displayed on the front panel or read through HP IB Service Special Function 40 accesses the model number of the instrument Service Special Function 41 accesses the serial number and Service Special Function 42 lists the options installed in the instrument Note that accessing service special functions is different than accessing the user special functions discussed previously in this manual manually select user special functions you key in SPCL and then the special function number To manually select service special functions you need to follow two steps For HP IB use the HP IB example below 1 First select user Special Function 3 Service Mode with keystrokes SPCL O 2 After you enter the service mode
33. For more information refer to Speeding Up Modulation Switching Time page 3 132 213 Modulation Frequency Correction On This special function re enables the modulation frequency correction disabled with Special Function 113 114 Negative M Polarity This special function causes a positive voltage applied to the external FM M INPUT to cause a phase lag and a negative voltage applied to cause a phase lead 214 Positive Polarity This special function causes a positive voltage applied to the external FM M INPUT to cause a phase lead and a negative voltage applied to cause a phase lag 119 Disable Settling This special function allows the Signal Generators microprocessor to respond to new commands without waiting for the internal circuitry to settle When using this special function it s possible to select a function before the previous function has finished settling When settling is disabled response time is improved by up to 40 ms Special Function 119 disables out of lock messages 219 Re enable Settling This special function re enables the settling that is disabled when Special Function 119 is selected 248 Calibrate the Modulation Frequency Bands Again This special function enables you to initiate the calibration sequence that normally only occurs during instrument power up This function can be used for example to recalibrate the modulation oscillator frequency bands if normal modulation frequency correction has bee
34. HELD DESIRE PM ON ATTENUATOR RANGE PM MODULATION SOURCE 2 MODULATION AP DATA UNITS SOURCE 1 FR DATA UNITS DESTRE SPS NO ON FOR THIS AP SETTING DESIRE PM ON DESIRE SP6 FINISHED DESIRE AM ON AM DATA UNITS MODULATION SOURCE OF CFinisHeo 91122 09 SP112 MF DATA UNITS IS FM DESIRED WITH FR DATA UNITS DESIRE FM ON 1FM Modulation Sources include FMNT FMXA FMXD FMBA FMBD SP5 SP112 26M Modulation Sources include PMNT PMXA PMXD PMBA PMBD Figure 3 3 Flowcharts for Sequence Dependency Operation x Model 8642A B Data Input cont d Valid Character Entry Exceptions to Flowcharts Not covered in those flowcharts is frequency sweep s dependence on entry sequence Frequency sweeps are coupled to FM and settings When selecting either Digitally Stepped Frequency Sweep or Phase Continuous Frequency Sweep with either FM or M use the following sequence 1 Turn off frequency sweep FAOF FBOF 2 Select either Special Function 123 Phase Continuous Frequency Sweep or Special Function 223 Phase Continuous Frequency Sweep Off which enables the selection of Digitally Stepped Frequency Sweep If FM is to be selected use the FM flow chart but don t set FM yet nor FR If M is to be selected use the flow chart but don t set PM yet nor FR With Start Frequency FA or Stop Frequency FB active select the sweep mode FASA for auto FASM for manual or FAS
35. How to Reference to the Signal Generator s Last Selected Reference Turn on the amplitude relative mode by setting the amplitude reference to the last selected value CAMPTD REFSET CSHFT CFREQ OFF ON How to Display the Current Reference CAMPTD REF SET SHET TED Even though the amplitude reference can be set in dB relative units using the Relative Zero function the amplitude reference can only be displayed in absolute units In this case the amplitude setting is automatically converted to absolute units before it is set as the amplitude reference Clear the reference display by either pressing the key twice or by setting another function Model 8642A B Operation Relative Amplitude cont d REL OFF How to Turn Off the Relative Mode HP IB Codes Comments CAMPTD REL OFF HEID FEON or CAMPTD REFSET CSHET FREQ COFF ON or Select a volts key with amplitude as the active function volts units are always absolute REF SET REL ZERO REL OFF AMPTD OFF ON APRSOF APRSON EMF EMON EMOF Range of Amplitude Reference Settings Allowable ranges for the amplitude reference settings 59 9 dBm to 140 dBm 4 995V to 0 023 uV 9 99 EMF V to 0 046 EMF uV Note that the maximum for the dBm setting is greater than that for the voltage setting If you want to set a higher voltage reference than 4 995V 9 99 EMF V convert the value to dBm and set the reference set value as high as
36. Knob cont d Example of Controlling Knob Resolution by Setting Knob Increment Use the Knob to increment frequency by 25 kHz per step FRIS 25 KZ KI program codes Display v FATA TA TA iTi 7 Ti iDndumndddudnz FREQ AMPTD Knob resolution has been set with the Knob Increment function as indicated by the cursor over the Z Turning the Knob will step frequency in 25 kHz steps HOLD How to Use Knob Hold to Maintain Control of a Function s Value When Another Function Is Active Knob Hold is a way to maintain Knob control over one function while acquiring the ability to change another function s value with the Step and Data keys and the Off On key Knob Hold can be turned on by Selecting the desired active function then HOLD SHIFT COFF ON Knob Control is held on the selected function as indicated by the two cursors over that held function Selecting a different function key sets that different function as the active function which can be acted on only by the Step keys or Data keys or the Off On key Knob control does not transfer to this new active function but stays with the function that was active when Knob Hold was selected During Knob Hold a function with just one cursor is not controlled by the Knob the function having two cursors is controlled by the Knob Turn off Knob Hold by selecting Knob HOLD SHET Co OFF ON Knob Hold along eith all other Knob related funct
37. Specifications part of 3 of 6 Electrical Characteristics Performance Limits Conditions FREQUENCY MODULATION Maximum FM Deviation External dc coupled Band 10 8642B only 3 MHz 1 5 MHz 750 kHz 375 kHz 187 5 kHz 93 75 kHz 46 875 kHz 23 437 kHz 11 718 kHz 93 75 kHz T 1 5 MHz the smaller of External ac coupled or internal 10 8642B only 3 MHz or faoa X 2160 1 5 MHz fmog X 1080 750 kHz or fmog X 540 375 kHz or frog X 270 187 5 kHz or f 4 X 1359 93 75 kHz or fmog X 67 58 46 875 kHz or fmog X 33 759 23 437 kHz or f X 16 8759 11 718 kHz or f 4 X 8 43759 93 75 kHz fmog X 67 59 T 1 5 MHz or fmoa X 1080 Resolution 0 7 of setting or 0 0004 of maximum deviation whichever is larger Indicator Accuracy 5 of setting 10 Hz Rates 20 Hz to 100 kHz FM Distortion 4 For maximum dc coupled deviation Rates 20 Hz to 100 kHz 2 For 1 2 max dc coupled deviation 0 496 For 1 15 max dc coupled deviation FM 3 dB Bandwidth dc to 200 kHz External dc source 20 Hz to 200 kHz External ac source 20 Hz to 100 kHz Internal source N gt 0 O Pi no gt G O I O 6Maximum deviation may be increased up to that shown for the HET band 0 1 MHz to 132 1875 MHz carrier frequency by selecting deviation larger than the values shown here HET band can also be selected with Special Function 8 07 0 85 1 9 General Information Table 1 1 Specifications 4 of 6
38. Subtract the Maximum from the Minimum reading in and record the Result in the table below Results Max Min Verify that the actual result is less than the specified Maximum Measurement Results Frequency Cal 1 Cal 2 Readings Max Min Gen MHz Reading Reading Max Actual Maximum 4 000 4 000 4 000 4 000 1000 000 1000 000 1000 000 1000 000 2000 000 2000 000 2000 000 2000 000 NOTE If actual SWR values are needed compute SWR using the following formula SWR 10 maz min in dBm 20 Low Level SWR rev 08J UL88 Connect the instruments as shown in Figure 4 8 Setup B Preset the instruments Set the Signal Generator to ADD ED 16 dBm FREQUENCY eA erre dere aee REVISE erede 4 MHz Performance Test 8 4 29 Performance Tests Model 8642A B 4 Set the HP 8642 to PREQUENCUYS cite aan ane 500 MHz 5 Set up the measuring receiver as follows DISPLAY MOD Bese aa lp au GAS Wek rere sie SERS Ga ATO Ae UNS LOG Low Level SWR Reference 1 Set the Signal Generator and measuring receiver frequency to values listed in the table below 2 Measure the Ref at all settings and record each reading under Intermediate Readings Ref Low Level SWR Reflection 1 Connect the instruments as shown in Figure4 8 Setup A Preset the instruments Put the measuring receiver in RF POWER mode Set the HP 8642 to the levels lis
39. as additional information rev 30SEP88 1 1 General Information Model 8642A B 1 3 WHERE TO FIND SAFETY CONSIDERATIONS This product is a Safety Class I instrument that is one provided with a protective earth terminal Before operating or servicing the Signal Generator service personnel should familiarize themselves with the safety markings on the Signal Generator and the safety instructions Safety information pertinent to the task at hand that is information regarding installing operating performance testing adjusting or servicing the HP 8642A B is found throughout this manual Refer to the Safety Considerations pages found at the beginning of Volume 1 for a summary of that information 1 4 HEWLETT PACKARD INTERFACE BUS HP IB ENABLES REMOTE CONTROL OF THE INSTRUMENT TZ The HP 8642A B Signal Generator has a Hewlett Packard Interface Bus HP IB interface and can be used with an HP IB compatible controller for test system applications The Signal Generator is fully programmable via the Hewlett Packard Interface Bus HP IB is Hewlett Packard s implementation of IEEE Standard 488 and the identical ANSI Standard MC1 1 Refer to the HP IB portion of Section 3 for more complete details Selecting the HP IB Address The Signal Generator s HP IB address is set to 19 at the factory in both internal memory and an internal switch located inside the instrument The decimal equivalent of the 5 bit address code can be displayed on and ch
40. modulation oscillator frequency and its individual frequency band are recalibrated to correct for inaccuracies due to changes in temperature Modulation Frequency Correction A single calibration of all modulation oscillator frequency bands can be initiated using Special Function 248 If faster switching between modulation frequencies is desired Modulation Frequency Correction can be disabled by selecting Modulation Frequency Correction Off Special Function 113 This special function decreases switching time by approximately 200 ms Automatic modulation frequency correction can be re enabled by selecting Model 8642A B Operation Modulation Oscillator cont d Special Function 213 When modulation frequency correction is disabled the Signal Generator does not automatically recalibrate at each modulation frequency wnen one is selected Instead the instrument uses as its calibration data the previously calculated calibration factor for each frequency band The accuracy of previously calculated calibration factors depends on variations in temperature from the time the calibration factor was selected Typically 2 accuracy can be degraded to 5 if recalibration is not performed when the Signal Generator is subjected to temperature changes of 50 C DC FM Update Mode Special Function 117 also increases modulation frequency switching by up to 200 ms Refer to Special Function 117 description in Modulation FM on page 3 116 Spurious Sign
41. modulation signal by configuring the Signal Generator to output the status of the HI LO annuciators for AM FM The status can be read as either a numeric value or as a string that represents the HI and LO annunciators Annunciator Numeric Value String Representation Representation HI 1 HI LO LO neither HI nor LO 0 OK Following is a programming example in BASIC for outputting HI LO status OL Output from the Signal Generator address 19 the status of its HI LO annunciators for an external ac coupled AM signal To output the numeric value 10 OUTPUT 719 AMOL 20 ENTER 719 V To output the string 10 OUTPUT 719 AMOL 20 ENTER 719 V Dummy read of the numeric value 30 ENTER 719 A Model 8642A B Operation Output Display Information rev 20MAR amp 83 lt The Signal Generator will output the display information when it is addressed to talk and is not configured to output any other data 1 The first time the Signal Generator is addressed to talk it will output the actual display in alphanumeric characters maximum of 74 characters The string length of the alphanumeric display will always be greater than or equal to 25 characters 2 The second time the Signal Generator is addressed to talk it will output a number representing the displayed cursor positions in a binary weighted sum This string length will always be less than 25 characters 3 The third time the Signal Generator i
42. page 3 66 or Figure 3 10 Sweep Waveforms in Amplitude Sweep page 3 93 122 Linear Amplitude Sweep This special function selects a linearly stepped output rather than the usual logarithmicly stepped output Use a sweep time greater than 900 ms to obtain maximum sweep resolution 123 Phase Continuous Frequency Sweep Phase Continuous Frequency Sweep enables the Signal Generator to frequency sweep between two end points in a linear phase continuous manner Refer to RF Frequency Sweep page 3 49 134 Turn Off LCD Lighting This special function turns off the LCD back lighting in the display 135 Disable Display Special Function 135 causes the Signal Generator to execute commands without displaying the instrument state useful in secure environments 204 Disable ALC Off This special function re enables the output leveling loop that was disabled with Special Function 4 205 External Low Rate FM Off This special function turns off the FM modulation source selected with Special Function 5 When Special Function 5 is turned off in this way the Signal Generator selects external ac coupled FM 206 FM Pre Emphasis Off This special function turns off the pre emphasis selected with Special Function 6 207 Low Distortion Off This special function switches out the shaper circuitry inserted with Special Function 7 208 Prefer Divide Bands This special function re enables the automatic preference of selecting the divide
43. the Signal Generator explains the restriction Execution Error messages occur immediately after executing a command that does not execute HP IB You can read only the first Execution Error message if more than one has occurred For example assume that more than one Execution Error message has occurred since either the Status Byte was cleared or since the last time OE was executed Then reading an Execution Error message using OE will enable you to read out only the first message NEXT STEP NOT POSSIBLE 1 4001 Next step is not possible The current setting cannot be stepped up or down as attempted with the increment set value To clear the message without changing instrument settings select the SHIFT key twice If you want to read a message that might more specifically describe the setting problem attempt a data setting similar to the step attempt that caused this error message NOT POSSIBLE ABOVE MAX E2 4002 Not possible above the maximum setting ever allowed The attempted setting is above the function s maximum possible setting independent of other functions NOT POSSIBLE BELOW MIN E3 4003 Not possible below the minimum setting ever allowed The attempted setting is below the function s minimum possible setting independent of other functions SELECT MOD PREFIX FIRST E4 4004 Select the type of modulation first A modulation source was selected when a modulation setting was not displayed Before selecting the modulation so
44. you can select the service special function number followed by the terminator The instrument only knows you have selected a special function when you key in the terminator To list Model number of the instrument SPCL 3 4 0 Serial number of the instrument SPCL DJ 3 4 1 Options installed in the instrument SPCL SHIFT 3 4 2 High Stability Time Base Option 001 HP 8642A B Rear panel connectors Option 002 HP 8642A B New attenuator A16 serial prefix 3005A and above HP 8642A not an option Internal firmware code not an option HP 8642A HP IB Example in BASIC The listing below is an example of reading the list of installed options via HP IB using Output Display which is described in Data Output page 3 21 Note that the terminator for a service special function is EN When in the service special function mode EN is the programming equivalent of manually pressing the Hz key 10 DIM AS 74 20 OUTPUT 719 SP342EN 30 ENTER 719 A 40 PRINT A 50 END Comment Special Function 342 Some HP 8642A instruments will display an Option A02 or 003 These codes are for the internal firmware and are not options that can be ordered rev 13FEB90 3 208 1 Model 8642A BR 10 MHz OUT 3 3 10 MHz OVEN OUT 33 A Abbreviations in the display 3 207 AC see EXT AC 3 207 Active function 3 199 AM PULSE INPUT 3 99 Amplitude sweep 3 83 Display resolution limits in MANUA
45. 18 RF POWER 31 62E 03 RF POWER 7 762E 03 RF POWER 2 510E 03 RF POWER 794 3E 06 RF POWER 79 43E 06 RF POWER 7 943E 06 50 12E 03 12 30E 03 3 981E 03 1 259E 03 125 9E 06 12 59E 06 RF POWER 31 62E 03 50 12E 03 TUNED RF 794 3E 06 1 259E 03 1 HP 8642B only 2 HP 8642A only 4 52 rev 08J UL88 Model 8642A B Performance Test Record Performance Test 2 Harmonic Tests Harmonic Sub Harmonic Test HP 8642 HP 8642 Harmonic Results Watts AMPTD FREQ Sub Harmonic 1 000000 25 12E 06 1 500000 25 12E 06 166 666667 25 12E 06 250 000000 25 12E 06 2000 000000 316 2E 09 500 000000 5 25 12E 06 333 333333 1 25 12E 06 Performance Test 3 Pulse On Off Ratio Test Frequency 1300 0 1 wa 100 00 E 12W 1 8642B only RF Performance Test 4 Residuals Tests Resisdual AM HP 8642 1 MHz 0 010 HP 8642 AMPTD dBm 1 GHz 0 010 1 3 GHz 0 010 1 MHz 0 010 1 GHz 0 010 1 3 GHz 0 010 1 HP 8642B only rev 08JUL88 4 53 Performance Test Record Model 8642A B Performance Test 4 Residuals Tests cont d Residual FM Resuits kHz HP 8642 s 250 MHz 0 5 GHz 1 GHz 1 3 GHz Performance Test 5 AM FM and PM Tests AM Indicator Accuracy FREQ 90 90 90 90 1 HP 8642A only 2 HP 8642B only Incidental PM Results 0 20 rad 0 20 rad 1 HP 8642A 2 HP 8642B HP 8642 FREQ M
46. 3 77 How to Set the Current Output Amplitude Setting to Be the Amplitude Reference 3 77 REF SET W324 Say cde ae EUER CE wak axa 3 78 How to Set a Reference to a Specific Amplitude in units of dBm V mV EMF V EMF mV EMF aV 3 78 REF SET T lo e LRL oot 3 79 How to Set a Reference to a Specific Amplitude in units of dB relative for example dBf or dBV oe eo ite fa E VORHER 3 79 How to Reference to the Signal Generator s Last Selected Reference 3 80 How to Display the Current Reference 3 80 REL OFF ass tan sies 3 81 How to Turn Off the Relative Mode 3 81 HP IB Codes cer RED rs 3 81 Comments au s Res 3 81 AMPLITUDE SWEEP 3 83 Table 3 16 Amplitude Sweep Operating Characteristics 3 83 How to Turn On Amplitude Sweep 3 83 START AMPTD STOP AMPTD 3 84 How to Set Start and Stop Amplitude Values 3 84 How to Stop the Sweep 3 84 AUTO MANUAL SINGLE 3 84 How to Select a Sweep Mode 3 84 TIME I Ress eese aan G 3 85 How to Set Sweep Time 3 85 How to Set Sweep Time Using Sweep Time to Set Amplitude Step Size and Number of Steps esses Eh es at Wake A End 3 86 HP IB Codes reser Ree 3 92 Comments n 8 92
47. 49 RF OFF ON 3 72 RF output see amplitude 3 69 RMT 3 207 RQS see SRQ 3 200 RQS MASK 3 27 3 34 s Save registers 3 161 SAVE 3 15 Save recall 3 157 SC abbreviation 3 208 Self calibration 3 8 Self test 3 8 Self diagnostics 3 1 SEQ 3 161 Sequence dependency 3 12 Exceptions to flowcharts 3 14 Flowcharts of 3 13 Function list 3 13 How to avoid 3 12 Sequence 3 161 Service messages 3 179 3 211 Index SET SEQ 3 161 Shift key functions 3 35 SINGLE sweep mode Amplitude 3 84 Frequency 3 51 SPCL 3 168 Special functions 3 35 3 167 0 SPCLS 4 9 OFF 3 172 03 SERVICE MODE SEE MANUAL 3 172 3 201 04 ALC OFF 3 74 05 EXT LOW RATE FM ON 3 112 06 FM PRE EMPHASIS ON 3 113 07 LOW DISTORTION ON 3 115 3 124 08 PREFER HETERODYNE BAND 3 41 09 ATTEN RANGE HOLD ON 3 74 100 ALL SPCLS 200 OFF 3 172 111 SPCL FUNC VERIFY OFF 3 172 112 INT EXT LOW RATE FM ON 3 112 113 MOD FRQ CORRECTION OFF 3 133 114 NEGATIVE M POLARITY 3 124 115 NEGATIVE FM POLARITY 3 115 116 DCFM CORRECTION OFF 3 116 117 DCFM UPDATE MODE ON 3 116 118 AC COUPLED DCFM ON 3 116 119 DISABLE SETTLING 3 173 121 S WEEP UP AND DOWN 3 66 3 93 122 LINEAR AMPTD SWEEP 3 94 123 PHASE CONTINUOUS SWEEP 3 49 134 TURN OFF LCD LIGHTING 3 174 135 DISABLE DISPLAY 3 174 240 DECR FREQ 0 1 HZ 3 42 241 INCR FREQ 0 1 HZ 3 42 242 PHASE DECR 1 DEGREE 3 42 243 PHASE INCR 1 DEGREE 3 42 244 PHASE DECR 5 DEGRE
48. Are Accepted If the amplitude values entered are accepted both values will appear 1n the display If the amplitude values entered are not accepted a message will either be queued up or displayed to direct you to the entry error Modulation Types Not Possible During Amplitude Sweep AM and pulse modulation are not possible during amplitude sweep Limitations on Display Resolution When Manually Sweeping in Volts Units During manual sweep when the end points are set in volts it may seem like the Signal Generator is not reaching the selected end points Also when Linear Amplitude Sweep Special Function 122 is selected with a sweep set in volts the display may seem to change more coarsely than the actual output is changing The display operates in these ways because the displayed value is always rounded internally in 0 1 dB units and then converted to volts Converting Amplitude Units Refer to Amplitude Units Conversion on page 3 205 for information about changing amplitude values from one unit to another Zero Span for Amplitude Sweep To calculate the number of X axis steps automatically selected for zero span refer to calculation 1 on page 3 86 To calculate a sweep time that could be selected for a desired number of X axis steps refer to calculation 3 on page 3 87 The maximum number of X axis steps is 1023 or 1024 points Model 8642A B Operation Amplitude Sweep cont d Related Special Functions Relative Amplitude
49. IB portion of this Section III SP9 LIMITS MAX AMPTD E76 4076 Special Function 9 Attenuator Range Hold limits the maximum amplitude that can be selected To resolve this problem either 1 select Attenuator Range Hold Off Special Function 209 or 2 select an amplitude within the held amplitude range selected refer to Table 3 15 page 3 75 or Figure 3 9 page 3 76 or 3 refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section IIT AMPTD SP9 LIMIT MAX AM E77 4077 The amplitude selected with Special Function 9 Attenuator Range Hold limits the maximum value of AM that can be selected To resolve this problem either 1 select Attenuator Range Hold Off Special Function 209 or 2 reduce the amplitude setting to get the desired AM setting or 3 select an AM setting allowed with the held range and amplitude setting selected refer to Table 3 15 page 3 75 or Figure 3 9 page 3 76 or 4 refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III SP9 PREVENTS PULSE E78 4078 Pulse modulation is not possible when Special Function 9 Attenuator Range Hold is selected Select Attenuator Range Hold Off Special Function 209 before selecting pulse modulation PULSE PREVENTS SP9 E79 4079 Special Function 9 Attenuator Range Hold is not possible when pulse modulation is selected Turn off pulse modulation HP IB PLOF and set out
50. INSTR PRESET How to Set Increment Size Select a function then select NCR SET the desired increment set value and appropriate units key How to Increment a Function Select the desired function key Each time you press a Step key the function s value changes by one step The Step keys repeat when held down If no increment set value has been selected the Step keys use the default increment set value to change the value of the active function 3 149 Operation Model 8642 Step Increment Set How to Display the Increment Value HP IB Codes Comments 3 150 To display the function s increment size select the active function s key then SET Example Set a 10 MHz increment set value for RF frequency Then decrement the 100 MHz RF frequency by 30 MHz ENTRY CU Co C x program FRIS 10 MZ FRDN FRDN FRDN codes Display ng Am 7 rara rim i KI kI kI Z YH un The increment value is displayed as it is entered After the increment set value is entered the display returns to show the current instrument state Note the change in frequency value as the step key is pressed The digit the cursor is pointing to does not change its value as the Step key is selected Refer to Knob page 3 141 for information about other ways to change values using the cursor positioning keys INCR SET Step Down Step Up Function should be preceded by an active functi
51. Knob Resolution Could Be Useful Via HP IB Knob Increment Knob Hold and moving the cursor with the cursor positioning keys can be programmed via HP IB The programmability of these functions could be useful for example when preparing a setup before setting the instrument to local Physical Knob rotation must be performed from the front panel The Meaning of Multiple Cursors The Knob Hold function and the Knob Increment function can both be useful but initially might cause some confusion by displaying so many cursors Knob Hold could cause you to have as many as three cursors in the display at once The following summary 1s listed by quantity of cursors in the display One cursor in the display 1 One cursor over a digit 3 ww 7 rA i dv I L 5558060000 Indicates normal active function status Also indicates the least significant digit that will change as you turn the Knob 3 145 Operation Knob cont d 3 146 2 gt Mode 8642A B One cursor above the first letter of the units specifier r Rm SMP Indicates that the function 1s the active function and Knob Hold is selected on some other function that is not currently displayed When you use the Step keys the value of the displayed function will be stepped not the Knob held function When you turn the Knob the held function will appear in the display along with two cursors and that function s value will chan
52. MHz frequency reference First select INSTR PRESET Then perform the following steps LOCAL keys REF SET FRRS 1 MZ program codes Display b d i Th ITI duaod52 dg lgl n FREQ REL AMPTO The FREQ REL annunciators indicate the frequency display is relative to a reference frequency The displayed frequency is 99 MHz relative the absolute output frequency is the displayed frequency plus the frequency reference 99 MHz 1 MHz 100 MHz How to Reference to the Signal Generator s Last Selected Reference Turn on the relative frequency mode from the absolute frequency mode by setting the frequency reference to the last selected value FREQ REF SET CSHFT FREQ OFF How to Display the Current Frequency Reference FREQ J REF SET SHIFT FREQ Model 8642A B Operation Relative RF Frequency cont d REL OFF How to Turn Off the Frequency Relative Mode CFREQ REL OFF EE FREQ REFSET CSHFT FREQ OFOD HP IB Codes REF SET REL ZERO REL OFF FREQ OFF ON FRRSOF FRRSON Comments Range of Relative RF Frequency Settings Allowable settings for the frequency reference when using either the 8642A or 8642B range from 2115 to 2115 MHz When the relative frequency display is less than or equal to 2000 MHz the display is shifted to the right and the 1 Hz 0 0000001 MHz digit becomes hidden under the M of the MZ terminator Then with the cursor over
53. MSSG key If the messages encountered cannot be found in the Operating Messages operating instruction beginning on page 3 177 refer to the Service Manual The power up self check takes approximately 20 seconds Instrument Preset is selected with INSTR PRESET This function sets the Signal Generator to the initialized state described on page 3 138 Partial Preset is selected with PARTIAL CSHIET INSTR PRESET and enables you to set the instrument to a known state without losing some frequently used settings This function maintains some current instrument settings turns off others while maintaining their last selected values so they can be selected on with the COFF ON key and resets other settings to Instrument Preset values Because Partial Preset does not reset the entire instrument state it takes less time than does Instrument Preset For example Partial Preset may take only a few hundred milliseconds while Instrument Preset takes approximately two seconds How Turning the Power On Affects Instrument Settings Switching the POWER switch from STBY to ON changes the instrument settings to those listed for Instrument Preset refer to How Instrument Preset Affects Instrument Settings on the following page plus the following HP IB isset to local mode The Signal Generator is configured to an unaddressed condition The HP IB address is set to that of the internal switch if RAM memory has been lost RA
54. New A3 before down loading back up data from A20 VALID CAL 0 U619 Functional HP 8642A VALID CAL 01234 6 89 U619 Functional HP 8642B VALID CAL 0123456789 U619 3 Use the key sequence in Table 5 6 to display the cal data stats for the module s you are interested in See Interpreting Ca Data Stats later in this section Table 5 6 A3 Cal Data Stats Display Service Special Function ID Number HP 2542 Display Key Sequence for A3 0 Mode 40 Hz 0 Serial 41 Hz 0 Options 1 42 Hz 1 A11 Stats 11 Hz 2 A12 Stats 12 Hz 3 A6 Stats 13 Hz 4 A13 Stats 14 Hz 5 A19 Doubler Stats 15 Hz 2 6 A16 or A19 Attenuator Stats 16 Hz 7 A19 Rev Pwr Protect Stats 17 Hz2 8 A14 Stats 18 Hz 9 A2 Stats 19 Hz 1 Some HP 8642A instruments will display an Option A02 or 003 These codes are for the interna firmware and are not options that can be ordered 2 it these special functions are used an HP 8642A INVALID CHOICE 670 wil appear in the display rev 13FEB90 5 7 Adjustments Model 8642A B 5 8 Interpreting Cal Data Stats When viewing the HP 8642 Cal Data Stats you will see the Module ID Number refer to Table 5 4 the word STAT and three pieces of data The first field to the right of STAT is the Cal Method Number If the number is 8999 or below the Cal Data was generated at the factory If the Cal Method Number is 9000 or greater the Cal Data was generated using on
55. Note that in Stepped Frequency Sweep a faster sweep time usually results in fewer steps with a larger step size For Phase Continuous Frequency Sweep sweep span and sweep time are coupled together that is one may limit the setting of the other Also frequency will change in a phase continuous manner but the X axis output will change in steps The following pages contain detailed information about how to understand the relationships between sweep span sweep time step size and number of steps for both Stepped Frequency Sweep and Phase Continuous Frequency Sweep If you are not interested in these details you can just adjust sweep time until the approximate desired number of steps or step size is obtained To skip these sweep time details turn to page 3 64 The remaining portion of How to Set Sweep Time is comprised of two parts The first part which starts on page 3 53 develops some calculations for Stepped Frequency Sweep that will enable you to determine 1 the number of steps automatically selected 2 the frequency step size automatically selected 3 the required sweep time that will select a desired number of frequency steps and 4 the required sweep time that will select a desired step size The second part which starts on page 3 60 develops some calculations for Phase Continuous Frequency Sweep that will enable you to choose frequency span and sweep time so each allows the other s settings The sweep span limits liste
56. Operating Fundamentals are abbreviated front panel operating instructions included with Volume 1 as a separate booklet which will enable you to operate the basic functions of the Signal Generator without using the more detailed and extensive portions of the Operating Manual However the Detailed Operating Instructions in Section 3 can provide more specific information which can be easily accessed with an Index rev 30SEP88 1 3 General Information Mode 8642A B 1 8 ACCESSORIES SUPPLIED WITH THE 8642A B The line power cable is the only accessory supplied with the Signal Generator The line power cable is selected at the factory according to the line power requirements specified by the customer If the line power cord type is not specified it will be selected according to the voltage available in the country of destination For the part numbers of the power cables refer to Table 2 1 on page 2 4 Power Cable and Mains Plug Part Numbers Signal Generators shipped to countries using 115 volts are also supplied with a set of fuses for 230 volt operation 1 9 OPTIONS AVAILABLE WITH THE INSTRUMENT 1 4 Electrical Options Electrical option numbers can be displayed on the front panel or read via HP IB Refer to page 3 208 1 for more information Option 001 High Stability Time Base This optional time base improves the frequency accuracy and stability of the internal reference oscillator Refer to Table 1 1 for specifications Option
57. Related Special Functions 3 93 121 Sweep Up and Down On 3 93 Figure 3 10 Sweep Waveforms 3 93 122 Linear Amplitude Sweep 3 94 3 67 Operation Model 8642A B AMPLITUDE L GENERATOR 01 2100 MHz no GERI gt kO JU Ula o s DLE Favre nef IER EE i 6 XY E PE 5 ju J a J TA VE 2 d This key makes amplitude the active function so its me m value can be set using either Data keys the Knob Step 5 keys or the Off On key The EMF mode enables you to display and enter Ce amplitude values units w C GJ OFF ON 4 key provides convenient rapid way to toggle 007007 umaman the RF Output off and on without changing the attenuators 9 ENTRY REF SET ZERO These functions enable relative amplitude settings These keys enable an amplitude sweep The sweep modes available are auto manual or single These terminator keys enable you to complete a data entry EE Cio Figure 3 8 Amplitude Related Functions Operation Description AMPLITUDE Model 8642A B Output amplitude can be entered directly in units of dBm V mV uV and dBuV EMF amplitude units can also be directly entered in units of EMF V EMF mV EMF uV and dB EMF uV The Attenuator Range Hold function Sp
58. STR Jade Gray 8120 2191 STR 90 Jade Gray 8120 4379 90 90 Jade Gray Part number shown for plug is industry identifier for plug only Number shown for cable is HP Part Number for complete cable including plug Earth Ground L Line N Neutral STR Straight 9 4 reu 07JUL87 HP IB Address Selection The Signal Generator s address is set to 19 at the factory both in RAM memory and an internal switch located inside the instrument The address stored in RAM remains valid through switch ing the power from standby to on and unplugging of the ac power cord unless the internal bat tery power is lost which would cause RAM memory to be lost If RAM memory is ever lost the address on the internal switch is read and becomes the address at turn on Refer to page 3 8 for procedures to set the Signal Generator s HP IB address Interconnections um Interconnection data for the Hewlett Packard Interface Bus is provided in Figure 2 2 Hewlett Packard Interface Bus Connections Mating Connectors Interface Connector The HP IB mating connector is shown in Figure 2 2 Note that the two securing screws are metric Coaxial Connectors Coaxial mating connectors used with the Signal Generator should be either the 50 ohm BNC male connectors or 50 ohm Type N male connectors that are compatible with those specified in US MIL C 39012 Operating Environment The operating environment should be within the following limitat
59. Signal Generators modulation frequency display refers to the internal modulation oscillator only Deviation and the desired value of FM deviation in MHz kHz or Hz per volt When using an external source the FM deviation setting does not set the actual deviation it sets the input sensitivity per volt A linear relationship exists between the FM deviation setting and the external voltage applied for voltages less than or equal to approximately 1 2 Vpk NOTE With simultaneous internal and external modulation the sum of the internal and external signals should not cause the FM deviation to exceed the limits mentioned in Figures 3 12 and 3 13 on page 3 106 If these limits are exceeded the Signal Generator could go out of lock which causes queued up Hardware Error messages Also the external FM M INPUT does not respond linearly to inputs greater than approximately 1 2 Vpk 3 109 Operation Model 8642A B Modulation FM cont d HP IB Codes Comments 3 110 Example Frequency modulate the RF output with an external 1 Vpk dc coupled source 80 kHz per volt FM deviation at a rate determined by the external source s frequency LOCAL keys 9 CIS x program FMXD FM 80 KZ codes These codes are not independent and might need to follow a specific sequence for entry Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III
60. Since this type of frequency sweep sweeps in a phase continuous manner no frequency steps are used although the X axis output still uses steps However you might want to choose frequency span and sweep time so each allows the other s settings as described on page 3 52 Also you can calculate X axis steps available at the rear panel output The information that follows will enable you to calculate 1 the minimum sweep span for a desired sweep time and frequency band page 3 61 2 the maximum sweep span for a desired sweep time and frequency band page 3 61 3 the minimum sweep time for a desired sweep span and frequency band page 3 61 4 the maximum sweep time for a desired sweep span and frequency band page 3 61 5 the number of automatically selected X axis steps based on a sweep time setting page 3 62 and 6 the required sweep time to select a specific number of X axis steps page 3 62 Since some of the calculations below use the frequency band divide number the number for each band is listed in the following table RF Frequency Range Divide Number 1057 500001 to 2115 000000 8642B only 528 750001 to 1057 500000 264 375001 to 528 750000 132 187501 to 264 375000 66 093751 to 132 187500 33 046876 to 66 093750 16 523438 to 33 046875 8 261719 to 16 523437 4 130860 to 8 261718 0 100000 to 4 130859 0 100000 to 132 187500 9 8 7 6 5 4 3 2 1 I If the frequency span is not possible from a divide
61. TUNED RF 794 3E 18 TUNED RF 158 5E 18 TUNED RF 125 9E 15 12 59E 15 1 259E 15 251 2E 18 1 On the HP 8902A Measuring Receiver press CALIBRATE before continuing test 4 5 the HP 8902A Measuring Receiver press blue SHIFT STORE followed by the numeric key indicated by the note number 8 HP 8642B only 9 HP 8642A only rev 08JUL88 Performance Test 1 4 7 Performance Tests Model 8642A B Measuring Results watts HP 8642 8642 FREQ Receiver Mensuring MHz eno Receiver RF POWER 39 81E 03 63 09E 03 RF POWER 31 62E 03 50 12E 03 RF POWER 7 762E 03 12 30E 03 RF POWER 2 510E 03 3 981E 03 TUNED RF 794 3E 06 TUNED RF 79 43E 06 TUNED RF 7 943E 06 TUNED RF 794 3E 09 TUNED RF 79 43E 09 1 259E 03 125 9E 06 12 59E 06 1 259E 06 125 9E 09 TUNED RF 7 943E 09 TUNED RF 794 3E 12 TUNED RF 79 43E 12 TUNED RF 7 943E 12 TUNED RF 794 3E 15 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 TUNED RF 79 43E 15 TUNED RF 7 943E 15 TUNED RF 794 3E 18 TUNED RF 158 5E 18 TUNED RF RF POWER 31 62E 03 50 12E 03 TUNED RF 794 3E 06 1 259E 03 125 9E 15 12 59E 15 1 259E 15 251 2E 18 TUNED RF 79 43E 06 TUNED RF 7 943E 06 TUNED RF 794 3E 09 TUNED RF 79 43E 09 125 9E 06 12 59E 06 1 259E 06 125 9E 09 TUNED RF 7 943E 09 TUNED RF 794 3E 12 TUNED RF 79 43 12 TUNED RF 7 943 12 TUNED RF 794 3E 15 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 TUNED RF 79 43E 15 TUNED RF 7 94
62. These messages describe the Signal Generator s reason for not executing an attempted setting Refer to Messages page 3 177 for more information about these messages each message code is prefixed with the letter E in that listing The presence of one of these messages is signaled when bit 2 of the Status Byte is set Refer to Status Byte on page 3 29 Some service related messages can also cause this bit to be set Refer to the Service Manual Parameters Changed Messages OC These messages inform you that the Signal Generator has changed some other setting to allow a new setting Some of the Signal Generators functions cannot occur simultaneously with other functions so the Signal Generator will automatically adjust or turn off the functions that are preventing the new setting For example AM is turned off when pulse modulation is selected the Output Parameters Changed Message is AM TURNED OFF 11 Refer to Messages page 3 177 for more information about these messages each message code is prefixed with the letter C in that listing The presence of this message is signaled when bit 7 of the Status Byte is set Refer to Status Byte on page 3 29 Some service related messages can also cause this bit to be set Refer to the Service Manual Examples The Signal Generator can output either the message code number or the message string the alphanumeric display for any of the above messages Table 3 6 Error Code and Messag
63. Turn off amplitude sweep HP IB AAOF ABOF before selecting the output amplitude AMPTD SWP PREVENTS AM E70 4070 AM is not possible during an amplitude sweep Turn off amplitude sweep HP IB AAOF ABOF before selecting AM AP SWP PREVENTS AP OFF E71 4071 Output amplitude cannot be turned off during amplitude sweep Turn off the amplitude sweep HP IB AAOF ABOF before turning off the output amplitude AP SWP PREVENTS PULSE E72 4072 Pulse modulation is not possible during an amplitude sweep Turn off the amplitude sweep HP IB AAOF ABOF before selecting pulse modulation AP SWP PREVENTS SP4 E73 4073 Special Function 4 ALC OFF is not possible during amplitude sweep Turn off amplitude sweep HP IB AAOF ABOF before selecting ALC OFF HP IB SP4 SP4 PREVENTS AP SWP E74 4074 Amplitude sweep is not possible when Special Function 4 ALC OFF is selected Select Disable ALC OFF Special Function 204 before selecting amplitude sweep SP9 LIMITS MIN AMPTD E75 4075 Special Function 9 Attenuator Range Hold limits the minimum amplitude that can be selected To resolve this problem either 1 select Attenuator Range Hold Off Special Function 209 or 2 select an amplitude within the held amplitude range selected refer to Table 3 15 page 3 75 or Figure 3 9 page 3 76 or 3 190 rev 20MAR85 Model 8642A B Operation Operating Messages cont d 3 refer to the Sequence Dependency discussion that begins on page 3 12 in the HP
64. Turn on Special Function 9 Attenuator Range Hold On x program codes Display H RA SPCL Attenuator Range Hold has been selected Note the display of the SPCL annunciator Press the SHIFT key twice to return the display to the current instrument state if desired You Can Disable the Automatic Special Description Display The description that occurs each time a special function is selected can be disabled using Special Function 111 Disable the Automatic Special Function Verification Display 3 168 Model 8642A B Operation Special Functions cont d SPCL 2XX How to Turn Off Special Functions Special functions can be turned off using the following procedures Turn off a single special function For example Special Function 209 Attenuator Range Hold Off will turn off Special Function 9 Attenuator Range Hold On Each special function that has a numeric code less than 200 can be disabled using a special function code that is comprised of the number 200 added to the last 2 digits of the special function or added to the single digit for single digit special functions For example Special Function 4 is disabled with Special Function 204 Special Function 112 1s disabled with Special Function 212 etc 9 Select Special Function 0 Special Functions 4 through 9 Off to turn off Special Functions 4 through 9 This is convenient when frequently using just one single digit special function
65. Zero function was selected After setting the amplitude reference the dBm key operates as a dB terminator note the dB printed above the dBm key For example after setting the output to read in dB relative units just key in 20 dB to output 20 dB relative to the absolute amplitude when the Relative Zero function was selected How to Set a Reference to a Specific Amplitude In units of dBm V mV uV EMF V EMF mV EMF uv 3 78 Setting a specific PF amplitude as the amplitude reference causes subsequent amplitude settings to display the current output amplitude as dB relative to the amplitude reference CAMPTD REF SET SHET AMPTD followed by the value of the desired reference amplitude in dBm V mV or uV REF SET Example 1 Configure the front panel to allow all amplitude setting values to be entered and displayed as offset from a 1V amplitude reference First select INSTR PRESET to put the instrument in a known state then ENTRY LOCAL keys APRS 1 VL program codes Disp ay The AMPTD REL annunciators indicate the displayed amplitude is relative to a reference amplitude The displayed amplitude is 153 0 dB the actual output amplitude is the displayed amplitude plus the amplitude reference To convert the amplitude reference to dBm first exit the relative mode then select your reference amplitude as the absolute output amplitude 1V in this case then press the dBm key The equiva
66. a sub set of the full Performance Tests in this section rev 08J UL88 4 1 Performance Tests Model 8642A B Self Test At power up the HP 8642 internal controller executes a 20 second operational check which is termed Self Test The Self Test quickly evaluates the correctness of operation and provides the operator with a 9096 assurance that the HP 8642 is fully operational There is also an instrument level self test that evaluates the correctness of operation and provides the operator with an 8096 assurance that the HP 8642 is operating within its specifications Refer to the INSTRUMENT LEVEL SELF TEST under the DIAGNOSTIC tab in Section 8 Post Repair Performance Testing When the HP 8642 Module Exchange philosophy of repair is utilized by the customer Performance Testing is not required Exchange modules are tested to levels of performance specified to insure HP 8642 warranted performance and calibration Refer to the diagnostics tab in Section 8 for Module Replacement procedures 4 2 rev 08JUL88 Model 8642A B Performance Tests Performance Test 1 LEVEL ACCURACY AND FLATNESS TESTS Specification Electrical Characteristics Performance Limits OUTPUT Level 8642B 20 dBm to 140 dBm band 1 7 19 dBm to 140 dBm band 8 18 dBm to 140 dBm band HET 17 dBm to 140 dBm band 9 16 dBm to 140 dBm band 10 Level 8642A 20 dBm to 140 dBm band 1 7 18 dBm to 140 dBm band 8 HET 16 dBm to 140 dBm ba
67. and Calibration Manual SERIAL NUMBERS This manual applies directly to instruments with serial numbers prefixed 2427A to 2930A and all major changes that apply to your instrument modules For additional important information about serial numbers refer to INSTRUMENTS COVERED BY THIS MANUAL in Section 1 Third Edition This material may be reproduced by or for the U S Government pursuant to the Copyright License un der the clause at DFARS 52 277 7013 APR 1988 Copyright HEWLETT PACKARD COMPANY 1989 EAST 24001 MISSION AVENUE TAF C 34 SPOKANE WASHINGTON U S A 99220 Operation and Calibration Manual HP Part 08642 90224 Other Documents Available Microfiche Operation and Calibration Manual HP Part 08642 90225 Service Manual Volume 1 2 3 HP Part 08642 90226 Microfiche Service Manual HP Part 08642 90227 Printed in U S A March 1996 Model 8642A B Safety Considerations SAFETY CONSIDERATIONS GENERAL This product and related documentation must be re viewed for familiarization with safety markings and instructions before operation This product is a Safety Class I instrument provided with a protective earth terminal BEFORE APPLYING POWER Verify that the product is set to match the available line voltage and the correct fuse is installed SAFETY EARTH GROUND An uninterruptible safety earth ground must be pro vided from the main power source to the product input wi
68. band but would be possible if the Het band was used the Signal Generator will automatically select the Het band 1f Special Function 8 Prefer Heterodyne Band is not selected However if the divide band or the Het band could be used the Signal Generator will select the divide band For example if a sweep setting of 120 0 to 120 4 MEz is selected the Signal Generator will automatically select the heterodyne band because a 400 kHz span is not possible 1n Band 6 But if a sweep setting of 120 00 to 120 03 MHz is selected the Signal Generator will automatically select band 6 Refer to RF Frequency page 3 39 for more information about the divide bands and the heterodyne band Model 8642A B Operation RF Frequency Sweep cont d 1 Calculate the minimum possible non zero frequency sweep span for a desired sweep time setting Minimum non zero frequency sweep span in Hz equals the maximum of 1 Hz or 0 2 Hz per second x Divide Number Sweep Time n s If the result is not an integer use the next highest integer for example if the result is 5 78 Hz use 6 Hz if the result is 5 0 Hz use 5 Hz 2 Calculate the maximum frequency sweep span for a desired sweep time setting Maximum frequency span in Hz equals the minimum of 400 000 Hz Divide Number or 500 kHz per second INTEGER oF Divide Number X Sweep Time in ms 3 Calculate the minimum fastest sweep time setting for a desired non zero frequ
69. ber is 08642 80058 Note that if metric hardware is used the rear panel of the instrument mentions that fact 2 4 STORAGE AND SHIPMENT Environment The instrument should be stored in a clean dry environment The following environmental limitations apply to both storage and shipment Temperature 55 C to 75 Humidity 5 to 95 maximum wet bulb temperature 40 C Altitude 15 300 meters 50 000 feet Packaging Original Packaging Containers and materials identical to those used in factory packaging are available through Hewlett Packard offices If the instrument is being returned to Hewlett Packard for servicing attach a tag indicating the type of service required return address model number and full serial number Also mark the container FRAGILE to assure careful handling In any correspondence refer to the instrument by model number and full serial number Other Packaging The following general instructions should be used for repackaging with com mercially available materials 1 Wrap the instrument in heavy paper or plastic If shipping to a Hewlett Packard office or service center attach a tag indicating the service required return address model number and full serial number 2 Use a strong shipping container double wall carton made of 2 4 MPa 350 psi test material 1s adequate 3 Use enough shock absorbing material 75 to 100 mm layer 3 to 4 in around all sides of the instrument to provide firm cush
70. combinations of the two sources How to Set with the Internal Source Using the Modulation Oscillator 3 120 Source CSHET Rate MOD FREQ and the desired value of modulation frequency in KHz or Hz Deviation CSHIFT and the desired value of deviation in radians RAD 96 Model 8642A B Operation Modulation cont d Example Phase modulate the RF output using the internal modulation oscillator at a 10 kHz rate with 12 radians deviation MODULATION SOURCE program PMNT MF 10 KZ PM 12 RD codes These codes are not independent and might need to follow a specific sequence for entry Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III Display The RF output is being internally phase modulated as indicated by the and INT annunciators deviation is 12 0 radians Modulation frequency is set to 10 00 kHz The cursor above the setting indicates that 15 the active function EXT AC EXT DC How to Set M with an External Source Source Do not apply more than 15 Vpk maximum external voltage to the INPUT damage to the Signal Generator s circuitry could result The external modulation source connects to the INPUT connector input impedance of 600 ohms The external modulation signal level should be adjusted to a 1 Vpk 0 707 Vr
71. consumption is 260 VA maximum 270 VA during attenuator switching Installation WARNING This is a Safety Class I product ie provided with a protective earth terminal An uninterruptible safety earth ground must be provided from the Mains power source to the product input wiring terminals power cord or supplied power cord set Whenever it is likely that the protection has been impaired the instrument must be made inoperative and be secured against any unintended operation lf this instrument is to be energized via an external autotransformer for voltage reduction make sure that the common terminal is connected to the earthed pole of the power source CAUTION BEFORE PLUGGING THIS INSTRUMENT into the Mains line voltage be sure the correct voltage and fuse have been selected Model 8642A B A rear panel line power module permits operation from 100 120 220 or 240 Vac The number visible in the window located on the module indicates the nominal line voltage to which the instrument must be connected Verify that the line voltage selection card and the fuse are matched to the power source Refer to Figure 2 1 Line Voltage and Fuse Selection Two fuses are supplied with each instrument One fuse has the proper rating for 110 120 Vac line operation HP part number 2110 0003 3A 250V non time delay The other fuse is rated for 200 220 Vac operation HP part number 2110 0002 2 250V non time delay One fuse is instal
72. control on a function even if it is no longer the active function With Knob Hold the Step keys and Data keys enable control of the new active function while allowing the Knob to continue control of the held function While Knob Increment is selected the Knob is less sensitive to the Knob rotation rate in affecting how much a setting is changed as the Knob is turned This gives you the capability to make individual precise steps with more control using the Knob The Signal Generator powers up with the Knob function enabled with RF frequency as the active function Therefore unless the Knob is disabled for example by selecting ENTRY OFF RE OFF ON any rotation of the Knob changes the value of the active function Note Put the instrument in its initialized state by selecting INSTR PRESET How to Control Knob Resolution Using the Cursor Positioning Keys The cursor position specifies the Knob resolution unless Knob Increment is selected For example a cursor above the 2 in a 260 HZ FM display indicates that the Knob will change the FM value in 100 Hz steps You can re position the cursor with the and keys to change Knob resolution by a factor of ten 3 141 Operation Model 8642A B Knob cont d Example o Controlling Knob Resolution Using the Cursor Positioning Keys RF frequency is set to 100 MHz Set the Knob to step this value in 1 kHz steps First set the RF Frequency to 100 MHz then lt gt
73. current status of the instrument the Status Byte should be read again Note that the act of reading the Status Byte alone does not clear any status bits If the instrument does not have an unresolved hardware error the Status Byte will be cleared by executing any of the following Sending Clear Status CS Sending Instrument Preset IP Sending Device Clear or Selected Device Clear Switching the Power from Standby to On You can also clear the Status Byte by clearing the individual status bits Refer to Table 3 7 on the following page NOTE Bits 3 Local Remote and 4 Ready are not affected by clearing the Status Byte They always output their actual values Operation x Status Byte cont d END OF SWEEP HARDWARE ERROR EXECUTION ERROR LOCAL REMOTE ERROR RQS IEEE 488 PARAMETER CHANGED Model 8642A B Table 3 7 HP IB Status Byte Bit Definitions HP IB Operating Condition Single sweep finished Instrument out of lock reverse power tripped or instrument firmware malfunction Syntax or function execution error instrument in local operation Typically always set Logical OR of bits 1 and 2 RQS mask is ANDed with the Status Byte and the result is not equal to 0 refer to Service Request for more information Previous setting has been automatically changed for example FM is turned off when becomes active Reset with auto manual or a new single sweep
74. earnest e n Deis net eee or ai SRL af OA TR HP 8902A Sensor ele lle PEE eee per V Rae ei s oido ee woe cuales HP 11722A rev 08J UL88 Performance Test 2 4 9 Performance Tests Model 8642A B Procedure Setup 1 Connect the instruments as shown in Figure 4 2 2 Preset the instruments 3 Set the measuring receiver to tuned RF Level mode If the Level Accuracy Performance Test Performance Test 1 has just been done with the same measuring receiver calibration is not required If the Level Accuracy Performance Test Performance Test 1 has not yet been done or you have changed measuring receivers then calibration is required Complete the following calibration procedure before continuing Calibration 4 Perform the Level Accuracy Performance Test Performance Test 1 at the following frequencies 3 10 100 500 1000 and 1300 MHz for HP 8642B and levels 0 40 80 dBm If the measuring receiver is an HP 8902 store calibration values when instructed by footnotes 2 7 in Performance Test 1 tables Harmonics Sub Harmonic 1 Set the HP 8642 amplitude and frequency to the values in the following table 2 Set the measuring receiver to the frequencies in the Harmonic Sub Harmonic MHz column and record the results in the Actual column 3 Verify that the level is below the specified minimum HP 8642 HP 8642 Harmonic AMPTD FREQ Sub Harmonic dBm MHz MHz EE 1 000000 3 0 2 25 12E 06 1 500000 3 002
75. found in a standard tool box necessary to service the HP 8642A B Order the HP 11801A to service the HP 8642A Order the HP 11801B to service the HP 8642B Order the HP 11801C to service both instruments Refer to Table 1 5 on page 1 17 for a complete parts listing of the On Site Service Kit Although two part numbers are listed for modules in the On Site Service Kit only the new or the restored module will be included in the kit Bench Service Kit This kit in conjunction with the HP 8642A B Service Manual is directed at component level repair and module calibration of the HP 8642A B The kit contains special tools and troubleshooting aids such as a Torx torque wrench and Torx bits test adapters and special cables and cable adapters etc Order the Bench Service Kit as HP part number 11802A Refer to Figure 1 2 on page 1 19 for a complete parts listing of the Bench Service Kit Signal Generator Test System HP 8902SG including HP 11808A software This test system provides the necessary equipment for automated performance testing of the HP 8642A B 50 Ohm to 75 Ohm Adapter This adapter is an impedance matching network required for testing with 75 ohm cabling and or loads Order the adapter with HP part number 11687A Fiberglass Transit Case Order this protective case for shipping and transporting the HP 8642A B Signal Generator as HP part number 9211 2661 Rack Slide Kit This heavy duty rack slide kit is the kit recommended
76. frequency display so it indicates the change with a lighted MSSG annunciator Scrolling through the message list using the MSSG key will then display the amount of frequency change in the form RF FREQ DISPLAY 0 2 HZ 142 This message means that the actual output frequency is the displayed value minus 0 2 Hz These 0 1 Hz Special Functions are disabled when you set a new frequency value 242 Phase Decrement 1 Degree 243 Phase Increment 1 Degree 244 Phase Decrement 5 Degrees 245 Phase Increment 5 Degrees These functions change the RF signal s output phase by the indicated amount each time the special function is selected For example selecting SPCL CSHFT gt 4 C4 decrements output phase by 5 degrees The execution of this particular special function is indicated by the special function verification display which reads 244 PHASE DECR 5 DEGREES 250 Phase Adjustment from Knob and Step Up and Step Down Keys This function enables control over the RF signal s output phase in one degree steps using either the Knob or the Step keys Model 8642A B Operation RF Frequency cont d Related Operating Instructions Refer to Relative RF Frequency page 3 45 for information on designating a particular frequency as a reference frequency and on displaying all subsequent RF frequencies as offsets from that reference Refer to RF Frequency Sweep page 3 49 for information on selecting a frequency sweep Refer to
77. identical ANSI Standard 1 is described at the bottom of Table 3 1 and on page 1 2 under HP IB Capabilities HP IB Capabilities In remote mode all front panel controls are disabled except the Power switch and the Local key the Local key can be disabled by configuring the instrument in Local Lockout The Signal Generator will respond to each HP IB message below according to its associated listen or talk address Each of these capabilities is described in more detail on the pages that follow Input Data When addressed to listen with REN true the Signal Generator stops talking and can respond to input data Refer to page 3 11 Output Data When addressed to talk the Signal Generator stops listening and can send output data Refer to page 3 15 Clear Selected Device Clear SDC When addressed to listen with REN true the Signal Generator stops talking and responds to SDC by clearing any uncompleted entries or messages Refer to page 3 24 Clear Device Clear DCL Regardless of the addressed state of the Signal Generator whether addressed to listen or to talk it stops talking and responds to DCL by clearing any uncompleted entries or messages Refer to page 3 24 Local When addressed to listen with REN true the Signal Generator stops talking and responds to the Local command by returning from remote control to local control Refer to page 3 25 Local Lockout Regardless of the addressed stat gt f the Sig
78. in to display the Module ID numbers corresponding to Valid Cal Data in the A20 Switch the HP 8642 to Standby Key in to enter service mode Board The A20 board can be thought of as having 10 memory locations The address of each location numbered 0 through 9 is the Module ID Number Each memory location will either contain Valid Cal Data or it will be blank The A20 addresses that contain Valid Cal Data will now be displayed Some examples of the HP 8642 display are shown below Refer to Table 5 4 to cross reference the A20 addresses Module ID Numbers to the Memory Contents A20 containing HP 8642A Cal Data Backup A20 containing HP 8642B Cal Data Backup A20 provided with A19 exchange module A20 provided with A6 exchange module A20 containing no data Table 5 4 Module ID Numbers 1D Number Memory Contents Model Serial Options A11 Cal Data A12 Cal Data AG Cal Data A13 Cal Data A19 Doubler Cal Data A16 or A19 Attenuator Cal Data A19 Rev Pwr Protect Cal Data A14 Cal Data A2 Cal Data Q Q N O n a newly initialized A20 board there will be data stored in location 0 The data will be Model HP 864 Serial and no options Adjustments Model 8642A B 6 Use the Service Special Functions in Tabie 5 5 to display the information referred to as Cal Data Stats for the Module ID Numbers that were displayed in step 5 See Interpreting
79. in the example below to write a brief message to the display Note that if you accidentally select another key and exit the service mode you will need to re select Special Function 3 SPCL SHET 2 in order to continue entering the message CSHIFT C3 CS CHZ UV C8 C7 C3 HZ UV C8 Z S HZ UV 8 C8 C HZ UV 8 C8 C8 HZ UV C8 C3 C2 CUZ UV C8 CZ C2 HZ UV C8 C8 Co HZ UV C4 HZ UV SPCL BBEBBEBBEB BgEBBBBEEBS 3 201 Appendix B Model 8642A B Appendix B Writing Messages to the Display cont d The following display results from entering the keys from the example on page 3 201 T II ITLUYV HP Example of Entering a User Defined Message Via HP IB You can use the following example BASIC program to enter a message string of 49 characters into Message 1 Note that the terminator for each service special function is EN when in the service special function mode this is the programming equivalent of the local function of pressing the Hz key locally 10 DIM C 49 DIMENSION 49 CHARACTER STRING 20 30 INPUT C 1 INPUT CHARACTER STRING FOR MESSAGE 1 40 50 OUTPUT 719 SP3655bEN CLEAR MESSAGE 1 IN THE 8642A B 60 70 LET L LEN C DETERMINE LENGTH OF MESSAGE 1 80 90 100 FORI 1TOL CONVERT EACH CHARACTER IN C TO 110 LET A NUM ITS EQUIVALENT ASCII NUMERIC 120 OUTPUT 719 USING 130 CODE 130 IMAGE SP3656 K EN
80. is similar to the instrument serial number but appears on the modules The A2 Module Cal ID number can be found on the ribbon cable connector at the left hand side of the A2 board you will see a label with a number similar to 2412A 31458 So you would enter 4 for the Module Cal ID number 13 Now the printer should respond by printing out the statistics of the module See Figure 5 1 All the information on the print out has been discussed previously except the Calibration Method number which will be discussed in Interpreting Cal Data Stats later in this section MODULATION SECTION A2 SELF CALIBRATION CALIBRATION DATE MDY 12 25 86 INSTR MODEL HP 8642B INSTR SERIAL 2427A00209 INSTALLED OPTIONS 001 MODULE ID NUMBER 9 MODULE CALIBRATION ID 31458 CALIBRATION METHOD 9995 Figure 5 1 Typical Module Stats printout from HP 8642 Auto A djust Rountine 14 The remaining steps will be unique to each Module given in Section 8 Turn to the Section 8 Module Tab you are interested in You will find the complete Auto Adjust Procedure in the Troubleshooting and Adjustments information The procedure in Section 8 will include the above less the detailed explanation Model 8642A B Adjustments 5 3 CORRECTION DATA SPECIAL FUNCTIONS Identifying the Contents of the A20 The following is a procedure to display and identify the contents of the A20 Board 1 2 Plug the A20 on to A3J3 3 Switch the HP 8642 ON 4 5 Key
81. kHz 15 80 kHz 100 0 kHz Output Impedance 47 78 oss 52 77 Performance Test 8 SWR Tests High Level SWR Frequency MHz 4 000 4 000 4 000 4 000 1000 000 1000 000 1000 000 1000 000 2000 000 2000 000 2000 000 2000 000 4 58 reu 08J UL88 Model 8642A B Performance Test Record Performance Test 8 SWR Tests cont d Low Level SWR Reflection Signal Results Generator Return Loss Frequency MHz 4 000 4 000 1000 000 1000 000 1300 000 1300 000 Performance Test 9 Spurious Test rev 08JUL88 Spectrum Analyzer Results dBm CENTER FREQ Ref Level dBm MHz 4 130 000 85 870 000 4 130 000 3 700 000 4 130 000 0 430 000 4 130 000 4 560 000 4 130 000 5 870 000 4 130 000 4 130 000 45 000 000 225 000 000 90 000 000 600 000 000 600 000 000 571 144 000 610 519 000 745 951 000 775 184 000 780 184 000 797 878 000 965 416 000 1012 000 000 976 000 000 562 000 000 1057 500 000 1057 500 000 563 000 000 112 500 000 596 313 600 599 078 400 572 796 000 612 171 000 747 608 000 776 836 000 781 840 000 799 536 000 967 076 000 788 000 000 742 500 000 606 500 000 1012 500 000 1057 375 000 540 500 000 4 59 Performance Test Record Model 8642A B Performance Test 10 Third Order Intermodulation Signal Generator Frequency Frequenc
82. modulation oscillator an external source or combinations of the two sources INT How to Set FM with the Internal Source Using the Modulation Oscillator Source CNT Rate and the desired value of modulation frequency in kHz or Hz Deviation CFM and the desired value of FM deviation in MHz kHz or Hz Example Frequency modulate the RF output using the internal modulation oscillator at a 12 kHz rate with 80 kHz FM deviation LOCAL keys program FMNT MF 12 KZ FM 80 KZ codes These codes are not independent and might need to follow a specific sequence for entry Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section Display MOUFR 88K2 FM INT AMPTD The RF output is being internally frequency modulated as indicated by the FM and INT annunciators FM deviation is 80 0 kHz Modulation frequency is set to 12 00 kHz The cursor above the FM setting indicates that FM is the active function 3 107 Operation Model 8642 Modulation FM cont d How to Set FM with an External Source 3 108 EXT AC EXT DC Source Do not apply more than 15 Vpk maximum external voltage to the INPUT or damage to the Signal Generator s circuitry could result The external modulation source connects to the INPUT connector input impedance of 600 ohms The external modulation signal level
83. normal display of instrument settings For example let s say that you are not currently viewing the copied message list and the MSSG annunciator is being displayed due to the transient message RECALL ERROR FOUND H10 being queued up for display because sometime in the past you recalled an undefined register To view that message you need to copy the current list into the copied list So you press the MSSG key which deletes the transient message from the current message list and read all the messages The message you were being signaled to read was a transient message so when you press MSSG once more after seeing the END OF MESSAGE 00 message which brings back the normal display of instrument settings the MSSG annunciator is no longer displayed If for some reason you want to re read that message you can read the previously copied list by selecting SHET MSSG If you select MSSG J alone you will lose that message and copy the current message list into the new copied list The following messages indicate that no messages are queued up or the end of the message list has been reached To HP IB users the following messages indicate that whenever you read back a O as a message code number you know you are finished reading the copied message list Model 8642A B Operation Operating Messages cont d NO MESSAGES 00 0 No messages are queued up to be displayed or output over HP IB This message is viewed by selecting HP
84. normally only occurs during instrument power up This function can be used for example to recalibrate the modulation oscillator frequency bands if normal modulation frequency correction has been disabled with Special Function 113 Calibration typically takes one to two seconds 3 133 Operation Model 8642 A B Modulation Oscillator cont d Related Operating Instructions Refer to Modulation AM page 3 97 Modulation FM page 3 105 Modulation page 3 119 or Modulation Pulse page 3 127 for specific modulation information as well as Internal and external source information Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed 3 134 Mode 8642A B SETTING MODIFICATIONS CONTENTS Figure 3 16 Functions Relating to Modifying Settings aca deter e odes e 3 136 INSTRUMENT PRESET PARTIAL PRESET 3 137 POWER rS ose e dee enun 3 137 How Turning the Power On Affects Instrument Settings 3 137 INSTR PRESET 3 188 How Instrument Preset Affects Instrument Settings uy vss es eas ca eee ees 3 138 Table 3 25 Instrument Preset Configuration 3 138 PARTIAL 225i 22 u eU Ur ERO e 3 139
85. operating site Repair times may be longer for individuals with no prior training or experience on the HP 8642A B The following service features have been designed into the HP 8642A B Hardware Features Each major circuit function is physically located in a separate module RF modules are arranged physically from left to right in the order of their functional sequence Most intermodule connections are accessible from the top of the instrument There are no RF feedback paths between modules a feed forward design Printed on the inside top cover of the instrument is an illustrated top view of the inside of the instrument as well as a table of cable connections Built In Test Features e voltmeter and a power meter are built into the instrument e Unique service tools are stored inside the HP 8642A B cabinet Firmware Features e RF modules are connected to a diagnostic bus which allows the controller to monitor critical operating test points within the module e Critical message information concerning the operating condition of the HP 8642A B is displayed in numeric code on the front panel or can be printed via an HP IB printer without the need of an external controller e Four instrument diagnostic levels help to analyze the instrument s condition Power Up Self Check Fault Detection Self Check Instrument Level Diagnostics and Module Level Diagnostics 1 7 HOW THE OPERATING FUNDAMENTALS CAN HELP YOU LEARN TO OPERATE The
86. pV dBuV EMF V EMF mV EMF 4V dB EMF pV REL ZERO or REF SET can be used to obtain settings such as dbV or dBf Two signal generators with frequencies spaced 25 kHz apart into a resistive combiner Absolute output accuracy consists of allowances tor detector linearity temperature flatness and attenuator accuracy 1 8 rev 18MAR9I Model 8642A B General Information Table 1 1 Specifications part of 3 of 6 Electrical Characteristics Performance Limits Coin AMPLITUDE MODULATION Depth 096 to 99 996 Output level lt 10 dBm Resolution 0 1 Indicator Accuracy 3 5 of setting 1 AM 8642A Bands 1 8 HET 1 kHz rate up to 90 AM 8642B Bands 1 9 HET 5 of setting 1 AM 8642A Band 9 8642B Band 10 AM Distortion at 1 kHz Rate 8642A Bands 1 8 HET 8642B Bands 1 9 lt 1 0 to 30 AM lt 2 30 to 70 AM lt 4 70 to 90 AM 8642A Band 9 HET 8642B Band 10 HET lt 2 0 to 30 AM lt 4 30 to 70 AM lt 6 70 to 90 AM AM 3 dB Bandwidth dc to 100 kHz External dc bands 1 5 thru 10 Depth lt 90 20 Hz to 100 kHz External ac and internal bands 1 5 thru 10 dc to 20 kHz External dc bands 2 3 4 20 Hz to 20 kHz External ac and internal bands 2 3 4 Incidental 0 2 radians peak 1 kHz rate and 30 AM 5AM bandwidth is increased to 100 kHz in these bands by using Special Function 8 prefer HET band rev O7 JUNESS5 1 8 1 Model 8642A B General Information Table 1 1
87. phase noise of both 8642s Therefore the LO must have SSB phase noise that is less than or equal to the specification for the HP 8642 under test SPECTRUM OSCILLOSCOPE ANALYZER F GENERATOR RF HP 8642A B SYNTHES ZED SIGNAL GENERATOR SIGNAL LOW NOISE AMP Figure 4 12 SSB Phase Noise Test Setup Optional 4 38 Performance Test 12 rev 08J UL88 Model 8642A B Performance Tests Equipment MiXer 2n2onisvos ua Se bei e Decret kaws s d s u h aq chus HP 10514A EMHZ Low Pass Filterer aroan ssi ha eS et ig de ev stus uU Eie e DUE See Figure 1 Low Noise Amplifier W Power Supply HP 6216A HP 08640 60506 Spectrum Analyzer ene hn rm E RE Re a ERE dated MR ERE eeu dee HP 8566A Oscilloscope i uc n vct eee diss ek I eU HP 1980B PUER HP 8642B Procedure 1 Connect the instruments as shown in Figure 4 12 On the LO select external DC FM and 1 kHz FM deviation Insure that the spectrum analyzer center frequency calibration is accurate NOTE The following symbols are used in the procedure fgg the RF output frequency where SSB phase noise will be checked forpr the frequency offset from faz where SSB phase noise will be checked 2 Set the LO s frequency to faz and the output level to 16 dBm Set the HP 8642 under test to fkr forpr and the output level to 50 dBm 3 Set up the Spectrum Analyzer as follows VIDEO BW tto d saat and ns h
88. pulse for oscilloscope display blanking during retrace The line fuse X AXIS output provides a O to 10 Vdc 10 stepped output for use with an external oscilloscope Optional rear panel outputs and inputs Option 002 Back up instrument calibration data is stored in a circuit board located in this housing 10 MHz OUT is locked to the reference oscillator in use Figure 3 2 Rear Panel Features Mode 8642A B Operation HP IB CONTENTS HP IB REMOTE OPERATION 3 7 HP IB ADDRESS 3 8 Available Addresses 3 8 To Display the Current Address 3 8 ENT ADRS 2253 2 u OPES Iu 3 8 To Change the Address 3 8 HP IB CAPABILITIES 3 9 OvervieW c hse oni eee es ep VISION E 3 9 HP IB Capabilities 3 9 Table 3 1 HP IB Capability ReferenceTable 3 10 DATA INPUT 3 11 Overview L L ug aka h u cr ptum 3 11 Table 3 2 Data Input Example 3 11 Program Codes 3 11 Input Syntax sese 3 11 Table 3 3 Relationship Between Keystrokes and HP IB Code Sequences erea tir cece cence en 3 12 Sequence Dependency 3 12 Figure 3 3 Flowcharts for Sequence Dependency 3 13 Valid Character Entry
89. return the display to instrument settings previously displayed press the key twice The SPCL annunciator indicates the current use of a Special Function 3 41 Operation Model 8642A B RF Frequency cont d HP IB Codes Comments Underranging Specified Frequency RF frequencies as low as 1 Hz can be selected However the Signal Generator s signal characteristics are not specified below 100 kHz below 10 kHz the output level falls rapidly The Signal Generator will not allow overrange settings settings above 1057 500000 MHz for the 86424 or above 2115 000000 MHz for the 8642B Selecting the Het Band Increases Specified AM Rates AM depths are specified for depths less than or equal to 904 at a maximum rate of 20 kHz in the RF frequency range from 4 130860 to 33 046875 MHz You can increase specified AM rates in this carrier frequency range from a maximum of 20 kHz to a maximum of 100 kHz by selecting Special Function 8 Prefer Het Band The Signal Generator will not automatically select the Het Band in this case Related Special Functions 240 Decrement Frequency by 0 1 Hz 241 Increment Frequency by 0 1 Hz These functions change the RF signal s output frequency in 0 1 Hz steps each time the special function is selected For example selecting SPCL C 2 CL increments output frequency by 0 1 Hz The Signal Generator cannot directly display this RF frequency increase or decrease 1n its normal
90. scale There is no start of sweep settling time when this special function is selected Also Z AXIS is always TTL low 221 Sweep Up and Down Off This special function re enables the normal sweep that is disabled with Special Function 121 Special Function 221 sets the Signal Generator to sweep from the start end point to the stop end point and then again from the start end point to the stop end point NORMAL SWEEP MODE UP AND DOWN SWEEP MODE 2 2 a a 2 2 o o t Uu H w gt gt lt 4 lt 1 gt gt Figure 3 10 Sweep Waveforms Operation Model 8642 Amplitude Sweep 122 Linear Amplitude Sweep This special function selects linearly stepped output rather than the usual logarithmicly stepped output Use a sweep time greater than 900 ms to obtain maximum sweep resolution 222 Logarithmic Amplitude Sweep This special function selects the usual logarithmicly stepped output disabled with Special Function 122 Related Operating Instructions Refer to Knob page 3 14 1 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Instrument Preset Partial Preset page 3 139 for information on setting the instrument to an initialized state that maintains preset references including the selected amplitude units Refer to Operating Messages page 3 17 7 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 f
91. setting Select only EREG or CAMPTD J HP IB FR or AP before attempting relative settings AP REF DISALLOWS DBUV E34 4034 An amplitude reference cannot be set in dBuV Set amplitude to the desired value in dBuV then select REL ZERO HP IB APRZ AP SWP DISALLOWS DBU V E35 4035 An amplitude sweep cannot be directly set in dBuV Convert the desired dBuV setting value to absolute units then set the amplitude sweep in absolute units Refer to page 3 205 for amplitude units conversion information FM COUPLED FUNC LIMIT E38 4038 FM is coupled with an attempted setting You are either attempting a setting that is impossible or attempting to set functions in an incorrect order This message could also have been caused by executing Special Function 0 or 100 when one special function was coupled to other instrument settings Possibly refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III INT EXT FM PREVENT SP6 E39 4039 Special Function 6 FM Pre Emphasis cannot be selected when an internal source is summed with an external source Select a single FM source NIJ CEXT AC J EXT DC or Special Function 5 HP IB FMNT FMXA or SP5 before selecting FM Pre Emphasis or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III PM LIMITS MIN FREQ E40 4040 The M setting limits the minimum RF frequency value that can b
92. setting of the other Either set deviation to a value that is allowed by start and stop frequencies or set start and stop frequencies to values that allow the setting or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of Section III rev 20MAR85 3 189 Operation Model 8642 Operating Messages cont d AMPTD SPAN 30DB MAX E63 4063 An ampltude span of 30 dB is the maximum possible span Either select an amplitude sweep setting within the 30 dB span limitation or turn off the other amplitude sweep start or stop value HP IB AAOF or ABOF AP SWP LIMITS MIN TIME E64 4064 The minimum sweep time possible for amplitude sweep is 20 ms Either select another sweep time or turn off amplitude sweep HP IB AAOF ABOF AP SWP PREVENTS SP9 E65 4065 Special Function 9 Attenuator Range Hold is not possible during amplitude sweep Turn off amplitude sweep HP IB AAOF ABOF and set amplitude HP IB AP before selecting attenuator range hold HP IB SP9 SP9 PREVENTS AP SWP E66 4066 Amplitude sweep is not possible when Special Function 9 Attenuator Range Hold is selected Select Attenuator Range Hold Off Special Function 209 before selecting amplitude sweep AM PREVENTS AP SWP E68 4068 Amplitude sweep is not possible when AM is selected Turn off AM HP IB AMOF before selecting amplitude sweep AP SWP PREVENTS AMPTD E69 4069 Output amplitude cannot be set during amplitude sweep
93. specific sequence for entry Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III Display z3 ra FA TA iu mnsBadaadggdasu FREQ v 2 qusdam EXT DC AMPTD The RF output is being externally phase modulated with an external dc coupled source as indicated by the EXT and DC annunciators deviation setting is 2 00 radians per volt Modulation frequency is not monitored by the Signal Generator when an external modulation source is used The cursor above the setting indicates is the active function HP IB Keys Codes Cos INT EXT MOD FREQ OFF ON PMOF PMON INT rad EXT AC kHz EXT DC Hz INT EXT AC SPCL Comments Modulation Types Not Possible During RF Frequency Sweep During Stepped Frequency Sweep FM and are allowed in manual or single sweep mode only During Phase Continuous Frequency Sweep Special Function 123 all modulation types are allowed Modulation Switching Time The time required to turn on the internal modulation oscillator or to switch between modulation frequencies can be reduced by approximately 200 ms depending on modula tion frequency with a loss in modulation frequency accuracy by selecting Modulation Frequency Correction Off Special Function 113 For more information refer to Speeding Up Modulation Switching Time on page 3 132 rev 20MAR 85 3 123 Operati
94. state in the next available register register 06 program codes After the key is pressed the display returns to show the current instrument settings 3 158 Model 8642A B Operation Save Recall cont d RECALL How to Recall an Instrument State To recall the instrument state from a specific register RECALL J followed by the two digit number of the desired register To recall the instrument state from the next available register for example to recall and modify registers 1n sequence RECALL t To recall the most recently saved or recalled register for example to get back to a previous state before it was modified CRECALL Recalling the last register in this way can get back to a recalled state after modifying settings HP IB Codes SAVE SV SVUP SVDN RECALL RC RCUP RCDN Comments HP IB Exactly two digits must always be used for Save Recall register numbers Editing the Sequence State If a change is desired in a register that is saved the key can be used to save the changed instrument state For example if as part of a saved instrument state an output amplitude of 10 dBm was saved in register 06 this amplitude can be changed to 20 dBm The following procedure might be used to change the setting in that recall register BECALL C CAMPTD C2 CO SHZ DBM SAVE C2 How Save Recall Affects the Next Sequence Register Number Saving a register will no
95. step size of 8 MHz you can set the sweep time between the results of the following calculations P X 135 ms 6885 ms or 6 885s 100 500 X 135 ms 7020 ms or 7 020s SWEEP SWEEP TIME START FREQ Ct Co Co EA CI C8 program FASA ST 7 SC FA 100 MZ FB 500 MZ codes These codes are not indejendent and might need to follow a specific sequence for entry Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III Display 3 3 a bd ig um S 5gB 5dddd START FREQ SWPNG STOP The display usually shows the start frequency and the stop frequency settings If another active function is seler ted the display could indicate frequency sweep with the SWPNG annunciator or by displaying FRQ SWEEPING in the left portion of the display above the FREQ annunciator To actually see the 8 MHz steps on the display you can select manual sweep and turn the Knob slowly or use the Step keys Operation Model 8642A B RF Frequency Sweep cont d How to Set Sweep Time for Phase Continuous Frequency Sweep Special Function 123 Understanding Limitations Between Sweep Spans and Sweep Times Also How to Set a Specific Number of X Axis Steps The operating characteristics for sweep time are as follows Minimum Sweep Time Refer to calculation 3 on page 3 61 Maximum Sweep Time Refer to calculation 4 on page 3 61 Sweep Time Resolution 1 ms
96. the following data messages when it is addressed to talk Status Byte refer to Status Byte on page 3 29 Messages discussed below Display Information dis ssed below Service Messages refer to Section the Service Manual for specific Service Message information The Signal Generator can output the following messages and display information normally viewed on the front panel display using HP IB codes that do not have equivalent front panel ys ihe HP IB codes are in parenthesis after each message listed below Output Messages Hardware Errors OH Execution Errors OE Parameters Changed Messages OC Output Active Function OA Output HI 1 O Status OL Output Display Output Display is the default HP IB output when nothing else is configured for data output it does not require an HP IB code to output data Operation x Model 8642A B Data Output cont d Output Messages Hardware Errors OH These messages signal the presence of either an internal circuit hardware problem or a firmware problem Refer to Messages page 3 177 for more information about these messages each message code is prefixed with the letter H in the listing in that section The presence of one or more of these messages 1s signaled when bit 1 of the Status Byte is set Refer to Status Byte on page 3 29 Some service related messages can also cause this bit to be set Refer to the Service Manual Execution Errors OE
97. the hardware error refer to the Service Manual for more information HIT AMPTD CLEAR RVSPWR H1 7001 Press the AMPTD key to reset the reverse power protect circuitry A reverse power condition has been sensed After this condition is eliminated select the AMPTD key to reset the protection circuitry HP IB Send AP after the condition is eliminated Message H2 will always occur after the reverse power protect circuitry is reset in response to message RVS PWR PROTECT CLEARED H2 7002 The reverse power protect circuitry was previously tripped but is now reset RECALL ERROR FOUND H10 7010 A recall error has been found This message could be due to a hardware failure for example loss of RAM memory The message means that a recall register that was recalled had no instrument settings saved in it The register could have been cleared with Special Function 251 Clear Recall Registers or because of a hardware error This error H10 occurs in conjunction with execution error E93 Refer to Recalling an Undefined Register on page 3 162 for more information MSSG BUFFER OVERFLOWED 11 7011 The message buffer has overflowed Some messages were lost 10MHZ REF OVEN COLD H20 7020 The oven for the 10 MHz reference installed with option 001 is cold The frequency reference could be unstable until the oven is warm When the oven cold condition no longer exists an attempt to scroll through the message list twice will not display the messag
98. to the maximum use a sweep time setting in ms equal to or greater than the result of the following equation Number of Steps 1 X 3 ms If the desired number of steps is less than the maximum calculated in 3a use a sweep time setting in ms greater than or equal to the result of the above calculation but less than the result of the following calculation Number of Steps 2 X 3 ms Operation Model 8642 Amplitude Sweep cont d Example for Calculation 3 Set an amplitude sweep from 10 dBm to 21 dBm with 100 amplitude steps Calculate the required sweep time setting for the 100 amplitude steps using calculation 3 Maximum number of steps is equal to 10 dBm 21 dBm 0 1 dB b Minimum number of steps is equal to a minimum of 5 or 10 dBm 21 dBm 110 0 1 dB Since 5 is less than 110 the minimum number of steps is 5 Therefore it should be possible to select 100 steps since that value is between the minimum value 5 and maximum value 110 To get 100 amplitude steps you can set the sweep time between the results of the following calculations 100 1 x 3 ms 303 ms 100 2 X 3 ms 306 ms TIME START START AMPTD FREQ SWEEP DATA DATA START GHz GHz O a Eo EJ lt program codes AASA ST 304 MS AA 10 DM AB Model 8642A B Operation Amplitude Sweep cont d Example for Calculation 3 cont d Display CRUNCH CRUNCH mmm IBB The d
99. 002 Rear Panel Output for All Connectors This option places all front panel connections on the rear panel of the instrument HP 8642A Option 003 Increased Output Power Option This option enables the HP 8642A Synthesized Signal Generator to deliver the same output power as the HP 8642B excluding band 10 Mechanical Options Option 907 Front Handle Kit Front handles are provided when Option 907 is ordered Order a Front Handle Kit as HP part number 5061 0089 Option 908 Rack Flange Kit Rack flanges are provided for the Signal Generator when Option 908 is ordered When rack mounting the Signal Generator ensure the instrument is supported properly by using the system cabinet s support rails Due to the weight of the HP 8642A B not using the support rails could cause damage to the instrument and or the system cabinet Order a Rack Flange Kit as HP part number 5061 0077 Option 909 Rack Flange and Front Handie Combination Kit This is not a Front Handle Kit and a Rack Flange Kit packaged together it is a unique part that combines both functions Combination kits are provided for the Signal Generator when Option 909 is ordered When rack mounting the Signal Generator ensure the instrument is supported properly by using the system cabinet s support rails Due to the weight of the HP 8642A B not using the support rails could cause damage to the instrument and or the system cabinet Order a Rack Flange and Front Handle Combination Ki
100. 06 125 9E 09 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 125 9E 15 12 59E 15 1 259E 15 251 2E 18 100 0E 03 79 43E 03 12 30E 03 3 981E 03 1 259E 03 125 9E 06 12 59E 06 1 259E 06 125 9E 09 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 125 9E 15 12 59E 15 1 259E 15 251 2E 18 Performance Test Record Model 8642A B Measuring i Results watts HP 8642 3642 FREQ Receiver Measuring MHz Fregu nc Receiver RF POWER 39 81E 03 63 09E 03 RF POWER 31 62E 03 50 12E 03 RF POWER 7 762E 03 12 30E 03 RF POWER 2 510E 03 3 981E 03 TUNED RF 794 3E 06 TUNED RF 79 43E 06 TUNED RF 7 943E 06 TUNED RF 794 3E 09 TUNED RF 79 43E 09 1 259E 03 125 9E 06 12 59E 06 1 259E 06 125 9E 09 TUNED RF 7 943E 09 TUNED RF 794 3E 12 TUNED RF 79 43E 12 TUNED RF 7 943E 12 TUNED RF 794 3 15 12 59 09 1 259 09 125 9 12 12 59 12 1 259 12 TUNED RF 79 43 15 TUNED RF 7 943E 15 TUNED RF 794 3E 18 TUNED RF 158 5E 18 TUNED RF 125 9E 15 12 59E 15 1 259E 15 251 2E 18 TUNED RF 79 43E 06 TUNED RF 7 943E 06 TUNED RF 794 3E 09 TUNED RF 79 43E 09 125 9E 06 12 59E 06 1 259E 06 125 9E 09 TUNED RF 7 943E 09 TUNED RF 794 3E 12 TUNED RF 79 43E 12 TUNED RF 7 943E 12 TUNED RF 794 3E 15 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 TUNED RF 79 43E 15 TUNED RF 7 943E 15 TUNED RF 794 3E 18 TUNED RF 158 5E 18 TUNED RF 125 9E 15 12 59E 15 1 259E 15 251 2E
101. 1 Data Input 3 11 Data Output 3 15 DB and DM 3 76 Device Clear DCL 3 9 Display current address 3 8 Display indicators 3 31 End of sweep 3 28 ENT ADRS 3 8 3 34 Entering a user defined message 3 202 Entry notation 3 14 Error code recovery 3 16 Error 3 28 Execution Errors 3 16 Front panel keys 3 34 Go To Local GTL 3 25 Hardware Errors 3 16 HI LO status 3 20 Input syntax 3 11 INT RQS MASK 3 34 Listen address status 3 9 Listen only 3 8 Local lockout set local 3 26 Local to remote 3 25 LOCAL 3 25 3 34 Local remote 3 28 LSTN 3 11 MANUAL sweep 3 64 3 92 Message recovery 3 23 Messages affected by instrument preset 3 138 Messages affected by partial preset 3 139 Messages 3 16 3 16 Modulation switching time 3 132 OA 3 18 OC 3 16 3 210 Model 8642A B HP IB continued OE 3 16 OH 3 16 OL 3 20 Output active function 3 18 Output display information 3 21 Output Execution Errors 3 16 Output Hardware Errors 3 16 Output HI LO status 3 20 Output level switching time 3 73 Output messages 3 16 Output modulation source 3 22 Output Parameters Changed Messages 3 16 Output special functions 3 22 Parameters Changed Messages 3 16 Program codes 3 32 Ready 3 28 Remote to local 3 25 Require Service 3 27 Reset status bits 3 24 3 30 RMT 3 8 RQS mask affected by instrument preset 3 138 RQS mask affected by partial preset 3 139 RQS MASK 3 27 3 34 Selected Device Clear SDC
102. 1 Hz 241 Increment Frequency by 0 1 Hz These special functions change the RF signals output frequency in 0 1 Hz steps each time the special function is selected Changing frequency in these ways cause a message to be queued up in the message list that provides the total increment or decrement Refer to RF Frequency page 3 42 242 Phase Decrement 1 Degree 243 Phase Increment 1 Degree 244 Phase Decrement 5 Degrees 245 Phase Increment 5 Degrees These functions change the RF signal s output phase by the indicated amount each time the special function is selected For example selecting SPCL SSHET 2 2 4 C4 decrements output phase by 5 degrees Operation Model 8642A B Special Functions cont d DETAILED DESCRIPTIONS OF ALL SPECIAL FUNCTIONS cont d 248 Calibrate the Modulation Frequency Bands Again This special function enables you to initiate the calibration sequence that normally only occurs during instrument power up This function can be used for example to recalibrate the modulation oscillator frequency bands if normal modulation frequency correction has been disabled with Special Function 113 Calibration typically takes one to two seconds Refer to Modulation Frequency page 3 133 249 Display Firmware Information This special function displays the current firmware version with a message such as YYMMDD FIRMWARE CODE 13 In this example YYMMDD represents the numbers that will appear in the display whe
103. 1251 8248 1251 8105 1251 8823 08642 20041 11801 90202 11801 90204 08642 40073 9300 0980 2140 0536 08642 90020 9320 3944 11801 90001 34118A 08642 00070 8730 0012 9300 0985 1250 0781 1250 0837 08642 80053 1251 5653 0 2 7 8 6 5 9 1 3 9 2 7 1 Bann nn ns m Case Large Case Small Connector Ribbon Cable 34 Pin Connector Ribbon Cable 26 Pin Connector Ribbon Cable 16 Pin Connector Ribbon Cable 14 Pin Extender Post Foam Top and Bottom for large case Foam Top and Bottom for small case Fuse Puller Grounding Strap Anti Static Lamp Incand 5 Vdc 115 mA T 1 Bulb On Site Service Manual Storage Box Plastic 1 Compartment Storage Box Plastic 10 Compartments Tag Blue Stripe Tag Defective Test Lead Kit Wrench RF Connector Wrench Torque Wristband Antistatic BNC Tee f m m SMC Tee m m m Power Supply Test Connector Connector Ribbon Cable 50 Pin Model 8642A B General Information 161 a n n n G M Y M W n 10 19 2 HHH JUR Lien fier Fat ner herbas deni Par Description 1 2 3 4 5 6 7 8 9 10 Not Shown Not Shown Not Shown Not Shown Not Shown Not Shown Not Shown 11 12 13 Not Shown 14 15 Not Shown 16 17 18 19 20 21 22 23 24 25 26 1250 0832 1250 0827 1250 1200 1250 0838 8710 0630 8710 0033 8710 1515 8710 1465 8710 1493 8710 1541 08642 60135 08642 60137 0864
104. 132 Comments o desy hows kq c5 pe eure 3 132 Related Special Functions 3 133 113 Modulation Frequency Correction Off 3 133 248 Calibrate the Modulation Frequency Bands Again un aa ma 3 133 3 95 Operation Model 8642A B MODULATION 86428 SIGNAL GENERATOR 0 1 2100 MHz These keys make AM FM or the active function so its value can be set using either Data keys the Knob Step keys or the Off On key Also Pulse Modulation can be turned on or off You can select either AM or Pulse Modulation simultaneously with either FM or Modulation Source keys select whether internal pac o or external source is used or internal and external E sources combined The source of the external ote modulation is coupled through the input connectors The key is used to set the modulation frequency for all internal modulation sources and for the modulation output The key is also used to set the modulation br output level for the Mod Output connector DATA EE LEE a 1 ta These terminator keys enable you to complete a data entry Ca ms mp rz Figure 3 11 Modulation Related Functions 3 96 Model 8642A B Operation MODULATION AM Description The Signal Generator can amplitude modulate its RF output either with a variable internal modulation oscillator and or with an ac or dc coupl
105. 16 117 DC FM Update Mode On With the FM loop unlocked RF output frequency changes with a change in applied dc signal and with the normal drift of an unlocked VCO that occurs over time and temperature In the DC FM Update Mode the Signal Generator measures these changes in RF frequency and displays the changing RF output frequency on the display DC FM Update Mode requires continuous microprocessor and counter action resulting in a slight increase in noise spurious signals and radio frequency interference RFI These increases do not degrade specifications The time required to turn on the internal modulation oscillator or change modulation frequency is increased by approximately 200 ms for all internal modulation types when the DC FM Update Mode is selected With Special Function 117 selected during RF frequency sweep changes in RF frequency are not reflected on the display During Phase Continuous Frequency Sweep Special Function 123 dc coupled FM is not possible when DC FM Update Mode is on 217 DC FM Update Mode Off This special function disables the DC FM update that occurs with Special Function 117 118 AC Coupled DC FM On When the Signal Generator is in the normal ac coupled FM mode the external signal is applied to the FM loop through circuitry that uses a phase lock loop to ensure the accuracy of the output signal In dc coupled FM DC FM the phase lock loop is unlocked and the external signal is applied directly to the
106. 2 60134 08662 60080 08662 60075 11802 90202 11802 90201 1251 5653 1251 8601 1251 8248 1251 8812 1251 8105 1251 8823 1252 0153 1250 0839 1250 1598 08642 40073 08642 60951 08642 60078 08642 60079 08642 20089 08642 00070 9300 0980 8730 0012 9300 0985 N O O Q Q O Q O QG O NN O Adapter Coax STR Female BNC to Female SMC Adapter Coax STR Male SMC to Male SMC Adapter SMA to BNC Adapter Tee Female Male Male SMC Alignment Tool Screwdriver 08 Alignment Tool Screwdriver 075 Alignment Tool Square 030 Bit Torx T10 Bit Torx T15 Bit Torx T5 Board Assembly Latch Extender Board Assembly Processor Extender Board Assembly Signature Analysis Cable Assembly Short Cable Assembly Service Kit Long Case 20 8 x 14 8 Foam Top and Bottom Connector Ribbon Cable 50 Pin Connector Ribbon Cable 34 Pin Connector Ribbon Cable 26 Pin Connector Ribbon Cable 20 Pin Connector Ribbon Cable 16 Pin Connector Ribbon Cable 14 Pin Connector Ribbon Cable 10 Pin Terminal Female SMC Connector Male SMC RF Fuse Puller Probe 4 Pin Mixer Probe 8 Pin Mixer Probe 8 Pin Power Splitter Reference Sum Loop RF Connector Wrench Strap Anti static Grounding Wrench Torque 2 4 Newton meters Wristband Anti static Figure 1 2 Bench Service Kit 1 19 DECLARATION OF CONFORMITY according to ISOAEC Guide 22 end EN 45014 Manutact
107. 20 dBm Vertical Seale u een u a Vie wh Wad RE EA aia 10 dB div 2 Rise Fall Time Set the HP 8642 RF frequency to 1000 MHz amplitude to 13 dBm and turn on external dc pulse modulation On the Oscilloscope verify that the recovered modulation pulse on channel B rises from 10 of the final value to 90 of the final value within 0 40 us Record the reading below Rise Time On Off Ratio Change the equipment to Setup A in Figure 4 13 There should be a broad trace that covers the top half of the spectrum analyzer display The top of the trace is the pulse on amplitude and the bottom is the pulse off amplitude determine the difference in level and verify that the value is within the specified limits given in the table below Results RF Frequency a e nee 1000 0 30 0 2000 0 45 0 Performance Test 13 rev 08JUL88 Model 8642A B Performance Tests Performance Test 14 OPTIONAL RESIDUAL FM TEST Specification Electrical Characteristics Performance Limits Residual AM 5 Hz rms band 10 0 3 to 3 kHz BW 2 band 9 12 band 8 lt 1 band 1 7 lt 3 5 band HET Residual FM lt 9 0 Hz rms band 10 00 5 to 15 kHz BW lt 5 0 band 9 lt 2 0 band 8 lt 1 2 band 1 7 lt 5 0 band HET Description The Performance Test 4 Residuals Test gives 99 confidence that the HP 8642 is passing all its Residual FM specifications However if a measurement bandwidth of 50 Hz to 15 kHz is requ
108. 240 241 242 243 244 245 248 249 250 251 99 130 t gt WO Operation Summary vf Special Functions Code to Function SPCLS 4 9 OFF SER VICE MODE SEE MANUAL ALC OFF EXT LOW RATE FM ON FM PRE EMPHASIS ON LOW DISTORTION FM PM ON PREFER HETERODYNE BAND ATTEN RANGE HOLD ON ALL SPCLS lt 200 OFF SPCL FUNC VERIFY OFF INT EXT LOW RATE FM ON MOD FRQ CORRE ION OFF NEGATIVE PM POLARITY NEGATIVE FM POLARITY DCFM CORRECTION OFF DCFM UPDATE MODE ON AC COUPLED DCFM ON DISABLE SETTLING SWEEP UP AND DOWN ON LINEAR AMPTD SWEEP PHASE CONTINU JS SWP TURN OFF LCD LIGHTING DISABLE DISPLAY DECR FREQ 0 1 HZ INCR FREQ 0 1 HZ PHASE DECR 1 DEGREE PHASE INCR DEGREE PHASE DECR 5 DEGREES PHASE INCR 5 DEGREES CAL MOD FREQ AGAIN DISPLAY FIRMWARE INFO PHASE ADJ KNOB UP DN CLEAR RECALL REGS DISABLE ALC OFF EXT LOW RATE FM OFF FM PRE EMPHASIS OFF LOW DIST FM PM OFF PREFER DIVIDE BANDS ATTEN RANGE HOLD OFF SPCL FUNC VERIFY ON INT EXT LOW RATE FM OFF MOD FRQ CORRECTION ON POSITIVE PM POLARITY POSITIVE FM POLARITY DCFM CORRECTION ON DCFM UPDATE MODE OFF AC COUPLED DCFM OFF RE ENABLE SETTLING SWEEP UP AND DOWN OFF LOG AMPTD SWEEP PHASE CONT SWEEP OFF TURN ON LCD LIGHTING RE ENABLE DISPLAY 3 171 Operation Model 8642A B Special Functions cont d DETAILED DESCRIPTIONS OF ALL SPECIAL FUNCTIONS 0 Special Functions 4 through 9 Off This special function turns off Special Functions 4 through
109. 248 Single Modulation Frequency Correction 249 Display Firmware Information 250 Phase Adjust on Knob and Steps 251 Clear the Recall Registers Note Put the instrument in its initialized state by selecting INSTR PRESET How to Save an Instrument State To save the current instrument state 1n a specific register CSAVE followed by the two digit number of the desired register To save the current instrument state in the next available register for example to set up instrument states to use with the Sequence function CSAVE Ct To save the current instrument state in the most recently accessed save recall register for example to re save an instrument state after recalling and modifying it SAVE QJ 3 157 Operation Model 8642A B Save Recall cont d Example First set the Signal Generator s frequency to 10 MHz and set the output amplitude to 10 dBm CEREQ 1 CQ MHZ V AMET C1 CO CGHZ DEM Save this instrument state in register 05 First x program codes Note the UP 01 and DN 00 prompts These show the current register number of DN 00 and the next register number 01 When you enter the register number the spaces next to the word SAVE will be filled Select 0 C5 When the register number is entered the display returns to show the current instrument settings Now set the output frequency to 500 MHz FREQ 5 CO 0 Save this instrument
110. 25 12 06 166 666667 500 05 25 12 06 250 000000 500 0 25 12 06 2000 000000 1000 086 316 2 09 500 000000 1000 0 25 12 06 333 333333 1000 0 25 12 06 2 5 6 On the HP 8902A Measuring Receiver press blue SHIFT RECALL followed by the numeric key indicated by the note number 4 10 Performance Test 2 rev 08JUL88 Model 8642A B Performance Tests Performance Test 3 PULSE ON OFF RATIO TEST Specification On Off Ratio gt 40 dB band HET 9 gt 80 dB band 10 DESCRIPTION Pulse On Off Ratio is measured by using the measuring receiver to measure the power output of the HP 8642 without modulation and in Pulse mode with no modulating signal The ratio is measured at worst case frequencies for the HP 8642 MEASURING EET C EP HP 8642A B SYNTHESIZED SIGNAL GENERATOR MODULE Figure 4 3 Pulse Test Setup EQUIPMENT Measuring Receiver ERE UE In DICE eI Tere HP 8902A Sensor ecoute ot a aypa Sha sa US Ce aed Tons SS aa gy o canes HP 11722A PROCEDURE Setup 1 Connect the instruments as shown in Figure 4 3 2 Preset the instruments 3 Set the measuring receiver to tuned RF Level mode If the Level Accuracy Performance Test has just been done with the same measuring receiver calibration is not required If Level Accuracy has not yet been done or you have changed measuring receivers then calibration is required Complete the following calibration p
111. 3 132 213 Modulation Frequency Correction On This special function re enables the modulation frequency correction disabled with Special Function 113 115 Negative FM Polarity This special function causes a positive voltage applied to the external FM M INPUT to cause a negative frequency shift and a negative voltage applied to cause a positive frequency shift 215 Positive FM Polarity This special function causes a positive voltage applied to the external FM M INPUT to cause a positive frequency shift and a negative voltage applied to cause a negative frequency shift Operation Model 8642A B Modulation FM cont d 116 DC FM Correction Off This special function prevents the initial frequency correction that occurs when dc coupled FM is selected When dc coupled FM is selected the FM phase lock loop is open causing an offset in the selected RF output frequency To correct this initial offset the dc coupled signal is momentarily switched off while an internal counter is used to determine the amount of RF frequency offset The frequency offset is corrected and the dc coupled signal is switched back on DC FM Correction Disabling this correction causes a decrease in switching time by approximately 200 ms During Phase Continuous Frequency Sweep Special Function 123 dc coupled FM is not possible when DC FM Correction is on 216 DC FM Correction On This special function re enables the correction disabled with Special Function 1
112. 3 9 Sequence dependency 3 12 Serial Poll Enable SPE 3 29 Service request 3 27 Set address 3 8 Set local 3 26 SHIFT key 3 11 Special functions 3 169 SRQ 3 27 Status bit clearing 3 24 3 30 Status bit 3 31 Status byte affected by instrument preset 3 138 Status byte affected by partial preset 3 139 Status byte clearing 3 27 3 29 Status byte 3 29 Talk address status 3 9 TLK 3 15 Trigger 3 31 HZ 3 208 INCR SET 3 149 INCR 3 142 Increment set 3 149 Input data 3 9 INSTR PRESET 3 138 Instrument preset partial preset 3 137 Internal source see modulation oscillator 3 131 INT AM 3 98 FM 3 107 3 120 Pulse Modulation 3 127 K Key functions 3 35 Knob hold 3 148 Model 8642A B Knob increment 3 142 KNOB 3 141 KZ 3 208 L Learning the 8642A B 3 1 Line fuse 3 1 3 3 LO annunciator 3 98 3 108 3 122 LOCAL 3 25 3 34 LSTN annunciator 3 207 M MANUAL sweep from HP IB 3 64 3 92 MANUAL sweep mode Amplitude 3 84 Frequency 3 51 Messages 3 179 Detailed list 3 181 Queued up 3 180 That occur when writing user defined messages 3 204 Transient 3 180 User defined 3 201 Writing to the display 3 201 MOD FREQ 3 131 MOD OUT 3 131 MOD OUTPUT 3 131 MOD OUTPUT output phase 3 133 Modulation frequency see modulation oscillator 3 131 Modulation oscillator 3 131 Spurs 3 133 Switching time 3 132 Underranging 3 133 Modulation source 3 95 Modulation AM see
113. 3438 33 046875 MHz 8 261717 16 523427 MHz 4 130860 8 261718 MHz 0 100000 4 130859 MHz 0 100000 132 187500 MHz 1 Hz 0 1 Hz with Special Function 240 or 241 Resolution Stability Same as reference oscillator INTERNAL REFERENCE OSCILLATOR Standard Option 001 Aging Rate See Supplemental Characteristics 10 7 day After 8 day warm up SPECTRAL PURITY SSB Phase Noise CW AM or Angle Modulation lt 1 60 Maximum Peak Deviation SSB Phase SSB Phase Noise 20 kHz Noise Floor offset from 200 kHz offset carrier from carrier 0 125 dBc Hz 134 dBc Hz 9 134 dBc Hz 143 dBc Hz 8 137 dBc Hz 144 dBc Hz 7 141 dBc Hz 144 dBc Hz 6 144 dBc Hz 145 dBc Hz 5 145 dBc Hz 145 dBc Hz 4 146 dBc Hz 147 dBc Hz 3 147 dBc Hz 148 dBc Hz 2 148 dBc Hz 149 dBc Hz 1 134 dBc Hz 135 dBc Hz ET 125 dBc Hz 137 dBc Hz Both generators cover their ranges in one continuous span However many other specifications are dependent on carrier frequency To simplify such specifications the 8642A and 86428 carrier frequency ranges are divided into bands Band 9 86428 carrier frequency ranges is 528 7500005 MHz to 1057 500000 MHz rev 100JAN9I Jaf General Information Model 8642A B Table 1 2 Specifications 2 of 6 Electrical Characteristic Performance Limits conditions SPECTRAL PURITY Cont d Residua
114. 3E 15 TUNED RF 794 3E 18 TUNED RF 158 5E 18 TUNED RF 125 9E 15 12 59E 15 1 259E 15 251 2E 18 RF POWER 31 62E 03 RF POWER 7 762E 03 RF POWER 2 510E 03 RF POWER 794 3E 06 RF POWER 79 43E 06 RF POWER 7 943E 06 50 12bE 03 12 30E 03 3 981E 03 1 259E 03 125 9E 06 12 59E 06 1 On the HP 8902A press CALIBRATE before continuing test 6 7 On the HP 8902A press blue SHIFT STORE followed by the numeric key indicated by the note number 8 HP 8642B only 9 HP 8642A only 4 8 Performance Test 1 rev 08JUL88 Model 8642A B Performance Tests Performance Test 2 HARMONICS TESTS Specification Electrical Characteristics Performance Limits Conditions Harmonics 16 dBm 10 dBm band 10 lt 10 dBm band HET 9 Sub harmonics band HET 9 band 10 Description The HP 8642 s frequency is set to values where harmonic performance problems are most likely to be observed The measuring receiver is used to measure the power level at the harmonic or sub harmonic frequency To do this the measuring receiver must have been calibrated over the full power measurement range at that frequency Doing the Level Accuracy Performance Test automatically does this For troubleshooting purposes or characterization of other RF frequencies a spectrum analyzer may be used 00 dae BR 888 O ee RECE VER FRU N SIGNAL GENERATOR MODULE Figure 4 2 Harmonics Test Setup Equipment Measuring Receiver lico ves eser
115. 5 416 000 1012 000 000 976 000 000 562 000 000 1057 500 000 1057 500 000 563 000 000 85 870 000 3 700 000 0 430 000 4 560 000 5 870 000 45 000 000 225 000 000 112 500 000 596 313 600 599 078 400 572 796 000 612 171 000 747 608 000 776 836 000 781 840 000 799 536 000 967 076 000 788 000 000 742 500 000 606 500 000 1012 500 000 1057 375 000 540 500 000 Model 8642A B rev 08JUL88 Model 8642A B Performance Tests Performance Test 10 THIRD ORDER INTERMODULATION Specification Third Order Intermodulation 50 dBc 10 dBm two generators 25 kHz apart into a resistive combiner Description Intermodulation is checked by summing another Signal Generator and the HP 8642 into a spectrum analyzer The intermodulation products are then measured on the spectrum analyzer B BE OUTPUT UT ANALYZER HP 8642A B SYNTHESIZED SIGNAL GENERATOR Figure 4 10 Intermodulation Test Setup Equipment Spectrum Analyzers ene a u Pr curte P end pq ep v eR eio rea a e qo ee HP 8566B Power Splitter amu hex ease ie ha e ora aig Hr atrae Mew bye L8 a curio el HP 11636A Signal Generator ose cs aap taces iac Rn s HP 8642B 6 Pad MeL HP 8491A opt 006 reu 08J UL88 Performance Test 10 4 33 Performance Tests Model 8642A B 4 84 Procedure 1 2 3 Connect the instruments as shown in Figure 4 10 Preset the instruments Set up the HP 8642 as follows AMPLI
116. 50 kHz and inter nal rates 15 8 kHz FM Pre emphasis Special Function 6 Provides pre emphasis in FM with a 750 us time constant This is useful when testing FM communications receivers AMPLITUDE MODULATION for VOR ILS Avionics Applications AM Phase Shift DC Coupled for Carrier Frequencies From 108 MHz to 118 MHz 30 Hz rate lt 0 01 30 Hz to 10 kHz rate lt 3 Difference from 9 kHz to 11 kHz rates lt 2 AM Flatness DC Coupled External AM 0 04 dB 90 to 150 Hz 108 to 118 MHz and 329 to 335 MHz 0 00092 DDM 2096 AM and 0 0019 DDM 4096 AM 0 1 dB 9 to 11 kHz 108 to 118 MHz OUTPUT Absolute Accuracy 3 dB output level 127 dBm Output Level Switching Time 100 ms from receipt of last controller command Amplitude Sweep in CW and Angle Modulation Modes Range 20 dB log or linear with Special Function 122 sweep 10 dB underrange available Sweep Time 20 ms minimum 999s maximum Accuracy 1 dB over highest 10 dB 3 dB over sec ond highest 10 dB Attenuator Range Hold Special Function 9 The interna step attenuator can be fixed and the electronic level vernier varied up to 30 dB for monotonic level setting This is useful in measuring of receiver squelch hysteresis 1 13 General Information Model 8642A B Table 1 2 Supplemental Characteristics 2 of 2 Supplemental characteristics are typical but non warranted performance parameters intended to be use
117. 50000 MHz 132 187501 to 264 375000 MHz 66 093751 to 132 187500 MHz 33 046876 to 66 093750 MHz 16 523438 to 33 046875 MHz 8 261719 to 16 523437 MHz 4 130860 to 8 261718 MHz 0 100000 to 4 130859 MHz 0 100000 to 132 187500 MHz3 10 For crt display blanking during retrace 1 In AUTO sweep mode it is not possible to set start and stop end points if one end point is less than 4 130860 MHz band 2 with a second end point greater than 132 187500 MHz band 6 Also it is not possible to set a sweep across 1057 500000 MHz 8642B only 2 Maximum end point separation may be increased up to that shown for the HET band by selecting a frequency span larger than the span shown here HET band can also be selected with Special Function 8 3 The HET Band 4 Buffer this output in order to use the Z axis output with a plotter for pen lift 3 49 Operation Model 8642A B RF Frequency Sweep cont d Procedures Note Put the instrument in its initialized state by selecting INSTR PRESET How to Select Stepped Frequency Sweep SPCL 123 Stepped Frequency Sweep is turned on by selecting the sweep mode auto manual or single sweep time and the start and stop frequencies procedures for selecting these parameters are described below Note that 1f the sweep mode has not been selected since the last time Instrument Preset has been selected auto sweep is automatically selected and causes the Signal Generator to begin sweeping imme
118. 59 9 dBm 221V or 442 EMF Converting Amplitude Units Refer to Amplitude Units Conversion on page 3 205 for information about changing amplitude values from one unit to another When the dBm and dBuV Keys Function as dBuV Terminators Both the dBm key GHZ DBM and the dBuV key function as dBuV terminators when the amplitude is set in dBuV All other relative amplitude settings use only the dBm key as a dB terminator HP IB Either DB or DM When in the relative amplitude mode DM does not set dBm DM and DB set dB relative amplitudes Therefore amplitude relative must be turned off APRF to have DM mean dBm Conversions Are Automatic Relative settings established in the non EMF mode will be automatically converted to EMF values when that mode is selected Similarly relative settings established in the EMF mode will be converted to non EMF values when the EMF mode is turned off Amplitude Settings Interact With Other Instrument Settings Some settings are limited by the interaction of coupled functions for example AM depth and amplitude Refer to the appropriate Detailed Operating Instruction for setting limitations and be aware that any restrictions are due to the absolute amplitude not the relative amplitude setting 3 81 Operation Model 8642A B Relative Amplitude cont d Related Operating Instructions Relative Amplitude Sweep It is not possible to set an amplitude sweep directly in relative u
119. 8 MHz divide band 6 refer to Figure 3 13 on page 3 106 you can calculate the maximum allowed deviation to obtain the low distortion performance by multiplying 7 times 187 5 kHz 0 07 X 187 5 kHz 13 13 kHz To obtain a higher maximum deviation level you could select the Het band Special Function 8 which would have a maximum deviation of 7 times 1500 kHz 0 07 X 1500 kHz 100 5 kHz When using Special Function 7 external rates should be less than 50 kHz and internal rates should be less than 15 8 kHz If rates exceed these limits distortion may exceed 0 03 Total harmonic distortion is better than standard performance at all deviations and rates with this special function selected The phase noise performance is degraded by approximately 20 dB at a 20 kHz offset and by approximately 10 dB at a 200 kHz offset when in the Low Distortion FM M mode 207 Low Distortion FM M Off This special function switches out the shaper circuitry that is inserted with Special Function 7 113 Modulation Frequency Correction Off This special function disables the single band calibration of the modulation frequency oscillator that normally occurs whenever the modulation oscillator frequency is set or the internal modulation oscillator is put into use When this calibration is disabled the typical modulation frequency switching time is decreased by approximately 200 ms For more information refer to Speeding Up the Modulation Switching Time page
120. 9 Sometimes all these special functions will not be turned off if the instrument state is dependent on a special function A message will be displayed to notify you if a special function remained on after you selected Special Function 0 Special functions can also be turned off individually Refer to page 3 169 3 Service Mode See Manual This special function causes the Signal Generator to enter its service mode Refer to page 3 201 for information about writing messages to the display or refer to the Service Manual or the On Site Manual for information about servicing the instrument Select any function to exit this mode if this key was accidentally selected 4 ALC Off This special function opens the output leveling loop to provide typically 5 dB improvement in third order intermodulation at a 2 kHz offset Typical output level accuracy is 2 dB when ALC Off is selected 5 External Low Rate FM On 112 Internal External Low Rate FM On These special functions typically provide 0 4 Hz to 200 kHz external ac coupled FM with the Signal Generator remaining in a phase locked state Input coupling required for these functions makes the Signal Generator especially sensitive to dc voltage fluctuations Therefore relatively small dc voltage changes can cause the Signal Generator to lose phase lock requiring one to two seconds to regain the locked condition Special function 5 or 112 is turned off when another FM modulation source is selec
121. 96 20 kHz deviation 1 kHz rate 400 kHz carrier 3 dB Bandwidth int ext ac 20 Hz to 15 kHz ext dc dc to 15 kHz Description All AM FM and PM specifications are checked on a measuring receiver Distortion is checked by selecting the modulation mode and audio distortion mode e e ecg MEASURING oo 5 BB BBBEB O 5 RECE VER R HP 8642A B SYNTHESIZED SIGNAL GENERATOR ANU Figure 4 5 AM FM and PM Test Setup Equipment Measuring Receiver cocto tee a CARA p Tak riku aT ak ay rete tate ase HP 8902A Sensor Module uu yuy reno u RR EUER COR CRI ua ua HP 11722A Procedure Setup 1 Connect the instruments as shown in Figure 4 5 preset the instruments 2 Set the HP 8642 s output amplitude to 10 0 dBm rev 08JUL88 Performance Test 5 4 17 Performance Tests Model 8642A B 3 Set the measuring receiver as follows MEASUREMENT MODE e aa hh hm hh ns AM DETECTOR sedis sacs scenic td veins ae AERE PIU QUE E US or UE EM PEAK HP PIL TER ni REED ee cin aie au u ayau toe Re CERRO TRU a es en 300 Hz PP RIL ERIS UEPER Ane vee cate ey Sasa amare eared See OS 15 kHz FMUDE EMPHASIS owe Eat SUID WI ees OFF AM Indicator Accuracy 1 Set the HP 8642 AM to 90 2 Set the HP 8642 frequency to the values in the table below and verify that the measuring receiver readings are within the specified limits HP 8642 FREQ MHz 0 15 5 00 1050 13002 1 HP 8642A onl
122. A and above require HP 8642 Firmware Date Code 870601 and above for proper Auto Adjust operation 3 The HP 8642 serial number suffix must be greater than X XXXA00200 4 The HP 8902A used in some of the Auto Adjust routines must have 32 0 SPCL keyed into it before running the routine if it s firmware date code is 235 1985 or newer Key 42 0 SPCL into the HP 8902A to display the firmware date code NOTE If an HP 8642 does not have any of the above configuration restrictions and Auto Adjust difficulties arise please contact your local Hewlett Packard Service Center rev 20AUG87 5 2 1 Model 8642A B Adjustments How Ali Auto Adjust Procedures Begin At the beginning of each Auto Adjust routine you are requested to enter data The Module Tabs in Section 8 contain the Auto Adjust Procedures but for the first time user the beginning of the Auto Adjust routines is given below with some added explanation HD QQ RA Connect the required equipment to the HP 8642 via HP IB Verify or change the HP IB addresses of the external equipment as previously shown in Auto Adjust Routines On the HP 8902 or HP 8901B insure that the HP 11722 Cal Factors have been loaded into memory and the RF Power mode has been Zeroed and Calibrated Key in INST PRESET on the HP 8642 Key in SHIFT SPCL 3 to enter Service Mode Key in to make the HP 8642 a system controller Key in 0 to initiate the Auto Adjust mode A
123. AM 3 97 Modulation FM see FM 3 105 Modulation see 3 119 Modulation pulse see Pulse Modulation 3 127 MR abbreviation 3 208 MS abbreviation 3 208 MSSG 3 180 Multiple cursors 3 145 MV abbreviation 3 208 MZ abbreviation 3 208 OA 3 18 OE 3 16 OH 3 16 Operating messages see messages 3 179 Operator checks 3 1 Output data 3 9 Output level also see amplitude 3 69 P Partial preset 3 137 PARTIAL 3 139 PC abbreviation 3 208 Phase continuous frequency sweep 3 49 3 64 DC FM limits 3 65 Index 3 119 Deviation limits affected by heterodyne band 3 119 EXT AC EXT DC 3 121 INT 3 120 Modulation restrictions with other functions 3 123 Power up self check 3 137 Bypassing the 3 139 POWER 3 137 Pre emphasis 3 113 PULSE 3 127 Pulse Modulation 3 127 Duty cycle 3 127 EXT AC EXT DC 3 128 INT 3 127 Mixed modulation 3 130 Modulation restrictions with other functions 3 129 R RD abbreviation 3 208 Recall registers 3 157 3 161 RECALL 3 159 Recalling an undefined register 3 159 3 162 REF SET Amplitude 3 78 3 79 Frequency 3 46 REL OFF Amplitude 3 81 Frequency 3 46 REL ZERO Amplitude 3 77 Frequency 3 45 Relative amplitude 3 77 Display the reference 3 80 Range of settings 3 81 Sweep how to set 3 82 Relative RF frequency see frequency reference 3 45 RF frequency see frequency 3 39 RF frequency sweep see frequency sweep 3
124. BIG HOWDY FROM G0 and WELCOME TO SELF CAL G1 will appear on the display momentarily From now on the Back Space key when used during a data entry prompt will abort the Auto Adjust Routine ENTER ROUTINE NUM G8000 will prompt you to key in one of the routines from Table 5 3 If you have incorrectly entered data enter an extra digit and then you will be able to re enter the corrent data For example You wanted to enter 9 for the Routine Number but accidently pressed 8 Press any numeric key and INVALID DATA ENTRY G7002 will appear in the display Now you can re enter the 9 This approach will work with any Auto Adjust data entry Table 5 3 Auto Adjust Routine Numbers Module Routine Number A2 9 3 1 2 4 8 Adjustments Model 8642A B 9 When ENTER CURRENT MONTH G8001 appears key in a two digit number indicating the month Then press to continue 10 When ENTER TODAYS DATE G8002 appears key in a two digit number indicating the date Example For February 30 you would enter 30 Then press to continue 11 When ENTER CURRENT YEAR G8003 appears key in last two digits of the current year Example For February 30 1984 you would enter 84 Then press to continue 12 When ENTER MODULE CAL ID G8004 appears key in last five digits of the Module Cal ID number of the module you are running the Auto Adjust Routine for Then press to continue A2 EXAMPLE The Module Cal ID number
125. CTION 5 ADJUSTMENTS Adjustments tula s Gels ed Bend lee os SH E uud OR 0 Z aD ysi h ee 5 2 Auto Adjust Routines bu NO It Da Bee E dud 5 2 Description 9 2 2 4 3 2 aria DEAE RP ae vem RR BU dub qe siue dese ax 5 2 How All Auto Adjust Procedures 5 3 Correction Data Special Functions a oao caa e e a a e ee 5 5 Identifying the Contents of 20 5 5 Identifying the 5 7 Interpreting Cal Data Stats 5 8 viii rev 15 NOV90O Model 8642A B General Information Section 1 GENERAL INFORMATION 1 1 INTRODUCTION TO THE OPERATING AND SERVICE MANUAL This manual contains information required for a qualified person to install operate test adjust and service the Hewlett Packard Model 8642A B Signal Generator The HP 8642A B will generally be referred to as the Signal Generator throughout the manual The Operating and Service Manual is comprised of four volumes as described below Volume 1 Operation and Calibration Manual Product Note 8642A B 1 This Product Note explores the HP 8642A B features by discussing their benefits for your application Section 1 General Information General Information covers instrument specifications options equipment available recommended test equipment and an explana
126. Cal Data Stats later in this section for details about the display Table 5 5 HP 8642 Display for A20 Stats Module ID Number HP 8642 Display Service Special Function 0 Model Serial Options A11 Stats A12 Stats A6 Stats A13 Stats A19 Doubler Stats A16 or A19 Attenuator Stats A19 Rev Pwr Protect Stats A14 Stats A2 Stats 0 0 1 2 3 4 5 6 7 8 9 7 1f you wish to determine which data is the same between the A20 and the A3 key in Bz Some examples of the HP 8642 display are A20 with A19 exchange module before data down load A20 with 19 exchange module after data down load A20 with no data corresponding to the HP 8642 HP 8642 Cal Data Backup HP 8642B Cal Data Backup 5 6 Mode 8642A B Adjustments Identifying the Contents of the A3 The following is a procedure to display and identify the contents of the A3 Cal Data Memory 1 Key in to enter service mode 2 Key in to display the Module ID number of any Valid Cal Data in the A3 Board The A3 board EEPROM can be thought of as having 10 memory locations The address of each location numbered 0 through 9 is the Module ID Number Each memory location will either contain Valid Cal Data or it will be blank The A3 addresses that contain Valid Cal Data will now be displayed Some examples of the HP 8642 display are shown below Refer to Table 5 4 to cross reference the 3 addresses Module ID Numbers to the Memory Contents
127. DITIONAL HP IB INFORMATION 3 31 p quy pah h UR E 3 31 Trigger a acted niee doh Ea una s y aa sone Ps 3 31 Status Bite sss cite Pene m CEDE Cen 3 81 Controller Capabilities Self Test and Calibration 3 31 Display Control Via HP IB 3 31 Remote Indicators 3 31 Disabling the Listen Addressed State 3 31 Disabling the Talk Addressed State 3 31 HP IB CODES SUMMARY 3 32 Table 3 8 Signal Generator Function to HP IB Code 3 32 Table 3 9 Signal Generator HP IB Code to Function 3 33 HP IB RELATED FRONT PANEL KEYS 3 34 Figure 3 5 HP IB Related Front Panel Keys 3 34 HP IB RELATED TERMS 3 35 3 5 Model 8642A B Operation HP IB REMOTE OPERATION The 8642A B is fully programmable via the Hewlett Packard Interface Bus HP IB which can be operated with any Hewlett Packard computing controller or computer for automatic system applications For more information about HP IB refer to one or all of the following documents IEEE Standard 488 1978 ANSI Standard MC1 1 Improving Measurements in Engineering and Manufacturing HP part number 5952 0058 the Hewlett Packard catalog of Electronic Systems and Instruments or Tutorial Description of the Hewlett
128. Description Residuals are demodulated by the measuring receiver using either AM or FM mode FM Residual levels are measured in areas where the measuring receiver can resolve the measured performance of the HP 8642 under test in a 0 3 to 3 kHz Bandwidth If the HP 8642 has been repaired the Optional Residual FM Test Performance Test 14 should be performed in addition to this test Also if the Residual FM Test fails it will be necessary to run Performance Test 14 at the test points given here in Performance Test 4 to determine if the noise source is the measuring receiver LO or the HP 8642 sess sj GUT oo bon BB 83 o RECE VER SYNTHESIZED SIGNAL GENERATOR MODULE Figure 4 4 Residuals Test Setup Equipment Measuring Receiver s rusqa aguas eet edie les Fe eR Rn ry eer Ra REX EA dos HP 8902A Sensor Module r ree E EN RANA Wie Ried edu eate HP 11722A rev 08JUL88 Performance Test 4 4 13 Performance Tests Model 8642A B Procedure Setup 1 Connect the equipment as shown in Figure 4 4 2 Preset the instruments 3 On the measuring receiver enable the 300 Hz HP Filter and the 3 kHz LP Filter Residual AM 1 Put the measuring receiver in AM mode using the rms detector 2 Set the HP 8642 to the levels and frequencies in the following table and verify that the measuring receiver reading is less than the specified maximum HP 8642 1 HP 8642B only Residual FM 1 Put the measuring receiver in FM mod
129. E FM Special Function 112 This function selects the external ac coupled FM source for 0 4 Hz to 200 kHz rates and internal FM source summed together displaying the INT and EXT annunciators Refer to page 3 112 for more information about this special function e AC COUPLED DC FM Note AC Coupled DC FM is listed under DC Coupled Source on page 3 109 Model 8642A B Operation Modulation FM cont d DC Coupled Source When external dc coupled FM DC FM is selected the FM reference loop is no longer phase locked The applied signal is directly coupled to the FM VCO DC coupling also minimizes phase shift in the modulating voltage making dc coupled FM the preferred coupling path for maximum stereo separation Rate This function selects the external dc coupled FM source for dc to 200 kHz rates displaying the EXT and DC annunciators INT EXT DC EXT DC This function selects the external dc coupled FM source and internal FM source summed together displaying the INT EXT and DC annunciators AC COUPLED DC FM Special Function 118 This function causes the external signal to be applied to the unlocked FM VCO allowing maximum stereo separation characteristics displaying the EXT and DC annunciators Refer to page 3 116 for more information about this special function Determined by the external modulation source frequency NOTE External modulation frequency is not monitored by the Signal Generator The
130. E Ue sus apaku atum SIE E RR RR u usu telly HP 423B HPE eur bak tres huy aee e e E tdi e HP 11668A rev 08J UL88 Performance Test 13 4 41 Performance Tests 4 42 Model 8642A B 1 Connect the instruments as Setup B in Figure 4 13 Preset the instruments Insure that the detector is connected directly to the oscilloscope a Set up the oscilloscope as follows Channel A scale uuu sya Vo usu Da ONE YN NER iW det 1 00 volt div Channel B scale 10 0x10 volt div Channel A coupling ii guste tA iow ale he aA ate a aa an hee ae Yes DC Channel B co plihg s y Z re ade u pecu eee cae a a wi were Ta E dre iS DC Sweep Geste eee oe ce IRR OEE 41 1 0 us div Set up the function generator as follows T nctlon coder UC ere UTC p ue Ve Pulse Frequency vives veg UL oec e esce ee EAE ERR Kr e Ch VA nos 50 kHz Amplitude oe crow bent os Ro M En sere SMe ee hone 1 volt peak Amplitude Offset annern deens aria cee cee eee e essa ene 1 volt P lse Width sese tide ate 6 us Set up the spectrum analyzer as follows Center Frequency o oen eis E Ee ebrei vs e dies 1000 MHz Resolution BW Sa k oec rne pee ere dede toii e an ds 3 MHz Frequency Span e Ea EY EE a EE e T E 0 Hz Reference Level ccc cece ccc
131. ENCE You can use the Sequence function to select a particular sequence of instrument states saved in recall registers and then step through the sequence You can also view the next register to be displayed The Signal Generator has 51 registers 00 through 50 that can be recalled in sequential order The selected sequence is kept through Instrument Preset and through Power STBY to ON and unplugging of the ac power cord However if RAM memory is ever lost for example if the battery loses its charge the sequence will be lost and the default turn on sequence setting will be set as start OO stop 50 Note Put the instrument in its initialized state by selecting INSTR PRESET How to Select a Sequence SEQ Select the sequence range by first selecting the Set Sequence function and then by entering 2 two digit register numbers from 00 to 50 SET SEQ SEQ and the values for the desired range of recall registers When the Set Sequence function is selected the number of the next register is displayed as NEXT NN where NN is the two digit number of the next register to be recalled in the current sequence Only a sequence of increasing register numbers for example 10 through 20 can be selected How to Step Through the Sequence Just select SEQ J to step through the selected sequence Example Select a sequence from register 05 through register 15 First select SET SEQ program codes START S
132. ES 3 42 245 PHASE INCR 5 DEGREES 3 42 248 CAL MOD FREQ AGAIN 3 133 249 DISPLAY FIRMWARE INFO 3 176 250 PHASE ADJ KNOB UP DN 3 42 251 CLEAR RECALL REGS 3 159 Detailed list 3 176 Display current 3 169 3 212 Model 8642A B Special functions continued Select 3 168 Summary 3 170 3 171 Turn off 3 169 SRQ see also RQS 3 200 SRQ annunciator 3 207 START AMPTD 3 84 START FREQ 3 50 Step keys 3 149 Stereo separation 3 38 3 112 STOP AMPTD 3 84 STOP FREQ 3 50 Store see save or recall 3 159 SWEEP abbreviation 3 83 SWPNG annunciator 3 49 3 83 3 207 T TIME Amplitude 3 85 Frequency 3 52 TLK annunciator 3 207 U Units conversion 3 205 UR abbreviation 3 208 User messages writing to the display 3 201 UV abbreviation 3 208 V VL abbreviation 3 208 w Writing messages to the display 3 201 X X AXIS output 3 3 3 49 3 65 3 83 3 93 7 Z AXIS output 3 3 3 39 3 65 3 83 3 93 Mode 8642A B Performance Tests Section 4 PERFORMANCE TESTS 4 1 INTRODUCTION The procedures in this section test the instrument s electrical performance using the specifications from Table 1 1 as the performance standards All tests can be performed without access to the interior of the instrument Data points are given both for the 8642A and the 8642B when testing an 8642A delete the data points that apply only to the 8642B In general these are the specifications for RF frequencies gre
133. Errata Title amp Document Type 8642A B Synthesized Signal Generator Operation and Calibration Manual Manual Part Number 08642 90224 Revision Date 1996 03 01 HP References in this Manual This manual may contain references to HP or Hewlett Packard Please note that Hewlett Packard s former test and measurement semiconductor products and chemical analysis businesses are now part of Agilent Technologies We have made no changes to this manual copy The HP XXXX referred to in this document is now the Agilent XXXX For example model number HP8648A is now model number Agilent 8648A About this Manual We ve added this manual to the Agilent website in an effort to help you support your product This manual provides the best information we could find It may be incomplete or contain dated information and the scan quality may not be ideal If we find a better copy in the future we will add it to the Agilent website Support for Your Product Agilent no longer sells or supports this product You will find any other available product information on the Agilent Test amp Measurement website www tm agilent com Search for the model number of this product and the resulting product page will guide you to any available information Our service centers may be able to perform calibration if no repair parts are needed but no other support from Agilent is available Ae Agilent Technologies Errata Title amp Document Type 8642A B Sy
134. FT before entering data HP IB Don t send data immediately after selecting PL EM or KH NO ACTIVE FUNCTION E13 4013 Currently no function is active Select an active function and then try your setting again NOTHING TO BACKSPACE E14 4014 There is no data in the display to backspace Select an active function before using BACK SP J NO CURSOR TO MOVE E15 4015 Currently no function is active so no cursor can be moved Select an active function to activate the Knob before attempting to move cursors INVALID SHIFT FUNC E16 4016 The key you have selected cannot be preceded by the SHIFT key Select a valid shift function HP IB Select the proper function code without SH SH should only be used with the Display Output capability or to get back the normal display of instrument settings HP IB code SHSH Refer to Output Display information that begins on page 3 21 in the HP IB portion of this Section III INVALID TERMINATOR E17 4017 This message is never displayed locally HP IB Invalid terminator received Send correct terminator code for function you are trying to set 3 185 Operation Model 8642A B Operating Messages cont d BAD PREFIX RECEIVED E18 4018 bad prefix has been detected by the Signal Generator Terminator keys do not have shift functions HP IB The Signal Generator received a set of characters that cannot be recognized Send a valid HP IB code or use the HP IB Device Clear command and try again Refer
135. G for single Select the sweep time setting Select either the start or stop frequency setting Choose the frequency setting that is in the band that allows the desired FM or setting 8 Select the desired FM or deviation setting 9 Select either the stop or start frequency setting whichever of these which was not set in step 7 t gt Beo When entering data over HP IB the data entry can take the form of Implicit point notation for example 100 MZ or Fixed point notation for example 100 0 MZ or Exponential notation for example 1000E 1 MZ Each function has an HP IB data entry limit of 10 mantissa digits and 2 exponential digits exponential notation is optional For example the following entries for 100 MHz will be accepted 1000000000E 01 HZ 1000000000E 1 HZ 1000000000E 4 KZ However these entries for 100 MHz will not be accepted 10000000000E 02 HZ this entry will be accepted as 10 MHz 100000000E 006 MZ this entry won t be accepted and could cause problems in subsequent data entries Only the following data inputs are recognized over HP IB by the Signal Generator all other characters are 1gnored A Z a z lower case letters are converted to upper case 0 9 T Leading zeroes are treated as significant digits The space character carriage return and line feed are ignored rev 120CT87 Model 8642A B Operation lt gt DATA OUTPUT Overview The Signal Generator can send
136. HP IB in formation section Also reset with IP CS Device Clear Selected Device Clear Power On Bit 1 is cleared only if all hardware errors are resolved If that bit was causing SRQ to be pulled you must also read the Status Byte again to actually reset that bit This second reading will still show the error because the error is cleared only after the reading 3 30 Model 8642A B Operation x ADDITIONAL HP IB INFORMATION Abort Abort abruptly terminates all listener talker activity on the interface bus using the Interface Clear IFC bus line and prepares all instruments to receive a new command from the controller Typically this is an initialization command used to place the bus in a known starting condition The Signal Generator stops talking or listening when it receives the Abort message Trigger The Signal Generator does not respond to the Trigger message Status Bit The Signal Generator does not implement parallel poll operations and therefore cannot send a Status Bit message Controller Capabilities Self Test and Calibration The Signal Generator can be configured as a system controller to perform various self test and self calibration routines with a system voltmeter and the HP 8902A Measuring Receiver and an optional printer Refer to Section IV in the Service Manual for a detailed description of these routines Display Control Via HP IB Selecting the SHIFT key twice when in the local mode will
137. How Partial Preset Affects Instrument Settings u u VES E ne tem Ens 3 139 HP IB Codes 3 139 Comments su asas eee 3 139 KNOB oaa yas NS 3 141 2 tsi shad RAPERE 3 141 How to Control Knob Resolution Using the Cursor Positioning Keys 3 141 Operation INCR osi w ee ead 3 142 How to Control Knob Resolution by Setting Knob Increment 3 142 HOLD How to Use Knob Hold to Maintain Control of a Function s Value when Another Function Is Activ Sal puli Ne te Ses 3 143 HP IB Codes 3 144 Comments eee eh res 3 145 The Meaning of Multiple Cursors 3 145 STEP INCREMENT SET 3 149 INCR SET 2 Aur iude ea 3 149 How to Set Increment Size 3 149 rei CREE a NOD DOMUM 3 149 How to Increment a Function 3 149 How to Display the Increment Value 3 150 HP IB Codes 3 150 Comments 3 151 ENTRY OFF 3 153 Operation SETTING MODIFICATIONS w w v wow V V v V wow v COMI E CC C GS 2 9 C PARTIAL u INSTR Q OO rm OO 3 136 trument Preset enables you to set the Signal Genera r to an initialized
138. Hz 4 54 rev 08J UL88 Model 8642A B Performance Test Record Performance Test 5 AM FM and PM Tests cont d AM Distortion FREQ MHz 1 HP 8642A t NAE 2 HP 8642B t NAE PM Indicated Accuracy and Distortion CENE red 105 1 rad 105 1 rad DC FM Center Frequency Results 100 00000 9999950 99950 MHz 99 99950 MHz 100 00050 MHz reu 08J UL88 4 55 Performance Test Record Performance Test 5 AM FM and PM Tests cont d FM Indicated Accuracy Incidental AM FM Distortion 1 kHz 4 56 1 28 kHz 95 0 kHz 23 7 kHz 177 6 kHz 356 2 kHz 0 732 kHz 5 55 kHz 11 1 kHz 89 1 kHz 1 42 kHz 105 0 kHz 26 3 kHz 196 4 kHz 393 8 kHz 0 830 kHz 6 15 kHz 12 3 kHz 98 5 kHz Actual Distortion max 1050 72 0 256 135 0 4 67 5 Model 8642A B rev 08J UL88 Model 8642A B Performance Test Record Performance Test 6 Extended FM Distortion Test FM Distortion Measurement Actual Distn Max Performance Test 7 Internal Modulation Oscillator Tests Level Accuracy Frequency Accuracy rev 08JUL88 0 020 kHz 1 000 kHz 100 0 kHz 0 020 kHz 1 000 kHz 100 0 kHz MOD weas 20 0 Hz 14 9 kHz 15 1 kHz 100 0 kHz Performance Test Record Model 8642A B Performance Test 7 Internal Modulation Oscillator Tests cont d Distortion 0 020 kHz 15 80 kHz 100 0 kHz 0 020
139. IB This message may be output with OH or MG in combination with Output Display NO MESSAGE 00 0 No message 1s available for output over HP IB This message is never displayed locally HP IB This message may be output with OC or OE END OF MESSAGE LIST 00 0 The end of the copied Hhst has been reached This message is viewed after displaying the entire copied message list by repeatedly selecting the MSSG key HP IB This message may be output with OH or MG in combination with Output Display 3 181 Operation Model 8642A B Operating Messages cont d Parameters Changed Messages Local These messages are automatically displayed except for C32 and C33 HP IB of these messages can be output via HP IB using OC Parameters Changed messages message code is prefixed with inform you that the Signal Generator has changed some other setting to allow a new setting Some of the Signal Generator s functions cannot occur simultaneously with other functions so the Parameters Changed message indicates the Signal Generator has automatically adjusted or turned off the functions that are preventing the new setting These messages occur immediately after executing a command that causes some other parameter to automatically change HP IB You can read only the first Parameters Changed message if more than one has occurred For example assume that more than one Parameters Changed message has occurred since either the Sta
140. IB capability such as an HP 2225A The voltmeter must also have HP JB capability an HP 3478 HP 3455 or HP 3456 are some voltmeters that can be used A list of equipment needed for each Auto Adjust Routine is given in Table 5 1 At HP 8642 power up default HP IB addresses are assumed see Table 5 2 If the HP IB addresses of the external equipment are different from the default values use the service special functions given in Table 5 2 to re define the addresses the HP 8642 will use Table 5 1 Required Equipment for A uto A djust Module HP IB Printer HP IB DVM HP 8902A A2 No Yes or HP 8901A B Yes Yes or HP 8901A B Yes Yes Table 5 2 Changing the Default HP IB Addresses XX New two digit HP IB address Default Service Special Function Address Key Sequence Printer 01 81 XX Hz HP 8901A B HP 8902A 14 82 XX Hz DVM 23 83 XX Hz Model 8642A B Adjustments HP 8642 CONFIGURATION REQUIREMENTS FOR AUTO ADJUST To ensure proper operation and accuracy of Auto Adjust routines the HP 8642 must meet the following minimum configuration 1 Firmware Date Code must be 850620 or newer To determine the Firmware Date Code key in 9 The Firmware date Code is displayed in the format YYMMDD where YY is the last two digits of the year ie 85 MM is the number of the month ie 06 and DD is the day of the month ie 20 2 A2 Modulation Modules with Serial Prefixes 2714
141. Increment Set eee eA 3 149 Entry Ofir eo uncle ede uni Heu eu aere tur Ve ABA e ROS ed 3 153 Recall Registers sc s mea dos Dad QE ECL Sew E wed x ene du GER wher e cei edt dd 3 155 Recall Registers 3 155 Save Tecall uA kr s E eared Sau EO Si beu Dev su 3 157 Sequerice 27 vue dew esc ORDRE ISO E a gw be im ura Sd d beste e s doe aku 3 161 Special Functions _ 3 165 Special Functions 3 165 Special Functions z 22 5 vy eked g Si el ete eek ee ee 3 167 MESSAGES s ete Pr ete sva qp ra ya NC 3 177 Messages Contents ess 3 177 Operating Messages qonan niun a e a So SO eur CE dee G ath ka ta Rue do 3 179 Appendixes raises ot E mbi us B q L S Pa D dix Ned adir ne ate d 3 199 Apendix A Glossary sacos Lr ug oto eio Eum ee que a Eod dec ee d Rules dap p icu 3 199 Apendix B Writing Messages to the 3 201 Apendix C Amplitude Units Conversion 3 205 Apendix D Display Annunciators and 3 207 Appendix E Individual Instrument 3 208 1 SECTION 4 PERFORMANCE TESTS Introduction sa z ense trc uo ew de date dtd a dede ruina 4 1 Recommende
142. Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed Model 8642A B Description Procedures REL ZERO Operation RELATIVE RF FREQUENCY Relative Frequency mode enables you to display the output frequency relative to a reference frequency This function could be useful for example in setting a current frequency to be displayed as an offset from an IF frequency Settings for the relative frequency mode range from 2115 to 2115 MHz The Reference Set function sets the current display to read as an offset from a specific frequency reference The Reference Set function can also be used to display the current frequency reference The Relative Zero function sets the current frequency setting to be the frequency reference Once a frequency reference 1s selected all subsequent frequency entries are displayed as relative frequencies in terms of MHz above or below the frequency reference This condition exists until the Relative Frequency mode is turned off The output frequency is equal to the displayed frequency plus the reference frequency Note Put the instrument in its initialized state by selecting INSTR PRESET How to Set the Current Output Frequency Setting to Be the Frequency Referen
143. L 3 9 Modulation types not possible during 3 92 Relative settings 3 93 Step size 3 83 3 86 Zero span 3 92 Amplitude units conversion 3 205 Amplitude 3 69 Increment set values possible 3 73 Overranging 3 72 Resolution in dB 3 73 AMPTD OFF ON 3 72 AMPTD 3 70 AM 3 97 EXT AC EXT DC 3 98 INT 3 98 Maximum settings 3 102 Mixed modulation 3 101 Modulation restrictions with other functions 3 101 Rates increased using heterodyne band 3 101 Annunciators in the display 3 207 Arrow keys 3 141 ASCII character codes 3 203 AUTO sweep mode Amplitude 3 84 Frequency 3 51 B Basic operation 3 1 Battery power lost HP IB address 3 8 Recall registers 3 157 Sequence function 3 137 C Calibration messages 3 179 Converting amplitude units 3 201 3 205 Cursor positioning keys 3 141 Cursors multiple 3 145 D DB 3 208 DC see EXT DC 3 207 Detailed Operating Instructions 3 35 Display annunciators and abbreviations 3 207 Display flashing 3 1 Divide bands 3 38 3 199 DM 3 208 Index INDEX E 3 71 ENT ADRS 3 8 3 34 ENTRY OFF 3 143 3 153 Errors see messages 3 179 EXT AC AM 3 98 FM 3 108 M 3 121 Pulse Modulation 3 128 EXT DC AM 3 98 FM 3 108 M 3 121 Pulse Modulation 3 128 EXT REF INPUT 3 3 F Familiarization 3 1 Flashing display 3 1 INPUT 3 108 3 122 FM 3 105 Deviation limits affected by heterodyne band 3 105 Deviation limi
144. L bus command or the front pane LOCAL key The LOCAL key will not work if the instrument is in the Local Lockout State GTL RL1 Local Key is disabled during Loca Lockout so only LLO RL1 Require Service The Signal Generator sets the SRQ bus line true if one of the following conditions exists and it has been enabled by the RQS mask to send the message for that condition Parameter Changed Error Ready Local Remote Execution Error Hardware Error or End of Sweep Status Yes The Signal Generator responds to a Serial Poll Enable Byte SPE bus command by sending an 8 bit byte when addressed to talk Bit 6 RQS bit is true if Signal Generator had sent the Require Service Message Each bit requires different conditions for clearing Status Bit The Signal Generator does not respond to a parallel ATN poll Em ma T6 L3 The Signal Generator stops talking or listening Commands Control lines and Interface Functions are defined in IEEE Std 488 and the identical ANSI Standard s Knowledge of these might not be necessary if your controller s manual describes programming in terms of the twelve HP IB Messages shown in the left column Complete HP IB capability as defined in IEEE Std 488 and the identical ANSI Standard MC1 1 is SH1 AH1 T6 L3 LEO SR1 RL1 DC1 C1 C2 C3 C28 E2 3 10 Model 8642A B Operation Overview Program Cod
145. M memory could be lost for example if the battery loses its charge Refer to HP IB Address on page 3 8 If RAM memory has been lost the sequence function is set to a start register of 00 and a stop register of 50 3 137 Operation Model 8642 Instrument Preset Partial Preset cont d INSTR PRESET How Instrument Preset Affects Instrument Settings Selecting INSTR PRESET affects the instrument settings in the following ways 9 Re configures the instrument to the instrument preset configuration listed in Table 3 25 below 092927 9 Turns off special functions with code numbers less than 200 Disables Knob Increment and Knob Hold Sets the next Save Recall register number Clears any uncompleted HP IB messages Sets the HP IB RQS mask to nothing enabled to pull SRQ Clears the HP IB Status Byte except bits 3 Local Remote and 4 Ready unless there is an unresolved Hardware Error Selects RF frequency as the active function Table 3 25 Instrument Preset Configuration Initialized M Knob RF Frequency Start Frequency Stop Frequency Frequency Reference Amplitude Start Amplitude Stop Amplitude Amplitude Reference EMF Mode AM Depth FM Deviation Deviation Pulse Modulation Modulation Frequency Modulation Output Level Frequency Sweep Mode Amplitude Sweep Mode Sweep Time 100 0 MHz 10 MHz 1 MHz 100 0 MHz 10 MHz 1 MHz 100 1 MHz 10 MHz 1 MHz 100 0 MHz DNA DNA 140 0
146. MESSAGE CODES SUB Get message COM Gen addr Gen LET Byte SPOLL Gen IF BIT Byte 2 THEN CALL Execution IF BIT Byte 7 THEN CALL Change IF BIT Byte 1 THEN CALL Hardware ENABLE INTR 7 Execution Change Hardware SUBEND 1 SUB Execution OM Gen_addr Gen OUTPUT ENTER Gen Mssg code PRINT USING 460 Mssg code IMAGE EXECUTION ERROR CODE K ENTER Gen Mssg 1 74 PRINT Mssg 1 74 SUBEND SUB Change COM Gen addr Gen OUTPUT ENTER Gen Mssg code i PRINT USING 560 Mssg_code IMAGE CHANGE CODE K ENTER Gen Mssg 1 74 PRINT Mssg 1 74 RUBENS SUB Hardware COM Gen addr Gen OUTPUT ENTER Gen Mssg code IF Mssg code lt gt 0 THEN 690 ENTER Gen Mssg code PRINT NO HARDWARE MESSAGE FOUND GOTO 760 PRINT MESSAGE CODE Mssg_code ENTER Gen Mssg code IF Mssg code 0 THEN 690 ENTER 559 1 741 PRINT Mssg 1 74 IF Mssg 1 19 END OF MESSAGE LIST THEN 760 GOTO 720 SUBEND DEFINE 8642 ADDRESS COMMON AREA TO STORE GEN ADDRESS FOR SUB S DIMENSION SPACE TO ENTER IN MESSAGES READ STATUS BYTE CHECK MESSAGE BIT CHECK MESSAGE BIT CHECK MESSAGE BIT OUTPUT OE COMMAND READ MESSAGE CODE PRINT MESSAGE CODE READ MESSAGE PRINT MESSAGE OUTPUT OC COMMAND READ MESSAGE CODE PRINT MESSAGE CODE READ MESSAGE PRINT MESSAGE OUTPUT OH COMMAND READ MESSAGE CODE CHECK IF CODE 0 READ MESSAGE CODE PRINT
147. Messages to the Display cont d Messages The messages listed below might occur when you are accessing these special functions When using the instrument locally you will usually be able to view each message whenever it occurs When using the instrument via HP IB you can access some messages using the OE or OH commands Refer to Data Output page 3 15 in the HP IB portion of this Section III Messages accessed this way can be output in the form of a message code number or an actual alphanumeric message string In the following message listing the message code number that can be output over HP IB is provided to the far right of the message If no message code number is provided then that message can only be read over HP IB using Output Display unless otherwise stated which is also described in Data Output The messages that can be output using OE or can also be made to issue a service request Refer to Service Request page 3 27 in the HP IB portion of this Section III for information about service requests SPCL 3 ENTRY ERROR 12 This message occurs if the characters entered were not valid ENTER SERVICE CMD V16 This message occurs if the ASCII code entered was not recognized as valid MESSAGE 1 CLEARED V90 This message occurs when 6 J 593 C5 is selected MESSAGE 2 CLEARED V91 This message occurs when 6 C5 is selected MESSAGE 1 IS FULL 92 21092 This message might occur after attempting en
148. N This section provides the information needed to install the HP 8642A B Synthesized Signal Generator Included is information pertinent to initial inspection power requirements line voltage selection power cables interconnection environment instrument mounting storage and shipment 2 2 INITIAL INSPECTION WARNING To avoid hazardous electrical shock do not perform electrical tests when there are signs of shipping damage to any portion of the outer enclosure covers and panels Inspect the shipping container for damage If the shipping container or cushioning material is damaged it should be kept until the contents of the shipment have been checked for completeness and the instrument has been checked mechanically and electrically Procedures for checking electrical performance are given in Section IV Performance Tests If the contents are incomplete if there is mechanical damage or defect or if the instrument does not pass the electrical performance test 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 the Hewlett Packard office Keep the shipping materials for the carrier s inspection 2 3 PREPARATION FOR USE Power Requirements The Signal Generator requires a power source of 100 Vac 90 to 105 Vac 120 Vac 108 to 126 Vac 220 Vac 198 to 231 Vac or 240 Vac 216 to 252 Vac 47 5 to 440 Hz single phase Power
149. NO MESSAGES PRINT MESSAGE CODE READ MESSAGE CODE CHECK IF LAST READ MESSAGE PRINT MESSAGE LAST MESSAGE GO FOR NEXT MSGE 3 23 Operation Model 8642A B lt gt CLEAR Overview The Signal Generator responds identically to Selected Device Clear SDC and Device Clear DCL bus commands by clearing any message or uncompleted entries For example a command of FR100 would be cleared because no units terminator has been specified Also with the Clear command Clear Status Byte occurs possibly clearing up to 6 status bits The Clear command does not affect instrument settings However selecting Instrument Preset IP Partial Preset PP or turning the Power from Standby to On will reset instrument settings as described in the Detailed Operating Instruction Instrument Preset Partial Preset page 3 137 3 24 Model 8642A B Operation REMOTE LOCAL Local to Remote Transition The Signal Generator goes remote when it receives the Remote message The Remote message has two parts 1 Remote Enable bus control line REN set true 2 Device listen address received once while REN is true The Signal Generator s output signal and all control settings remain unchanged with the local to remote transition but any uncompleted messages non terminated partial entries are cleared LOCAL Remote to Local Transition The Local message is the way the controller sends the Go To Local GTL bus command The Signal Genera
150. NSTR PRESET J To select the Entry Off function ENTRY OFF CRF OFF ON To re enable the Knob and Step keys select a function to be active Disable the Knob Step keys etc to reduce the chance of inadvertantly altering the output signal while connecting output cables ENTRY OFF RF OFF ON program codes Display 3 idd addadBsBdnz FREQ AMPTD The absence of any cursor active function indication over the display settings indicates that settings cannot be changed with the Knob Step keys etc es Sos emm OFF 3 153 Model 8642A B Operation RECALL REGISTERS CONTENTS Figure 3 17 Functions Related to Recall Registers 3 156 SAVE RECALL e e 3 157 Table 3 27 Instrument Settings that Cannot Be Saved 3 157 SAVE uuu og Ur n AURI HC EM 3 157 How to Save an Instrument State 3 157 RECALL eit RUE Ae oi 3 159 How to Recall an Instrument State 3 159 HP IB Codes 3 159 Related Special Functions 3 159 251 Clear Recall Registers 3 159 SEQUENCE ieren kap aaa Yu 3 161 SET SEQ ed hee hin IS u Sisal Q 3 161 How to Select a Sequence 3 161 SEQ oec hri ENERO RENS ERN dd 3 161 How to Step Through the Sequence 3 161 HP IB Codes
151. Over second highest 10 dB of amplitude range X Axis Output 0 to 10 1096 Z Axis Output TTL positive true For crt display blanking during retrace An output amplitude sweep range of 30 dB is possible However the lowest 10 dB of amplitude range is not specified 2Buffer this output in order to use the Z axis output with a plotter for pen lift Procedures Note Put the instrument in an initialized state by selecting INSTR PRESET How to Turn On Amplitude Sweep Turn on amplitude sweep by selecting the amplitude sweep mode the sweep time and the start and stop amplitude values procedures for selecting these parameters are described in this instruction Upon selection of amplitude sweep the two sweep end points are displayed as the start amplitude and the stop amplitude These end points will be shown as AA OFF and AB OFF until sweep values are entered AA and AB are the HP IB codes for start amplitude and stop amplitude respectively Note that if the sweep mode has not been selected since the last time Instrument Preset has been selected auto sweep is automatically selected and causes the Signal Generator to begin sweeping immediately after end points are set The SWPNG annunciator indicates that a sweep is occurring 3 83 Operation Model 8642A B Amplitude Sweep cont d START AMPTD STOP AMPTD How to Set Start and Stop Amplitude Values 1 Set specific start and stop amplitude values Start Amplitude CSTAR
152. Packard Interface Bus HP part number 5952 01 56 All front panel functions are programmable over HP IB except Knob rotation and switching the Power from Standby to On Operation lt gt Model 8642A B HP iB ADDRESS The Signal Generator s address is set to 19 at the factory both in RAM memory and on an internal switch located inside the instrument You can change the address in RAM from the front panel The address stored in RAM remains valid through switching the Power from Standby to On and unplugging of the ac power cord However if the internal battery power is lost RAM memory is lost and the Signal Generator reads the address on the internal switch The internal switch address then becomes the address at turn on At any time the instrument s HP IB address can be displayed from the front panel Available Addresses To Display the Current Address ENT ADRS To Change the Address Comments Any address from 00 to 30 can be assigned to the instrument Setting an address of 31 establishes the Signal Generator as a listen only device The listen only mode causes the instrument to allow either HP IB or local operation However any keys pressed while the Signal Generator is receiving HP IB information could suspend the instrument in an unknown state Also with this address setting the HP IJB control lines should be left open circuited ATN REN SRQ and EO Refer to Figure 2 2 on page 2 7 for HP IB conne
153. Q and the value of the desired sweep start end point in GHz MHz kHz or Hz Stop Frequency STOP FREQ and the value of the desired sweep stop end point in GHz MHz kHz or Hz 2 You can also set last selected start and or stop frequency values by selecting COFF ON and or STOP FREQ J OFF HP IB codes FAON and FBON How to Stop the Sweep 1 You can stop the sweep by turning off both the start and stop end point settings CSTART FREQ OFF ON J STOP FREQ OFF ON HP IB codes FAOF FBOF When sweep 18 stopped the output frequency setting 1s equal to the end point value that was turned off last We recommend you exit frequency sweep this way to prevent Parameter Changed messages discussed on page 3 182 2 You can also stop the sweep by turning off just one of the end point settings when both end points are set for example CSTART FREQ OFF HP IB code FAOF When sweep is stopped the output frequency setting is equal to the remaining displayed end point value the value of the stop frequency We recommend you turn off frequency sweep this way when you want to set a function to occur during a frequency sweep for example AM Model 8642A B Operation RF Frequency Sweep cont d 3 During auto or single sweep in Stepped requency Sweep you can stop the sweep and display the actual output frequency by selecting manual sweep MANUAL SHFT STOP FREQ J Selecting either FREQ
154. REQ DISPLAY 0 6 HZ 146 RF FREQ DISPLAY 0 5 HZ 145 RFE FREQ DISPLA YY 0 4 HZ 144 RF FREQ DISPLAY 0 3 HZ 143 RF FREQ DISPLA Y 0 2 HZ 142 RF FREQ DISPLAY 0 1 HZ 141 RF FREQ DISPLA Y 0 1 HZ 151 RF FREQ DISPLA Y 0 2 HZ 152 RF FREQ DISPLA Y 0 3 HZ 153 RF FREQ DISPLA Y 0 4 HZ 154 RF FREQ DISPLA Y 0 5 HZ 155 RF EREQ DISPLA Y 0 6 HZ 156 RF FREQ DISPLAY 0 7 HZ 157 RF FREQ DISPLAY 0 8 HZ 158 RF FREQ DISPLAY 0 9 HZ 159 The current RF output frequency is now summed with one of these 0 1 Hz steps listed in messages 141 through 149 and 151 through 159 that were accessed with either Special Function 240 Decrement Frequency by 0 1 Hz or Special Function 241 Increment Frequency by 0 1 Hz The RF frequency addition is automatically deleted with any specific frequency setting or change These messages are queued up and can be displayed using MSSG HP IB Execute MG and read the display Perform this entire process repeatedly to see the RF frequency addition message Note that reading these messages over the bus using MG could cause transient hardware and service messages to be deleted from the message list refer to Queued Up Messages on page 3 180 CRUNCH CRUNCH MMMMMMM 160 Amplitude sweep is possible and is currently being set This message cannot be read via HP IB using Output Display because it automatically clears from the display after execution completes 3 195 Operation Model 8642 Operating Messages cont d Pr
155. START AMPTD J or STOP AMPTD J will also turn off the sweep but may cause a Parameter Changed message These messages are discussed on page 3 182 AUTO MANUAL SINGLE How to Select a Sweep Mode Sweep modes available are auto manual and single START FREQ or STOP FREQ must first be selected before of the frequency sweep modes can be selected Auto Sweep Auto sweep continually repeats the sweep sequence from start frequency to stop frequency AUTO SHET START AMPTD HP IB code FASA The SWPNG annunciator is continuously displayed During Stepped Frequency Sweep the auto sweep can be stopped to display the actual output frequency by selecting manual sweep In Stepped Frequency Sweep auto sweep mode does not allow the following settings Setting start and stop frequency end points if one end point is less than 4 130860 MHz Frequency Band 2 with a second end point greater than 132 187500 MHz Frequency Band 6 For more information about frequency bands refer to RF Frequency page 3 39 Setting a sweep across 1057 5 MHz 8642B only 9 Setting FM or M Manual Sweep Selecting manual sweep does not start a sweep but enables the Knob or the Step keys to control a frequency sweep MANUAL SHIT STOP FREQ HP IB code FASM Turn the Knob or select the Step keys to sweep between end points The actual output frequency as well as the SWPNG annunciator are displayed during the frequency sw
156. SU a 3 37 RE BrequenGy logged xd wed a kp wheres Bowes UE Quer Rue Rum ahh Eon ieu 3 39 Relative RF Frequency gua sua ee a 3 45 RF Frequency Sweep 3 49 Amplitude sx Ube G q xe Mp oe eus 3 67 Amplitude Contents esis oe d lll q sas ss Rmo h s 3 67 Amplitude x iu aid Ud vo do Sedo eur ruote esie e Neg bue seg ata 3 69 Relative Amplitude sla a La 24 45 4 gus S See E QR Se Ya d 3 77 Amplitude Sweep oic DSA ee eee eds es 3 83 S rev 15NOV90 Mode 8642A B Contents Modulation 5 EIL endi bu evt eie k LUPA SQ 3 95 Modulation Contents x xa Sai ea ou es 3 95 Modulation AM sce we a e moie ROS RR E A PSR eS 3 97 Modulation dolus LARS S Stan el bu cu ume ER x eie QUERN Eee s 3 105 Modulation s se ee sol ERI E RE SUA ee SES RU 3 119 Modulation Pulse ud ed WIRE Send top RUE RE e gens ae nk 3 127 Modulation Oscillator 3 131 Setting Modifications eee zehn 3 135 Setting Modifications 3 135 Instrument Preset Partial Preset 3 137 Knob Saa t Sup ade es 3 141 Step
157. Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III Display v m 77 FA FA rA TA TA TA FA FA m 7 2 5 eR ee c START FREQ SWPNG STO The display usually shows the start frequency and the stop frequency settings If another active function is selected the display could indicate frequency sweep with the SWPNG annunciator or by displaying FRQ SWEEPING in the left portiom of the display above the FREQ annunciator 3 56 Model 8642A B Operation RF Frequency Sweep cont d 4 Calculate a sweep time setting that could be selected for a desired step size 4a You need to choose the step size so the frequency span divided by the step size is an integer You must also ensure that the desired step size is between the maximum and minimum step size possible The maximum step size is equal to the maximum of 1 Hz Or Start Frequency in Hz Stop Frequency in Hz INTEGER OF ar Min Dwell Time in ms The minimum step size 15 equal to the maximum of 1 H or Start Frequency in Hz Stop Frequency 1023 4b When the sweep step size equals the minimum use a sweep time setting in ms equal to or greater than the result of the following calculation Start Frequency in Hz Stop Frequency in Hz 3 Y a i 1 X Min Dwell Time in ms Step Size in Hz When the sweep step size is greater than the minimum u
158. Special Function 249 In this example YYMMDD represents the numbers that will appear in the display where YY is the last two digits of the year MM is the number of the month and DD is the day of the month For example 570218 would be February 18 1957 KNOB INCR TURNED OFF 111 Knob increment mode was turned off Cursor positioning keys HP IB KL KR turn off the Knob Increment mode SETTINGS DISPLAY OFF 121 Special Function 135 Disable Display was selected and the display of the instrument settings is disabled Special Function 235 Re enable Display re enables the display of instrument settings PHASE STEP DOWN 1 DEG 122 PHASE STEP UP 1 DEG 123 The RF signals output phase was stepped down by 1 degree The RF signal s output phase was stepped up by 1 degree These messages are activated with Special Function 250 Refer to RF Frequency page 3 42 SPCL FUNC VERIFY OFF 124 Special Function 111 Special Function Verify Off was selected and the automatic Special Function verification is disabled A special function description will not be displayed automatically whenever a special function is selected The display of special function descriptions can be re enabled with Special Function 211 ENTERING SERVICE MODE 125 Entering the Service Mode Special Function 3 was just selected Either refer to page 3 201 for information about writing messages to the display or refer to the Service Manual or On Site Manual for information abou
159. Spurs That Occur with the Internal Source Internally generated spurs with specified levels less than 100 dBc might be present when the internal modulation oscillator is in use These spurs will be eliminated when no internal modulation source is modulating the carrier and the modulation oscillator output MOD OUT is off I Modulation Switching Time The time required to turn on the internal modulation oscillator or to switch between modulation frequencies can be reduced by approximately 200 ms the time depends on modulation frequency with a loss in modulation frequency accuracy by selecting Modulation Frequency Correction Off Special Function 113 For more intormation refer to Speeding Up Modulation Switching Time on page 3 132 Operation Model 8642A B Modulation Pulse cont d Related Special Functions Related Operating Instructions 3 130 Mixed Modulation The Signal Generator can simultaneously modulate the RF signal with more than one modulation type The Signal Generator does not allow simultaneous AM and pulse modulation or FM and Pulse modulation is allowed in the following combinations Either Internal pulse modulation or External dc coupled pulse modulation With any one of the following Internal FM External ac or dc coupled FM Internal external ac or dc coupled FM External low rate FM Special Function 5 Internal external low rate FM Special Function 112 Internal M
160. Sweep It is not possible to set an amplitude sweep directly in relative units Refer to page 3 205 for amplitude units conversion information to determine amplitude sweep start and stop end points in absolute units X AXIS A OV to 10V stepped output is available at the X AXIS output connector on the rear panel The amplitude points at the output coincide with the points in the sweep time calculations Z AXIS A blanking pulse is available at the Z AXIS output The blanking pulse is TTL positive true for CRT blanking during retrace There is a time that occurs between the end of the sweep and the beginning of the next sweep while the Z AXIS output is blanked and the frequency and X AXIS output are being reset This time is called start of sweep settling time Start of sweep settling time is not included in the sweep time setting Also start of sweep settling time 1s not selectable For amplitude sweep this settling time is approximately 15 of sweep time with a minimum of 7 ms and a maximum of 500 ms 121 Sweep Up and Down On During auto or single sweep modes the Signal Generator sweeps from the start end point to the stop end point and then sweeps from the stop end point to the start end point in the same amount of time See Figure 3 10 below for a comparison of the normal sweep mode Sweep Up and Down Off Special Function 221 and the up and down sweep mode Sweep Up and Down On Special Function 121 The waveforms are not drawn to
161. T AMPTD and the value of the desired sweep start end point in dBm V mV or uV If in the EMF mode the value can be set in EMF V EMF mV or uV Stop Amplitude and the value of the desired sweep stop end point in dBm V mV or uV If in the EMF mode the value can be set in EMF V EMF mV or uV 2 You can also set last selected start and or stop amplitude values by selecting COFF ON and STOP AMPTD OFF ON HP IB codes AAON and ABON To shorten the display of the message CRUNCH CRUNCH MMMMMMM 160 you can select either a faster sweep time or Special Function 122 Linear Amplitude Sweep while you are setting end point values How to Stop the Sweep 1 You can stop the sweep by turning off both the start and stop end point settings CSTART AMPTD OFF ON J STOP AMPTD LOFE ON HP IB codes AAOF ABOF When amplitude sweep is stopped output levels are reduced to the levels described in Table 3 14 RF OFF Output Amplitude Levels on page 3 72 We recommend you exit amplitude sweep this way to prevent Parameter Changed messages that are discussed on page 3 182 2 You can also stop the sweep by turning off just one of the end point settings for example COFF ON HP IB code AAOF When amplitude sweep is stopped the output amplitude setting is equal to the remaining displayed end point value Stopping the sweep using the above example would cause the output amplitude to to be equal to the value o
162. TOP 3 161 Operation Model 8642A B Sequence cont d HP IB Codes Comments After Set Sequence is selected the display shows the number of the next register to be recalled Note The display shown above may not match the display on your Signal Generator because this setting is saved through power down Now select the start register in the register range the display shows each number as it is entered Select 5 Display Now select the stop register in the register range Select 1 CS After all digits are entered the display returns to show its current instrument settings You can step through the sequence by pressing the SEQ key If no instrument states are saved in the registers you are sequencing through an error message will occur indicating that you ve recalled an undefined register HP IB Exactly 4 digits must always be used for setting the sequence Setting a Start Sequence Greater than the Stop Sequence If the start register number 15 greater than the stop register number the sequence will still increase and wrap around to 00 after 50 For example for a setting from 20 to 15 the registers recalled would be 20 21 22 etc to 50 then 00 01 etc to 15 Selecting a Random Order of Recall Registers It is not possible to select a random order of recall registers However because 51 registers are available a random order of some recall registers could be resaved in a sequent
163. TUDE tad odd one Not m ya c Det cars sed adea tee d 10 dBm ho MEE D paui EP 1050 MHz Set up the Signal Generator as follows AMPLETUDE d dos 18 dBm OG MED MEC 1050 025 MHz Adjust the Signal Generator level until it is equal to the HP 8642 level using the spectrum analyzer as the measuring device On the spectrum analyzer measure the signal at 1049 975 MHz relative to the signal at 1050 000 MHz Verify that it is below the required level given below Signal Generator Frequency Frequency MHz 1050 000 1050 025 me 50 dBc Performance Test 10 rev 08J UL88 Model 8642A B Performance Tests Performance Test 11 SSB PHASE NOISE TEST Specification Electrical Characteristics Residual SSB Phase Noise in 1 Hz Bandwidth Description Performance Limits 20 kHz Offset 200 kHz Offset 125 dBc 134 dBc band 10 134 dBc 143 dBc band 9 137 dBc 144 dBc band 8 141 dBc 144 dBc band 7 144 dBc 145 dBc band 6 145 dBc 145 dBc band 5 146 dBc 147 dBc band 4 147 dBc 148 dBc band 3 148 dBc 149 dBc band 2 137 dBc 138 dBc band 1 125 dBc 137 dBc band HET SSB phase noise is measured by mixing the RF output of the HP 8642 and its 10 MHz reference signal in a double balanced mixer to eliminate the carrier and translate the noise spectrum down to a low frequency where it can be viewed on a high resolu
164. age list that you can access The current message list always reflects the current state of messages However this list cannot be viewed directly Only a copied message list can be viewed You always copy the current list into the copied list to view the queued up messages At first reading this process may sound a bit confusing Read on for more confusion Some messages are transient and will be cleared from the current list when the condition they reflect no longer exists An example is RECALL ERROR FOUND H10 If for some reason you want to re display such transient messages or handle them via HP IB you could read the copied list since the current list would no longer contain that message To copy the current message list into the copied message list and view the first message Select MSSG HP IB MG when the message list is not already being scrolled through with the MSSG J key At this time all transient type messages will be deleted from the current message list Note This could also cause transient hardware and service messages to be deleted from the current message list To re read the copied message list and view the first message Select MSSG at any time to begin scrolling through the copied message list continue reading messages scroll through the copied message list Select MSSG repeatedly until the display of END OF MESSAGE LIST 00 Selecting CMSSG again brings back the
165. ally the Signal Generator changes the output in units of dBm with a maximum resolution of 0 1 dB Converting Amplitude Units Refer to Amplitude Units Conversion on page 3 205 for information about changing amplitude values from one unit to another Time Required for Output Level Switching Output level switching time is less than 100 ms from receipt of the last controller command Units Used for Increment Set Can Be Different Than Units Used for the Amplitude Setting An amplitude increment value can be set using a different unit specifier than the unit specifier displayed for example the amplitude increment could be in dB with an output setting in volts When dBm V mV uV or dBuV is selected the Signal Generator allows increment settings in dB V mV or uV When EMF V EMF mV EMF uV or dB EMF uV is selected the Signal Generator allows increment settings in dB EMF V EMF mV or EMF uV When the dBm and dBuV Keys Function as dBuV Terminators Both the dB key GHZ DBM and the dBuV key RAD function as dBuV terminators when the amplitude is set in dBuV All other relative amplitude settings use only the dB key as a dB terminator HP IB Either DB or DM When selecting units in dBm either HP IB code DM or DB can be used When selecting units in dB relative either HP IB code DB or DM can be used Therefore amplitude relative must be turned off APRF if you want DM to mean dBm HP 1IB Sequence Dependency Ampl
166. als Spurs That Occur with the Internal Source Internally generated spurs with levels specified less than 100 dBc might be present when the internal modulation oscillator is in use These spurs will be eliminated when no internal modulation source is modulating the carrier and the modulation oscillator output MOD OUT is off Modulation Output Phase The phase of the modulation output MOD OUTPUT is 180 out of phase with the internal use of the modulation oscillator Underranging Specified Modulation Oscillator Frequency Modulation oscillator frequencies as low as 10 Hz can be selected However the modulation oscillator s signal characteristics are not specified below 20 Hz Related Special Functions 113 Modulation Frequency Correction Off This special function disables the single band calibration of the modulation frequency oscillator that normally occurs whenever the modulation oscillator frequency is set or the internal modulation oscillator is put into use When this calibration is disabled the typical modulation frequency switching time is decreased by approximately 200 ms For more information refer Speeding Up Modulation Switching Time on page 3 132 213 Modulation Frequency Correction On This special function re enables the modulation frequency correction disabled with Special Function 113 248 Calibrate the Modulation Frequency Bands Again This special function enables you to initiate the calibration sequence that
167. also applies to RF frequency sweep Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed Model 8642A B Operation AMPLITUDE CONTENTS Figure 3 8 Amplitude Related Functions 3 68 AMPLITUDE e ass 8 69 Table 8 18 Output Amplitude Operating Characteristics 3 69 AMPTD eR ERE 3 70 How to Set the Amplitude Output with the Mode Off 3 70 RA ene ein Oe 3 71 How to Set the Amplitude Output in EMF Units iioii ed ei EE ME E ets 3 71 AMPTD OFF ON RF OFF ON 3 72 How to Turn Off the Amplitude Output 3 72 Table 3 14 RF OFF Output Amplitude Levels 3 72 HP IB Codes yur u ul aa m altu au LES 3 72 Comments Renee ana en 3 72 Related Special Functions 3 74 4 ALC Off enin 3 74 9 Attenuator Range Hold On 3 74 119 Disable Settling 3 74 Table 3 15 Attenuator Range Hold Amplitude and AM Ranges 3 75 Figure 3 9 Attenuator Range Hold Amplitude and AM Ranges 3 76 RELATIVE AMPLITUDE 3 77 REL ZERO oes
168. ange if 1t is also the active function or the active function will appear in the display and its value will change Model 8642A B Operation Knob cont d Three cursors in the display 1 A cursor above a digit and above the first letter of a units specifier and a cursor above the first letter of another units specifier h h ww TA gt mtr QuG6n unddunz SBBPE LA dv The placement of the two curse ove a function s setting display the P in this case indicates that Knob Hold control over that function the cursor over this function s value the 5 in th se indicates that turning the Knob will change the digit below the cursor single cursor above the other function s units specifier the V in this case licates it is the active function and as such that function s value will chage 1 you press the Step or Data keys or the Off On key if applicable M A cursor above each lette one units specifier and a cursor above the first letter of another units specifier The two cursors over the letters of a particular function s units specifier AM in this case indicate that both Knob Hold and Knob Increment are activated over that function When you turn the Knob that function s value will change by the Increment Set value The cursor over the other function s units specifier indicates it is the active function and as such its value will change when you press the Step or
169. anged from the front panel Refer to HP IB Address in the HP IB portion of Section 3 for information regarding changing the HP IB address HP IB Capabilities This Signal Generator s HP IB capabilities are defined by the following list of interface functions For more information refer to HP IB Capabilities in Section 3 Source Handshake SH1 Complete capability Acceptor Handshake AH1 Complete capability Talker T6 No talk only mode Extended Talker No capability Listener L3 Complete capability including Listen Only Extended Listener LEO No capability Service Request SR1 Complete capability Remote Local RL1 Complete capability Parallel Poll PPO No capability Device Clear DC1 Complete capability Device Trigger DTO No capability Controller C1 System controller C2 Send IFC and take charge C3 Send REN C28 Send interface messages Driver Electronics E2 Three state drivers 1 2 rev 30SEP88 Model 8642A B General Information 1 6 AN EXPLANATION OF THE ON SITE SERVICE STRATEGY The objectives of the on site service strategy are to provide the equipment and information necessary to enable service trained personnel to troubleshoot and repair the HP 8642A B to the module level at its operating site Using the On Site Service Kit refer to paragraph 1 12 for a description a service person should be able to successfully repair 80more of Signal Generator failures within two hours after arriving at the
170. anging End Point Values During the Sweep During auto or single sweep the Knob Step keys and Data keys can be used to change the start and stop end points and sweep time values During manual sweep the Knob and Step keys can only be used to perform the manual sweep HP IB How to Manually Sweep In manual sweep mode HP IB codes UP and DN can be used to step manually by one step each time the code is sent Knob rotation is not possible via HP IB How to Tell if the Start and Stop Frequency Entries Are Accepted If the frequency entries are accepted both values will appear in the display Jf the frequency entries are not accepted the displayed message will direct you to the entry error Sweep span width limitations for Phase Continuous Frequency Sweep Special Function 123 are listed in Table 3 12 RF Frequency Sweep Operating Characteristics page 3 49 or explained in How to Set Sweep Time that begins on page 3 60 For information about sweep span width limitations for Stepped Frequency Sweep refer to page 3 51 under How to Select a Sweep Mode Auto Sweep Modulation Types Not Possible During Frequency Sweep During Stepped Frequency Sweep FM and are allowed in manual or single sweep mode During Phase Continuous Sweep Special Function 123 all modulation types are allowed in all sweep modes However the sweep must be stopped to select modulation Model 8642A B Operation RF Frequency Sweep cont d DC FM with Pha
171. applied to the external FM M INPUT causes a positive frequency shift and a negative voltage applied causes a negative frequency shift 216 DC FM Correction On This special function re enables the correction disabled by Special Function 116 217 DC FM Update Mode Off This special function disables the DC FM update that occurs with Special Function 117 218 AC Coupled DC FM Off This special function re selects the dc coupling to the FM circuitry disabled with Special Function 118 219 Re enable Settling This special function re enables the settling disabled with Special Function 119 221 Sweep Up and Down Off This special function re enables the normal sweep disabled with Special Function 121 Special Function 221 sets the Signal Generator to repeatedly sweep from the start end point to the stop end point during auto or single sweep modes 222 Logarithmic Amplitude Sweep This special function selects the normally selected logarithmic stepped output disabled with Special Function 122 223 Phase Continuous Frequency Sweep Off This special function turns off the Phase Continuous Frequency Sweep selected with Special Function 123 Refer to RF Frequency Sweep page 3 49 234 Turn On LCD Lighting This special function turns on the LCD lighting disabled with Special Function 134 235 Re enable Display This special function re enables the display of settings disabled with Special Function 135 240 Decrement Frequency by 0
172. ase Noise at 1 GHz Carrier Frequency dBc 1 Hz bandwidth 40 75 98 j 131 138 146 7147 147 154 Measured SSB Phase Noise at 1 GHz SSB Phase dBc Hz SSB AM Noise Floor at 200 kHz Offset 16 dBm 157 dBc Hz band 2 through 9 150 dBc Hz band 10 MODULATION External Input Impedance 600 ohms 109 External Input Level Required 1 Vpeak for specified accu racy Front panel annunciators indicate application of 1V peak signal 596 20 Hz to 100 kHz When greater accuracy is required modulation drive voltage should be monitored externally Modulation Source Capability All modulation types can be driven with either an internal or external modulation source AM FM and can also be driven simultane ously by both internal and external modulation sources Mixed Modulation Types Any two modulation types can be simultaneously selected except for FM and AM pulse modulation FREQUENCY MODULATION Carrier Stability in FM Mode AC FM Same as CW DC FM 4 kHz hour 8642A B bands 1 9 HET 8 kHz hour 8642B band 10 FM Stereo Separation Ext dc Coupled HET Band Special Function 8 gt 50 dB 1 kHz rate 75 kHz deviation Low Distortion Special Function 5 or 112 Distortion in either FM or can be reduced with this function FM stereo separation unaffected FM Distortion in Special Function 7 lt 0 03 THD 1 15 maximum deviation external rates
173. ater than 1057 5 MHz unless otherwise noted NOTE If the performance tests are to be valid the following conditions must be met a The HP 8642 must have a 30 minute warmup b The mains line voltage must be within 5 10 of 100 110 220 or 240 volts rms AC at 47 5 440 Hz c The ambient temperature must be 0 to 55 degrees C d Before aging rate tests are performed the HP 8642 must have a 8 day warmup if it has been disconnected from the Mains power for more than 24 hours or if the HP 8642 has been disconnected from the Mains power for less than 24 hours it must have a 24 hour warmup 4 2 RECOMMENDED TEST EQUIPMENT Equipment required for the performance tests is listed in the Recommended Test Equipment table in Section 1 Any equipment that satisfies the critical specifications given in the table may be substituted for the recommended model s 4 3 TEST RECORD Results of the performance tests may be tabulated in the Test Record at the end of the procedures The Test Record lists all of the tested specifications and their acceptable limits The results recorded at incoming inspection can be used for comparison in periodic maintenance and troubleshooting and after repairs or adjustments 4 4 ABBREVIATED PERFORMANCE TESTING Limited Calibration Limited Calibration is a service offered by the Hewlett Packard Company Service Centers that involves on site performance testing of the HP 8642 Synthesized Signal Generator It is
174. ay is above that function s value For example if the cursor is over the RF frequency value you can enter a new frequency value or use the Knob or Step keys to change the value You do not need to press the FREQ key each time a change is desired active function prefix Many HP IB codes should not be entered without being prefixed by an active function code For a list of the active function codes and the codes that should be prefixed with an active function code refer to Table 3 8 Signal Generator Function to HP IB Code page 3 32 or Table 3 9 Signal Generator HP IB Code to Function page 3 3 3 alphanumeric The 8642A B has an alphanumeric display that is the display can show both alphabetic and numeric characters ASCII ASCII is an abreviation for American Standard Code for Information Interchange pronounced ask ee cursor The cursor is the triangular segment above an alphanumeric character in the display The cursor usually designates the active function and the resolution of the Knob Cursors also indicate the status of Knob Hold and Knob Increment Refer to Knob page 3 14 1 divide bands Divide bands are created when the Signal Generator s frequency range of 528 750001 to 1057 5 1s divided down to create its wide RF frequency range Refer RF Frequency page 3 39 function A function refers to each capability of the 8642A B Key functions are labeled directly on the key that accessed the function frequency
175. bands over the heterodyne band if possible This preference is disabled with Special Function 8 209 Attenuator Range Hold Off This special function turns off Attenuator Range Hold selected with Special Function 9 211 Special Function Verify On This special function re enables the automatic display of the special function description disabled with Special Function 11 1 212 Internal External Low Rate FM Off This special function turns off the FM modulation source selected with Special Function 112 When Special Function 112 is turned off this way the Signal Generator selects internal and external ac coupled FM summed together 213 Modulation Frequency Correction On This special function re enables the single band calibration that normally occurs whenever the modulation oscillator frequency is set or the internal modulation oscillator is put into use Refer to page 3 173 Special Function 113 3 174 Model 8642A B Operation Special Functions cont d DETAILED DESCRIPTIONS OF ALL SPECIAL FUNCTIONS cont d 214 Positive M Polarity This special function disables Special Function 114 and re enables the normally selected phase relationships A positive voltage applied to the external FM M INPUT causes a phase lead and a negative voltage applied causes a phase lag 215 Positive FM Polarity This special function disables Special Function 115 and re enables the normally selected frequency shift relationships A positive voltage
176. binations of these functions Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III Table 3 20 Maximum FM Deviation Settings with only an External Source Maximum FM Deviation Settings kHz per Volt Frequency Range MHz n EST Pre Emphasis On Special Function 6 1057 500001 to 2115 00000 3000 000 420 498 8642B only 528 750001 to 1057 500000 1500 000 210 249 264 375001 to 528 750000 750 000 105 124 132 187501 264 375000 375 000 52 562 66 093751 to 132 187500 187 500 26 281 33 046876 to 66 093750 93 750 13 140 16 523438 to 33 046875 46 875 6 570 8 261719 to 16 523437 23 437 3 285 4 130860 to 8 261718 11 718 1 642 0 100000 to 4 130859 93 750 13 140 0 100000 to 132 187500 1500 000 210 249 9 8 7 6 5 4 3 2 1 m2 When FM deviations exceed limits listed for Bands 1 through 6 the Signal Generator automatically switches to the Heterodyne Band Related Special Functions 5 External Low Rate FM On 112 Internal External Low Rate FM On These special functions typically provide 0 4 Hz to 200 kHz external FM ac coupling with the Signal Generator remaining in a phase locked state Input coupling required for these functions makes the Signal Generator especially sensitive to dc voltage fluctuations Relatively small dc voltage changes can cause the Signal Generator to lose phase lock requiring one to two seconds to regain the locked condition These f
177. ce Setting the current output frequency as the frequency reference causes the frequency setting display to become 0 000000 MHz relative FREQ REL ZERO CSHET CAMPTD Example Configure the front panel display to read each subsequent frequency relative to a current frequency of 500 MHz First select INSTR PRESET J and set the RF frequency to 500 MHz then perform the following steps wm mm LOCAL keys REL ZERO FREQ SHIFT program FRRZ codes Operation Model 8642A B Relative RF Frequency cont d Display 3 r4 v FA PA e S ed A K li FREQ REL AMPTD I FA Ti TYR Zn The FREQ REL annunciators indicate that the requency display is relative All subsequent frequency settings will be entered and displayed as MHz relative to the frequency reference of 500 MHz The absolute output frequency is the displayed frequency plus the frequency reference REF SET How to Set a Reference to a Specific Frequency Setting a specific RF frequency as the frequency reference causes subsequent frequency settings to display the current output frequency as MHz relative to the frequency reference CFREQ REF SET CSHFT CAMPTD and the value of the desired reference frequency in GHz MHz kHz or Hz Example With a current RF frequency output of 100 MHz configure the front panel to allow entry and display of all frequency setting values as an offset from a 1
178. cification Electrical Characteristics Performance Limits 1 x 107 day Aging Rate Option 001 only After eight day warm up typically 24 hrs in normal operating environment Description The reference signal from the HP 8642 10 MHz OUTPUT is connected to the oscilloscope s vertical input A frequency standard with long term stability greater than 1 x 10719 is connected to the trigger input The time required for a specific phase change is measured immediately and after a period of time The aging rate is inversely proportional to the absolute value of the difference in the measured times 10 MH2 OO ano BB HP 8642A B VERT ICAL SYNTHESIZED SIGNAL GENERATOR Figure 4 15 Internal Time Base Aging Rate Test Setup Equipment Frequency Standard A ERE esee A enne HP 5065A Oscilloscope sauce ure tee e Yr e we celia t Raa eia reu ern eS HP 1740A rev 08J UL88 Performance Test 15 4 45 Performance Tests Model 8642A B NOTE Be sure the HP 8642 has had 10 days to warm up before beginning the test If the HP 8642 was disconnected from the power line for less than 24 hours only a 24 hour warm up is needed Procedure 1 Set the rear panel REFERENCE switch to INT Connect the instruments shown in Figure 4 15 Adjust the oscilloscope s controls for a stable display of the 10 MHz output gt 0 N Measure the time required for a phase change of 360 degrees Record t
179. cm away from any surface for output levels lt 0 dBm 32 7 kg 71 5 Ib 43 kg 95 Ib 133 mm 5 25 in nominal 425 mm 16 75 in nominal 617 mm 23 8 in nominal Sweeps between two selected end points in a linear step wise manner End points can be anywhere within the frequency range of the instrument In AUTO sweep mode sweep must stay within the range of bands 2 through 9 or band 1 or band 10 or the HET band Maximum sweep time 999s Minimum sweep time 275 ms A maximum number of distinct frequency points is automatically selected based on the end points and sweep time instrument sweeps between two selected end points in a linear phase continuous manner End points can be outside the band but Start Frequency Stop Frequency 2 must be within the band 800 kHz 400 kHz 200 kHz 100 kHz 50 kHz 25 kHz 12 5 kHz 6 25 kHz 3 125 kHz 25 kHz 400 kHz 9Maximum sweep span may be increased up to that shown for the HET band 0 1 MHz to 132 1875 MHz carrier frequency by selecting a frequency span larger than the span shown here HET band can also be selected with Special Function 8 General Information Model 8642A B Table 1 1 Specifications 6 of 6 FREQUENCY SWEEP Cont d Phase Continuous Sweep Cont d Sweep Time X Axis Output Z Axis Output REMOTE OPERATIONS HP IB IEEE 488 1978 Capability Interface Functions Controlled HP IB Address Select Code Interface Function IEEE 488 Func
180. cs Electrical Performance Characteristics Limits M Deviation Limitations Accuracy Resolution Distortion M 3 dB Bandwidth See Figure 3 15 5 of setting 0 09 radians 1 kHz rate 0 7 of setting or 0 0004 of maximum deviation whichever is larger 0 496 20 Hz to 15 kHz dc to 15 kHz 1 kHz rate Internal and external ac External dc 3 119 Operation Model 8642A B Modulation cont d Procedures INT 100 50 MAX I MUM M DEVIATION 42 5 Radians INT 6 25 Radians per volt EXT 3 125 1 5625 0 78125 RF FREQUENCY MHz Actual band boundaries are listed in Table 3 11 8642B ONLY Figure 3 15 4M Deviation Limitations for each RF Frequency Band You can determine whether the Signal Generator will select a divide band or the heterodyne band Assume an RF frequency of 30 MHz if you select a deviation of 3 radians the Signal Generator will use divide band 4 since the maximum possible deviation for band 4 is 3 125 radians unless Special Function 8 Prefer Heterodyne Band is selected If you select a deviation of 25 radians the Signal Generator will automatically select the heterodyne band Note that the maximum possible deviation for the heterodyne band is 100 radians Note Put the instrument in its initialized state by selecting INSTR PRESET M can be configured to use either the Signal Generator s internal modulation oscillator an external source or
181. ctor pin numbers for these lines From the front panel select ENT ADRS SHET LOCAL J From the front panel select ENT ADRS SHIFT LOCAL followed by a data entry from 00 to 31 and HZ UV or any terminator The Signal Generator s internal switch address can also be changed using a procedure described in Section VIII of the Service Manual in Service Sheet 2 However this address will only be used when Power is turned from Standby to On if the internal battery power is lost WARNING The setting of the switch that is described in Section VIII is intended for service trained persons who are aware of the potential shock hazard of working on an instrument with protective covers removed System Control Setting the address from the front panel when the instrument is in its service mode will disable any activated HP IB control capabilities Refer to the Service Manual for more information about configuring the Signal Generator as a system controller to perform various self test and self calibration routines Model 8642A B Operation lt gt HP IB CAPABILITIES Ovei view The 8642A B Signal Generator is designed to be compatible with a controller that interfaces in terms of the 12 bus messages summarized in the HP IB Capability Reference Table on page 3 10 The bus functions are discussed in more detail in the following text The Signal Generator s complete capability as defined by IEEE Standard 488 and the
182. cy Sweep In other words if your settings are not possible in a divide band but are possible in the Het band at the identical RF frequency the Signal Generator will sometimes automatically switch to the Het band to allow your settings However selecting Special Function 8 Prefer Heterodyne Band forces the Signal Generator to always operate in the Het band whenever RF frequency is less than 132 187501 MHz regardless of FM or deviation or Phase Continuous Frequency Sweep span limits This special function prevents the Signal Generator from switching to the divide bands from the Het band when the settings would allow operation in the divide bands Refer to Figures 3 12 and 3 13 page 3 106 for the FM deviation limits in each frequency band Refer to Modulation page 3 119 for the deviation limits in each frequency band Refer to RF Frequency Sweep page 3 49 and 3 60 for information about frequency span limitations in Phase Continuous Frequency Sweep Note Put the instrument in its initialized state by selecting INSTR PRESET J How To Set RF Frequency 3 40 RF frequency is set by selecting the RF frequency function and then entering the desired frequency FREQ and the value of the desired RF frequency up to 10 digits in GHz MHz kHz or Hz Example Set RF frequency to 1 23 MHz ENTRY DATA LOCAL program codes Model 8642A B Operation RF Frequency cont d Display i
183. cy is typically 3 dB 28642B Band 10 Procedures Note Put the instrument in its initialized state by selecting INSTR PRESET INT How to Set Pulse Modulation with the Internal Source Using the Modulation Oscillator Source PULSE CAM CNT Rate MOD FREQ and the desired value of modulation frequency in kHz or Hz Pulse Modulation PULSE CAM and OFF ON rev 20MAR85 3 127 Operation Model 8642A B Modulation Pulse cont d Example Pulse modulate the RF output using the internal modulation oscillator at a 2 kHz rate starting with pulse modulation off MODULATION SOURCE ENTRY DATA LOCAL keys s m E PLNT MF 2 KZ PLON ENTRY PULSE OFF SHIFT Display The RF output is being internally pulse modulated as indicated by the word PULSE and the annunciator INT Modulation frequency is set to 2 kHz The duty cycle is 50 The cursor above the pulse modulation display indicates that pulse modulation can be toggled off and on by selecting the OFE ON key Note that the AM annunciator is displayed if the word PULSE can t be displayed EXT DC How to Set Pulse Modulation with an External Source Do not apply more than 15 Vpk to the AM PULSE INPUT or damage to the Signal Generator s circuitry could result Source Connect the external modulation source to the AM PULSE INPUT connector input impedance of 600 ohms and select PULSE
184. d END OF MESSAGE LIST 00 you know there are no more messages in that list When Controlling the Instrument via HP IB You can access most of the messages using the OC OE and OH commands Refer to the discussion about Output Messages which begins on page 3 16 in the HP IB portion of this Section IIL Messages accessed this way can be output in the form of a message code number or as an actual alphanumeric message string In the message listing in this instruction the message code number that can be output over HP IB is provided to the far right of the message If no message code number is provided in the listing then that message can be read over HP IB using Output Display unless otherwise stated which is described in on page 3 21 If any unique message retrieval prodedures exist for a message they will be described in the individual message description Also any message that cannot be read via HP IB will be noted Many of the messages that can be output over HP IB can be made to initiate a service request For more information about service requests refer to Service Request on page 3 27 in the HP IB portion of this Section III Operation Model 8642A B Operating Messages cont d HP IB Codes Comments 3 180 es Queued Up Messages The instrument 15 constantly checking its status and updating its current message list appropriately However the current message list is different from the copied mess
185. d Test Equipment 2 2 2 aa a e 4 1 Abbreviated Performance Testing 4 1 Level Accuracy and Flatness Tests 2 4 3 Harmonics Tests So eels pu aw E S Q ea ae Dae ee eee aU E 4 9 Pulse On Off Ratio Test 5 24559 Og ee UE lw uo Se Eee SUQ Q s 4 11 Residuals Tests Aw eis Kh Bee ble eco HOUR be Pee Mees ated 4 13 AM FM and OM Tests 9 oon thw gece ec deett e weder toO E weite a b ei de RI T 4 15 Extended FM Distortion Test a a r e e s a ls es 4 22 Internal Modulation Oscillator Tests 22 2222 a sss 4 24 ke d ci M e Er Cc c d A attest aeu ak wa Me Bhat ae Paus efc Ia 4 27 Spurious T st aM ed sh uet aie sU rate M 4 31 Third Order 2 e sss 4 33 SSB Phase Noise amp 4 35 SSB Phase Noise Test Optional 2 222222 ll s s ls Rss 4 38 Extended Pulse Tests Gee ER eS Row D ee ah pare AS MES Sud 4 41 Optional Residual FM Test 222222 a o Re 4 48 Internal Time Base Aging Rate Test 0 22222 les 4 45 Pest Recordi at E awa Palu ana Es Pa uQ Bp a a ees AU rd eB 4 49 rev LONOVIO vil Contents Model 8642 SE
186. d for Phase Continuous Frequency Sweep in Table 3 12 page 3 49 will not necessarily be possible unless sweep time is set within limits that will allow that sweep span This same restriction holds true when setting sweep time that 15 the sweep time set ngs listed in Table 3 16 will not necessarily be possible unless sweep span is set within limits that will allow that sweep time The calculations for this second part allow you to determine the minimum sweep span for a desired sweep time and frequency band 2 the maximum sweep span for a desired sweep time and frequency band 3 the minimum sweep time for a desired sweep span and frequency band 4 the maximum sweep time for a desired sweep span and frequency band 5 the number of automatically selected X axis steps based on a sweep time setting and 6 the required sweep time to select a specific number of X axis steps 3 52 Model 8642A B Operation RF Frequency Sweep cont d How to Set Sweep Time for Stepped Frequency Sweep Using Sweep Time to Set Frequency Step Size and Number of Steps The operating characteristics for sweep time are as follows Minimum Sweep Time 275 ms Maximum Sweep Time 999s Sweep Time Resolution 1 ms Minimum Frequency Sweep Step Size 1 Hz Minimum Frequency Dwell Time Per Point Settling Status 8642A 8642B Special Function 119 60 ms 80 ms Disable Settling Special Function 219 110 ms 135 ms Re enable Settling Stepped Frequency Swee
187. d state by selecting INSTR PRESET AM can be configured to use either the Signal Generator s internal modulation oscillator an external source or combinations of the two sources rev 20MAR 85 3 97 Operation Model 8642A B Modulation AM cont d INT How to Set AM with the Internal Source Using the Modulation Oscillator Source CAM CNT Rate MOD FREQ and the desired modulation frequency in kHz or Hz Depth and the desired modulation depth in Example Amplitude modulate the RF output using the internal modulation oscillator 80 AM depth at a 12 kHz rate MODULATION SOURCE MOD kHz rad 8 Co program AMNT MF 12 KZ AM 80 PC codes Display The RF output is being internally amplitude modulated as indicated by the AM and INT annunciators AM depth is 80 04 Modulation frequency is set to 12 00 kHz The cursor above the AM setting indicates that AM is the active function EXT AC EXT DC How to Set AM with an External Source Source Do not apply more than 15 Vpk maximum external voltage to the AM PULSE INPUT or damage to the Signal Generator s circuitry could result The external modulation source connects to the AM PULSE INPUT connector input impedance of 600 ohms 3 98 rev 20MAR 85 Model 8642A B Operation Modulation AM cont d The external modulation signal level should be adjusted to a i Vpk 0 707 Vrms sinewave input to the Signal Generator to get the displa
188. dBm 1 dB 0 1 dB 140 0 dBm 1 dB 0 1 dB 135 0 dBm 1 dB 0 1 dB 1 00 nV DNA DNA DNA DNA DNA 5096 Internal Source 1096 0 196 50 0 kHz Internal Source 5 0 kHz 0 1 kHz 1 0 radians Internal Source 0 1 radians 0 01 radians External DC Source DNA DNA 1 000 kHz 1 000 kHz 0 001 kHz 1 00V 0 1V 0 01V Auto DNA Auto DNA 500 ms DNA Does Not Apply 3 138 Mode 8642A B Operation Instrument Preset Partial Preset cont d PARTIAL How Partial Preset Affects Instrument Settings Selecting PARTIAL SHEET J INSTR PRESET affects settings as follows Partial Preset does not change the setting of RF Frequency Amplitude Reference EMF Mode Sweep Mode Auto Manual or Single selection HP IB Status Byte HP IB RQS Mask Partial Preset turns off the following functions but maintains their last selected values as on settings that can be selected with the OFF ON key AM Depth FM Deviation M Deviation Pulse Modulation Modulation Output Level Start Frequency Stop Frequency Start Amplitude Stop Amplitude Frequency Reference Partial Preset sets the following functions to the initialized states and values listed in Table 3 25 on the previous page Modulation Frequency Sweep Time Partial Preset also Maintains the next Save Recall register Disables Knob Hold and Knob Increment Maintains all Increment Set values and Knob cursor positions Turns off all special functions with code n
189. desired output level CAMPTD and the desired output level in dBm V mV uV or dBuV the RAD key 1s the dBuV terminator Example Set the RF output to 107 3 dBm DATA LOCAL keys J C3 09 En C3 63 GE program AP 107 3 DM codes Display e Ld d d d e 2 d d im Amplitude has been set to 107 3 dBm The cursor above the amplitude display setting indicates amplitude is the active function Example Set the RF output to 6 dBuV program codes Display Anu FA rA FA iTi 7 1 IOO U III 2 H FREQ AMPTD REL Amplitude has been set to 6 0 dBuV The AMPTD REL annunciators indicate that dBuV is a relative setting Even though dBuV can be set directly from the front panel the way this function operates and the way it is displayed are similar to most relative settings Refer to Relative Amplitude page 3 77 3 70 rev 20MAR 85 Model 8642A B Operation Amplitude cont d EMF How to Set the Amplitude Output in EMF Units The EMF mode 1s turned on using these selections EMF CSHIET INCR SET ON HP IB code EMON Then the EMF amplitude output can be set by selecting the amplitude function and setting the desired output level and the desired output level in V mV uV or dBuV the BAD 95 key is the dBuV terminator Subsequent voltage entries will be in EMF units note the EMF annunciator until the EMF mode is turned off You can turn off the EMF m
190. diately after end points are set The SWPNG annunciator indicates that a sweep is occurring If Stepped Frequency Sweep is desired but Phase Continuous Frequency Sweep Special Function 123 is on Phase Continuous Frequency Sweep Off Special Function 223 must be selected However before Special Function 223 can be selected one of the start or stop frequencies must be turned off using a procedure from How to Stop the Sweep below How to Select Phase Continuous Frequency Sweep Special Function 123 Phase Continuous Frequency Sweep 1s turned on by first selecting Special Function 123 then by selecting the sweep mode auto manual or single sweep time and start and stop frequencies procedures for selecting these parameters are described below Note that if the sweep mode has not been selected since the last time Instrument Preset has been selected auto sweep is automatically selected and causes the Signal Generator to begin sweeping immediately after end points are set The SWPNG annunciator indicates that a sweep is occurring If Phase Continuous Frequency Sweep is desired but Stepped Frequency Sweep is on one of the start or stop frequencies must be turned off using a procedure from How to Stop the Sweep below before Phase Continuous Frequency Sweep Special Function 123 can be selected START FREQ STOP FREQ How to Set Start and Stop Frequencies 1 Set specific start and stop frequency values Start Frequency CSTART FRE
191. display the instrument settings last selected In the remote mode you can send SHSH to achieve this same effect This may be useful when outputting display information Remote Indicators The Signal Generator displays HP IB annunciators to indicate its current HP IB status RMT When remote operation is selected LSTN When addressed to listen TLK When addressed to talk SRQ When pulling the SRQ line with the RQS bit set in the Status Byte Disabling the Listen Addressed State The Signal Generator remains addressed to listen until It 1s addressed to talk It receives an abort message It receives a universal unlisten command or Until the Power is switched from Standby to On Disabling the Talk Addressed State The Signal Generator remains addressed to talk until It is addressed to listen It receives an abort message It receives some other device s talk aadress It receives a universal untalk command or Until the Power is switched from Standby to On 3 31 Operation Frequency Frequency Start Frequency Sweep Stop Frequency Sweep Amplitude Amplitude Start Amplitude Sweep Stop Amplitude Sweep EMF Mode Modulation AM Depth FM Deviation M Deviation Pulse Modulation Oscillator Modulation Frequency Modulation Output Level Modulation Source Internal External AC External DC Internal External AC Internal External DC Data Numerals 0 9 Decimal point Back Space Units lActive func
192. e INT EXT and DC annunciators Rate Determined by the external modulation source frequency NOTE External modulation frequency is not monitored by the Signal senerator The Signal Generator s modulation frequency display refers to the internal modulation oscillator only Deviation CSHFT EM and the desired value of deviation in radians per volt When using an external source the M deviation setting does not set the actual deviation it sets the input sensitivity per volt A linear relationship exists between the deviation setting and the external voltage applied for voltages less than approximately 1 2 Vpk NOTE With simultaneous internal and external modulation the sum of the internal and external signals should not cause the M deviation to exceed the limits mentioned on page 3 119 If these limits are exceeded the Signal Generator could go out of lock which causes queued up Hardware Error messages Also the external FM M INPUT does not respond linearly to inputs greater than approximately 1 Vpk 3 122 Model 8642A B Operation Modulation cont d Example Phase modulate the RF output with an external 1 Vpk dc coupled source 2 radians deviation at a rate determined by the external source s frequency ENTRY MODULATION SOURCE SIT ENTRY DATA LOCAL keys sw se s Me PMXD PM 2 RD codes These codes are not independent and might need to follow a
193. e LA MC se beak atc 1 Hz SWEEP TIME ie Z aaa gua LE E E a rN OSIA EWEIN 5 0 sec ATTENUATION niteen cab nuk ders ooi a ae iei 0 dB RESOLUTION Sene A ihe 10 Hz CENTER si aena a Qa wS ayay ra NaS forr SITO ERA Syn A wee 0 Hz REFERENCE LEVEL isnot t bas enon 50 dBm 4 Record the level of the peak signal for later use dBm NOTE It may be necessary to fine tune the spectrum analyzer center frequency adjustment The spectrum analyzer band width will be centered when the maximum signal level is obtained while tuning the center frequency adjustment 5 Set the HP 8642 to fkr then 0 dBm amplitude by incrementing the amplitude in 10 dB steps CAUTION Use the oscilloscope to verify that no large AC signal is present If AC is present the mixer input signals are not at the same frequency and spectrum analyzer damage may result rev 08JUL88 Performance Test 12 4 39 Performance Tests Model 8642A B 6 On the HP 8642 enter SPCL 250 View the signal in the dc coupled mode on the oscilloscope Use the HP 8642 knob to adjust the dc level on the oscilloscope as close to zero as possible This sets the two input signals to the mixer in phase quadrature 90 degrees out of phase 7 View the trace and note the average noise level 8 The actual phase noise is calculated from the reading obtained in step 6 by applying the following correc
194. e Recovery Example Program on page 3 23 provides some sample subprograms that detail a way to retrieve the Signal Generator s messages Execution Errors and Parameters Changed Messages After it receives OE or OC and is addressed to talk the first time the Signal Generator will output the message code number The second time it is addressed to talk the Signal Generator will output the message string You can read only the first Execution Error message if more than one of these has occurred since either the Status Byte was cleared or since the last time OE was executed Then reading a message using OE will enable you to read out only the first Execution Error message Model 8642A B Operation You can read only the first Parameters Changed message if more than one of each of these has occurred since either the Status Byte was cleared or since the last time OC was executed Then reading a message using OC wil enable you to read out only the first Parameters Changed message Following isa programming example in BASIC for outputting an Execution Error OE Output either an Execution Error code number or message string from the Signal Generator address 19 and reset bit 2 of the Status Byte To output the message code number 10 OUTPUT 719 OE 20 ENTER 719 A To output the message string 10 OUTPUT 719 OE 20 ENTER 719 A Dummy read of the message code number 30 ENTER 719 A The above examples can also ve modifi
195. e and leave the rms detector enabled 2 Set the HP 8642 to the levels and frequencies in the following table and verify that the measuring receiver reading is less than the specified maximum HP 8642 FREQ 4 14 Performance Test 4 rev 08JUL88 Model 8642A B AM FM AND PM TESTS Specifications Performance Test 5 Performance Tests Electrical Characteristics Performance Limits Conditions AMPLITUDE MODULATION Depth Resolution Incidental PM Indicator Accuracy 0 to 99 9 0 1 0 20 radians peak 3 55 of reading 1 AM Level lt 10 1 kHz Rate 30 AM 8642A Bands 1 8 HET 8642B Bands 1 9 HET 8642A Band 9 8642B Band 10 1 kHz rate up to 90 AM 5 of setting 1 AM AM Distortion at 1 kHz rate 8642A Bands 1 8 Band 9 HET lt 1 lt 2 0 to 30 AM lt 2 lt 4 30 to 70 AM lt 4 lt 6 70 to 90 AM 8642B Bands 1 9 Band 10 HET lt 1 lt 2 0 to 30 AM lt 2 lt 4 30 to 70 AM lt 4 lt 6 70 to 90 AM FREQUENCY MODULATION 3 dB Bandwidth Internal 20 Hz to 100 kHz External ac 20 Hz to 200 kHz External dc dc to 200 kHz Maximum Peak Deviation The smaller of ac coupled 3 MHz or frog X 2160 band 10 and internal 1 5 MHz or frog x 1080 band 9 HET 750 kHz frog 540 band 8 375 kHz or frog x 270 band 7 187 kHz frnog X 135 band 6 93 8 kHz or fmoa X 67 5 band 5 1 46 9 kHz or fmoa X 33 75 band 4 23 4 kHz or finog X 16 88 band 3 11 7 kHz or fmoq X 8 44 band 2
196. e of the Auto Adjust Routines built into the HP 8642 The second field to the right of STAT is the date that the Cal Data was generated The date is shown in the form month date year MM DD YY The right most field is the five digit Cal ID Number which will conform to the last five digits of the serial number like designator for example 2412A 31458 that is on each module The following are some examples of the Stats Display on the HP 8642 09 STAT 9995 02 30 84 31458 A2 Cal Data Stats are Data generated using the built in A2 Auto Adjust Routine Febru ary 30 1984 and the A2 module Cal ID Number is 31458 02 STAT 0002 12 25 86 00903 A12 Cal Data Stats are Data generated at the factory on December 25 1986 and the A12 module Cal ID Number is 00903 04 STAT 0001 09 06 82 23010 A13 Cal Data Stats are Data generated at the factory on on September 6 1982 and the A13 module Cal ID Number is 23010 rev 13FEB90
197. e selected Either reduce M deviation or select an RF frequency that allows the deviation or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III PM LIMITS MAX FREQ E41 4041 The setting limits the maximum RF frequency value that can be selected Either reduce deviation or select an RF frequency that allows the deviation or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III FREQ LIMITS MAX PM E42 4042 The RF frequency setting limits the maximum value of deviation that can be selected Set the RF frequency to a value in a band that allows the desired value of deviation or select a deviation that is allowed ot the current RF frequency or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III FR SWP AUTO LIMITATION E45 4045 Stepped Frequency Sweep cannot sweep in the Auto sweep mode under the following conditions Setting start and stop end points if one end point is less than 4 130860 MHz with a second end point greater than 132 187500 MHz Setting a Stepped Frequency Sweep across 1057 500000 MHz in the 8642B If neither of these restrictions apply to the attempted setting refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III 3 187 Operation Model 8642A B Operating Messa
198. e the second time Refer to Queued Up Messages on page 3 180 for an explanation of the purpose of scrolling through the message list twice Also note that when this message is available the Knob might not operate in the normal way rev 20MAR85 3 193 Operation Model 8642A B Operating Messages cont d Information Messages Local These messages are automatically displayed when you execute a function HP IB Most of these messages can be output via HP IB using the Output Display capability after you execute a function 11 I2 159 and 160 cannot be read via HP IB To understand a way to read 141 through 149 and 151 through 159 refer to that message description on the following page Information messages message code is prefixed with I provide useful information about instrument settings or conditions INSTRUMENT PRESET J1 Instrument Preset is being executed Refer to Instrument Preset Partial Preset page 3 138 This message cannot be read via HP IB using Output Display because it automatically clears from the display after execution completes PARTIAL PRESET 12 Partial Preset is being executed Refer to Instrument Preset Partial Preset page 3 139 This message cannot be read via HP IB using Output Display because it automatically clears from the display after execution completes YYMMDD FIRMWARE CODE 13 This message is an example of the Signal Generator s display of the current firmware version which is accessed with
199. ecial Function 9 enables the Signal Generator to produce a 30 dB amplitude range with monotonic step to step amplitude increments The RF output can be turned off using two different methods One method turns off the output without adjusting the Signal Generators output attenuators The other method reduces the output below the lowest possible amplitude setting using the output attenuator and the automatic leveling control circuit Table 3 13 Output Amplitude Operating Characteristics Electrical Characteristics Performance Limits Conditions For the 8642A and 8642B RF Frequencies of 0 100000 to 264 375000 MHz except Heterodyne Band Resolution Absolute Level Accuracy Output Level Switching Time Output Impedance Flatness SWR Reverse Power Protection Third Order intermodulation 20 0 to 140 0 dBm 2 24V to 0 023 uV 4 49 EMF V to 0 046 EMF aV 127 0 to 33 0 dByuV 133 0 to 27 0 dB EMF uV 19 0 to 140 0 dBm 2 00V to 0 023 zV 4 01 EMF V to 0 046 EMF uV 4126 0 to 33 0 dB V 4132 0 to 27 0 dB EMF aV 418 0 to 140 0 dBm 1 78V to 0 023 4V 8 56 EMF V to 0 046 EMF uV 4125 0 to 33 0 dBuV 131 0 to 27 0 dB EMF 17 0 to 140 dBm 1 59V to 0 023 4V 3 19 EMF V to 0 046 EMF uV 124 0 to 33 0 130 0 to 27 0 dB EMF uV 16 0 to 140 0 dBm 1 41V to 0 023 pV 2 83 EMF V to 0 046 EMF uV 123 0 to 33 0 dBuV 4129 0 to 27 0 dB EMF 4V
200. econds 3 116 Mode 8642A B Operation Modulation FM cont d Related Operating Instructions Refer to Modulation Oscillator page 3 131 for more information on the internal modulation oscillator that is the common source for all internal modulation as well as for MOD OUTPUT connector Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed 3 117 Model 8642A B Description Operation MODULATION M The Signal Generator can phase modulate its RF output either with a variable internal modulation oscillator and or with an ac or dc coupled external source applied to the FM M INPUT Depending on the RF frequency selected the 8642A B has different limits on the possible deviation that can be selected See Figure 3 15 on page 3 120 The Signal Generator normally selects the divide bands to obtain its FM deviation However if the divide band s maximum internal FM deviation boundaries are crossed the Signal Generator can automatically switch to the heterodyne band which allows wider deviation at RF frequencies less than 132 187501 MHz Refer to RF Frequency page 3 39 for more information about these different bands Table 3 22 M Operating Characteristi
201. ed external source applied to the AM PULSE INPUT When amplitude settings exceed 14 0 dBm 1 12V 121 0 dBuV 2 25 EMF V and 127 0 dB uV the AM depth setting is limited Refer to Table 3 18 on page 3 102 Table 3 17 AM Operating Characteristics Electrical EA AM Depth 096 to 99 996 Output Amplitude lt 10 dBm 707 mV 1 41 EMF V 117 0 dB V 123 dB EMF aV Resolution 0 196 AM Indicator Accuracy 3 5 of setting 1 AM 8642A bands 1 8 HET 1 kHz rate up to 90 AM 8642B bands 1 9 HET 5 of setting 196 AM 8642A band 9 8642B band 10 AM Distortion at 1 kHz rate 8642A Bands 1 8 8642B Bands 1 9 196 096 to 3096 AM 296 30 to 7096 AM 496 70 to 9096 AM 8642A Band 9 HET 8642B Band 10 HET 296 096 to 3096 AM 496 30 to 70 AM 696 70 to 90 AM AM 3 dB Bandwidth dc to 100 kHz External dc bands 1 5 thru 10 Depth lt 90 20 Hz to 100 kHz External ac and internal bands 1 5 thru 10 dc to 20 kHz External dc bands 2 3 4 20 Hz to 20 kHz External ac and internal bands 2 3 4 Incidental M 0 2 radians peak 1 kHz rate and 30 AM lit is possible to set AM with an output amplitude above this limit However its modulation characteristics are not specified Specific band information is available in Table 3 11 3AM bandwidths up to 100 kHz can be obtained by selecting Special Function 8 Prefer Heterodyne Band Procedures Note Put the instrument in its initialize
202. ed to apply to an Output Parameters Changed OC message if you send OC instead of OE Sending either OE or OC alone program line 10 above will reset the appropriate status bit unless RQS is true in which case the Status Byte must be read again to clear the status bit Note that you should not execute an instrument function between setting up the instrument for data output and reading the data from the Signal Generator To illustrate this consideration refer to the OE example above If you were to insert a line 15 that set an instrument function such as AM the data received from the Signal Generator will be the display data not the Execution Error message code because AM would have superceded the OE data output preparation Hardware Errors Hardware Error messages are handled differently than Execution Error or Parameters Changed messages since more than one message can be present These messages are stored as a queued up list with a maximum number of 22 messages Read about queued up messages on page 3 180 To properly retrieve all the queued up messages follow the OH command with a software loop as shown in the sample program in Table 3 6 page 3 23 Operation x Model 8642A B Data Output cont d Gutput Active Function OA Output Active Function enables the Signal Generator to output the setting of a selected active function over HP IB The Signal Generator outputs a string that can be directly read
203. eep HP IB You can use the step keys HP IB UP DN to sweep in the manual sweep mode since Knob rotation is not possible via HP IB Single Sweep Selecting single sweep will start or restart a single weep Single sweep initiates one sweep only at the end of the sweep the output frequency remains at the final end point value SINGLE CSHIFT STOP AMPTD HP IB code FASG The SWPNG annunciator is displayed for the duration of the single sweep During Stepped Frequency Sweep you can the sweep and display the actual output frequency by selecting manual sweep When operating th instrument locally a single sweep can also be conveniently restarted by pressing the COFt ON key twice when in the single sweep mode Start frequency or stop frequency must te the active function in order to use the Off On function in this way 3 51 Operation Model 8642A B RF Frequency Sweep cont d TIME How to Set Sweep Time Sweep time setting limitations are different for Stepped Frequency Sweep and for Phase Continuous Frequency Sweep In all cases sweep time is set using the following procedure TIME SHET CSTART FREQ J and the value of the desired sweep time in s or ms MHZ V or KHZ MV respectively I Selecting TIME START FREQ alone displays the current sweep time setting If sweep time is not specified the Signal Generator uses the sweep time value last entered for either amplitude or frequency sweep
204. efore all internal modulation as well as MOD OUTPUT have the same modulation frequency 3 101 Operation Model 8642A B Modulation AM cont d HP IB Sequence Dependency AM settings are sometimes coupled with Attenuator Range Hold Special Function 9 or amplitude settings Therefore HP IB codes may need to be entered in a particular sequence when accessing combinations of these functions Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III Maximum Combinations of Amplitude and AM When amplitude settings exceed 14 0 dBm 1 12V 121 0 dBuV 2 25 V and 127 0 dB EMF uV the AM depth setting is limited to those settings listed below in Table 3 18 Table 3 18 Limitations on AM Settings with Amplitude 1 of 2 Maximum Amplitude AM Depth m m v ma mura 140 0 to 14 0 0 000023 to 1 12 33 0 to 121 0 0 000046 to 2 25 27 0 to 127 0 14 1 1 14 121 1 2 29 127 1 14 2 1 15 121 2 127 2 14 3 1 16 121 3 127 3 14 4 1 18 121 4 127 4 14 5 1 19 121 5 127 5 14 6 1 20 121 6 127 6 14 7 1 22 121 7 127 7 14 8 1 23 121 8 127 8 14 9 1 25 121 9 127 9 15 0 1 26 122 0 128 0 15 1 1 27 122 1 128 1 1 29 122 2 128 2 1 30 122 3 128 3 1 32 122 4 128 4 1 33 122 5 128 5 1 35 122 6 xz 128 6 1 37 122 7 128 7 1 38 122 8 128 8 1 40 122 9 128 9 1 41 123 0 129 0 1 43 123 1 129 1 1 45 123 2 129 2 1 46 123 3 129 3
205. elected 114 Negative Polarity This special function causes a positive voltage applied to the external INPUT to cause a phase lag and a negative voltage applied to cause a phase lead 115 Negative FM Polarity This special function causes a positive voltage applied to the external INPUT to cause a negative frequency shift and a negative voltage applied to cause a positive frequency shift 116 DC FM Correction Off This special function prevents the initial frequency correction that occurs when dc coupled FM is selected Normally when dc coupled FM is selected the FM phase lock loop is open causing an offset in the selected RF output frequency To correct this initial offset the dc coupled signal is momentarily switched off while an internal counter is used to determine the amount of RF frequency offset The frequency offset 1s then corrected and the dc coupled signal is switched back on DC FM Correction Disabling this correction causes a decrease in switching time by approximately 200 ms 117 DC FM Update Mode On With the FM loop unlocked RF output frequency changes with a change in applied dc signal and with the normal drift of an unlocked VCO that occurs over time and temperature In the DC FM Update Mode the Signal Generator measures and displays these RF frequency changes Refe to Modulation FM page 3 116 118 AC Coupled DC FM On When the Signal Generator is in the normal ac coupled FM mode the ext
206. ency NOTE External modulation frequency is not monitored by the Signal Generator The Signal Generator s modulation frequency display refers to the internal modulation oscillator only Depth CAM J and the desired modulation depth in per volt The modulation depth setting when using an external source sets the input sensitivity per volt not the actual depth A linear relationship exists between the AM depth setting and the external voltage applied for voltages less than or equal to approximately 1 2 Vpk 3 99 Operation Model 8642A B Modulation AM cont d HP IB Codes 3 100 NOTE With simultaneous internal and external modulation the external signals should not cause the AM depth to exceed 99 9 If this limit is exceeded the Signal Generator could go out of lock which causes queued up Hardware Error messages Also the external AM PULSE INPUT does not respond linearly to inputs greater than approximately 1 2 Vpk Example Amplitude modulate the RF output with an external 1 Vpk dc coupled source 80 AM depth at a rate determined by the external source s frequency AMXD AM 80 PC program codes Display w rara rama A r A A 7 ra ra 2 r i Ti UI d c v KI v v ie it c HAAPE HA lh FREQ LO AM EXT Dc AMPTD The RF output is being externally amplitude modulated with an external dc coupled source as indicated by the AM EXT and DC annunciators AM depth setting is 80 0X per volt Modulati
207. ency span Minimum sweep time in ms is equal to the max mum of 5 ms or Start Frequency in Hz Stop Frequency in Hz X Divide Number X 0 002 ms If the result is not an integer number of ms use the next highest integer number of ms For example if the result is 52 8 ms use 53 ms if the result is 52 0 ms use 52 ms Another example might be if the result is 3124 7 ms use 3 1 35 because only 3 digits can be entered for sweep time from the front panel if the result is 3120 ms use 3 12s 4 Calculate the maximum slowest sweep time setting for a desired non zero frequency span Maximum sweep time in s is equal to the minimum of 999s Or Start Frequency in Hz Stop Frequency in Hz X Divide Number X 5s 3 61 Operation Model 8642A B RF Frequency Sweep cont d 5 Calculate the automatically selected X axis steps for a desired sweep time setting Automatically selected number of X axis steps equals the minimum of 1023 Or Sweep Time in ms 1 ms Note The X Axis Output changes in steps while frequency changes in a phase continuous manner 6 Calculate the required sweep time to select a desired number of X axis steps The desired number of steps must be less than or equal to 1023 Sweep time in ms is equal to Desired Number of Steps X 1 ms Note The X Axis Output changes in steps while frequency changes in a phase continuous manner Example for Calculation 3 Phase Continuou
208. equency Refer to the discussion about FM Pre emphasis starting on page 3 113 under 6 FM Pre emphasis On Table 3 19 FM Operating Characteristics Electrical Characteristics Performance Limits Conditions FM Deviation Limitations See Figures 3 12 and 3 13 Indicator Accuracy 5 of setting 10 Hz Rates from 20 Hz to 100 kHz Resolution 0 7 of setting or 0 0004 of maximum deviation whichever is larger FM Distortion 4 For maximum dc coupled deviation Rates from 20 Hz to 100 kHz 2 For e maximum dc coupled deviation 0 496 For 1s maximum dc coupled deviation FM 3 dB Bandwidth dc to 200 kHz External dc source 20 Hz to 200 kHz External ac source 20 Hz to 100 kHz Internal source 0 4 Hz to 200 kHz with Special Function 5 rev 07JUNE85 3 105 Operation Model 8642A B Modulation FM cont d 2160Yx 1080Y 540Y MAXIMUM FM 270Y DEVIATION Hz INT Hz per volt EXT 135Y 67 5Y YeModulation Frequency 33 75Y B 4375Y RF FREQUENCY MHz Actual band boundaries are listed in Table 3 11 8542B ONLY Figure 3 12 FM Deviation Limitations for each RF Frequency Band Modulation Frequencies 1389 Hz Internal external ac coupled or the internal and the external ac coupled FM source summed together Note The Y in each of the Y axis values represents the desired modulation frequency value in Hz Multiply the numeric value in the Y axis times the desired modulation frequency value to determ
209. erating Messages discussed in this instruction are grouped into six categories Parameters Changed messages page 3 182 Execution Error messages page 3 184 Hardware Error messages page 3 193 Information messages page 3 194 Prompt messages 3 196 and Out Of Lock messages 3 197 Messages are displayed in a format that shows the wording of the message followed by an alphanumeric code Alphanumeric codes combine a letter and a number for example C31 The message listing lists the messages as they are displayed with the alphanumeric code to the right of the message wording not to be confused with the message code number in the right margin of the listing The messages are listed in alphanumeric order Refer to either the 8642A B On Site Manual or the 8642A B Service Manual for information regarding Service and Calibration Messages that are not mentioned in this Operating Manual When Using the Instrument Locally You will usually be able to view each message whenever the Signal Generator is ready to give you information That is you don t need to do anything to the instrument to see a message However when you execute some instrument functions a message is queued up and be displayed using the CMSSG_ key these messages are noted in the listing The MSSG annunciator in the right portion of the display notifies you that a message is queued up To read queued up messages just select the MSSG J key repeatedly When you rea
210. erify that the power readings on the measuring receiver are within the specified limits rev 08JUL88 Performance Test 1 4 5 Performance Tests 4 6 HP 8642 AMPTD dBm 1 On the HP 8902A Measuring Receiver press CALIBRATE before continuing test 8642 FREQ MHz G GO G Ww QO O Measuring Receiver Frequency e U G WWW WwW Oo Q Qo Measuring Receiver Mode RF POWER RF POWER RF POWER TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF RF POWER RF POWER RF POWER TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF 79 43E 03 7 762E 03 2 510E 03 0 794E 06 79 43E 06 7 943E 06 794 3E 09 79 43E 09 7 943E 09 794 3E 12 79 43E 12 7 943E 12 794 3E 15 79 43E 15 7 943E 15 794 3E 18 158 5E 18 79 43E 03 7 762E 03 2 510E 03 794 3E 06 79 43E 06 7 943E 06 794 3E 09 79 43E 09 7 943E 09 794 3E 12 79 43E 12 7 943E 12 794 3E 15 79 43E 15 7 943E 15 794 3E 18 158 5E 18 Model 8642A B 125 9E 03 12 30E 03 3 981E 03 1 259E 03 125 9E 06 12 59E 06 1 259E 06 125 9E 09 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 125 9E 15 12 59E 15 1 259E 15 251 2E 18 125 9E 03 12 30E 03 3 981E 03 1 259E 03
211. ernal signal is applied to the FM loop through circuitry that uses a phase lock loop to ensure the accuracy of the output signal In dc coupled FM DC FM the phase lock loop is unlocked and the external signal is applied directly to th unlocked VCO With Special Function 118 selected the input signal is ac coupled to the unlocked FM VCO blocking any applied dc component Typical low frequency corner frequency is 1 Hz Using DC FM avoids the phase shifts associated with ac coupled FM circuitry and allows maximum stereo separation An external dc coupled FM source must be in use with Special Function 118 to get these benefits 119 Disable Settling This special function allows the Signal Generator s microprocessor to respond to new commands without waiting for the internal circuitry to settle improving response time by up to 40 ms When using this special function it s possible te select a function before the previous function has finished settling Also Special Function 119 disables out of lc gt e ssages 3 173 Operation Model 8642A B Special Functions cont d DETAILED DESCRIPTIONS OF ALL SPECIAL FUNCTIONS cont d 121 Sweep Up and Down On Sweep Up and Down is a type of sweep that causes the Signal Generator to sweep from the start end point to the stop end point and then from the stop end point to the start end point in the same amount of time during auto or single sweep modes See Figure 3 7 Sweep Waveforms in RF Frequency Sweep
212. es Input Syntax 4 DATA INPUT Data can be input to the Signal Generator using either front panel keystrokes or via HP TB To address the Signal Generator via HP IB the input data information usually contains the universal unlisten command the Signal Generator s listen address the controller s talk address and a string of HP IB program codes The following Table 3 2 shows some possible Signal Generator settings and corresponding HP BASIC commands Table 3 2 Data Input Example Input Data HP BASIC Set frequency to 123 4 MHz OUTPUT 719 FR 123 4 MZ Set amplitude to 10 dBm OUTPUT 719 AP 10 DM Set amplitude increment to 10 dB OUTPUT 719 APIS 10 DB APDN APDN decrement amplitude 20 dB Examples assume Signal Generator s address 19 Refer to your controller manual for command syntax and the controller s address The Signal Generators functions can be accessed with specific program codes These program codes are summarized in HP IB Codes Summary in Table 3 8 Signal Generator Function to HP IB Code page 3 32 and Table 3 9 Signal Generator HP IB Code to Function page 3 33 In addition most HP IB codes are printed on the instrument s front panel in light gray print near the code s associated key Input data information consists of one or more bytes sent over the bus eight data lines when the bus attention control line ATN is false and when the Signal Generator is remote and addressed to liste
213. esult be non integer but actual frequency points truncated to 1 Hz the total number of points is equal to the total number of steps 1 The sweep step size is the maximum of 1 H or Start Frequency in Hz Stop Frequency in Hz 1023 or Start Frequency in Hz Stop Frequency in Hz Sweep Time in ms Min Dwell Time in ms INTEGER OF 3 Calculate a sweep time that could be selected for a desired number of steps 3a First you must ensure that the desired number of steps is between the maximum and minimum number of steps possible The maximum number of frequency steps is equal to the minimum of 1023 Or Start Frequency in Hz Stop Frequency in Hz 1 Hz The minimum number of frequency steps equals the minimum of INTEGER OF Min Dwell Time in ms J Or Start Frequency in Hz Stop Frequency in Hz 1 Hz 3b If the desired number of steps is equal to the maximum use a sweep time setting in ms equal to or greater than the result of the following equation Number of Steps 1 x Min Dwell Time in ms 3 54 Model 8642A B Operation RF Frequency Sweep cont d If the desired number of steps is less than the maximum calculated in 3a use a sweep time setting in ms greater than or equal to the result of the above calculation but less than the result of the following calculation Number of Steps 2 x Min Dwell Time in
214. f the stop amplitude 3 During auto or single sweep you can stop the sweep and display the actual output amplitude by selecting manual sweep MANUAL SHFT STOP FREQ Selecting either CAMPTD CAM PULSE CSHET CSTART FREQ STOP FREQ or RE OFF ON will also turn off the sweep but may cause a Parameter Changed message These mesages are discussed in Operating Messages page 3 182 AUTO MANUAL SINGLE How to Select a Sweep Mode Sweep modes available are auto manual and single CSTART AMPTD or STOP AMPTD must first be selected before one of the amplitude sweep modes can be selected Model 8642A B Operation Amplitude Sweep cont d Auto Sweep Auto sweep continually repeats the sweep sequence from start amplitude to stop amplitude AUTO START AMPTD HP IB code AASA The SWPNG annunciator is continuously displayed The auto sweep can be stopped to display the actual output amplitude by selecting manual sweep Manual Sweep Selecting manual sweep does not start a sweep but enables the Knob or the Step keys to control an amplitude sweep MANUAL CSHIET CSTOP FREQ J HP IB code AASM Turn the Knob or select the Step keys to sweep between end points The actual output amplitude as well as the SWPNG annunciator are displayed during the amplitude sweep HP IB You can use the step keys HP IB UP DN to sweep in the manual sweep mode since Knob rotation is not possib
215. for example Special Function 9 Select Special Function 100 Special Function Codes Less Than 200 Off to turn off Special Functions 4 through 9 111 through 9 121 through 123 134 and 135 e Select INSTR PRESET HP IB IP o PARTIAL SHEET INSTR PRESET HP IB PP How to Display the Special Functions Currently On SPCL CSHIFT When SPCL is selected the codes of the currently selected special functions will be displayed in numeric order As each special faction is selected it is placed in numeric order in that list HP IB Use Output Display to read these special functions Refer to the discussion about outputting display information which begins on page 3 21 in the HP IB portion of this Section RF Frequency can be varied by 0 1 Hz using Special Functions 240 and 241 The status of these is read using the MSSG key Refer to page 3 195 Information Messages 149 through 141 and 151 through 159 HP IB Codes The HP IB code for special function is SP When selecting a special function via HP IB use the number of the special function preceded by SP for example SP4 or SP204 Exactly one or three digits must always be used to select special functions Leading zeroes must be suppressed for special functions even though they are required for some other functions such as SV RC and SS SPCL HELP HELP OFF Related Operating Instructions Refer to Operating Messages page 3 177 if the in
216. for the HP 8642A B Signal Generator Order the Rack Slide Kit for instrument cabinet frames assembled with metric hardware as HP part number 08642 80059 Order the Rack Slide Kit for instrument cabinet frames assembled with English hardware as HP part number 08642 80058 Note that if metric hardware is used the rear panel of the instrument mentions that fact rev 30SEP88 1 5 General Information Model 8642A B 1 11 HOW TO USE THE RECOMMENDED TEST EQUIPMENT TABLE Table 1 3 lists the test equipment required for testing adjusting and servicing the Signal Generator The critical specification column describes the essential requirements for each piece of test equipment Other equipment can be substituted if it meets or exceeds these critical specifications Alternate models are suggested in Table 1 4 Some reasons for recommending an alternate model might be its HP IB compatibility or its ability to replace two or more single models 1 12 INSTRUMENTS COVERED BY THIS MANUAL 1 6 Serial Numbers Attached to the instrument is a serial number plate The serial number is in the form 0000A00000 The first four digits and the letter are the serial prefix The last five digits form the suffix that is unique to each instrument The contents of this manual apply directly to instruments having the same serial prefix es as those listed at the beginning of Volume 1 Manual Updates An instrument manufactured after the printing of this manual ma
217. for the MOD OUTPUT connector Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed Model 8642A B Operation MODULATION OSCILLATOR Description The Signal Generator s internal modulation oscillator is the modulation source for internal AM FM M and pulse modulation The modulation oscillator signal is also the source for the MOD OUTPUT connector when the modulation output level is set Internal modulation such as AM FM and pulse modulation is described in those specific operating instructions However the modulation frequency and the modulation output level are discussed here Table 3 24 Modulation Oscillator Operating Characteristics Electrical Performance GE Characteristics Limits onditions Frequency Range 20 Hz to 100 kHz Frequency Resolution 196 of setting Frequency Accuracy 296 of setting Output Distortion 20 5 Vpk 0 0296 0 02 to 15 8 kHz 0 1596 215 8 kHz Output Level Range 0 to 3 3 Vpk into 600 ohms Output Level Resolution 4 mV Output Level Accuracy 4 15 mV Within 1s Output Impedance 600 ohms 10 Procedures Note Put the instrument in its initialized state by selecting INSTR PRESET J MOD FREQ How to Set Modulation Frequency and the value of the desired output frequency in kHz or Hz The modulation frequency cannot be turned off with the COEF ON
218. ful in instru ment applications INTERNAL REFERENCE OSCILLATOR EXTERNAL REFERENCE isti High Stabili input rear panel Characteristic Standard ont ont lucos UE usus Level lt 6 Vp p Aging rate 2 ppm year See Tabie 1 1 impedance 50 ohms Temperature 4 ppm 0 to 55 C 7 10 9 0 to 55 Line voltage 0 1 ppm 3 x 1079 5 10 5 10 Output rear panel Frequency 10 MHz Level gt 1 4 Vp p into 50 ohms Impedance 75 ohms rev 18MAY89 Model 8642A B General Information Table 1 3 Recommended Test Equipment 1 of 2 Frequency Range 100 kHz 2115 MHz Accuracy 0 1 dB HP 3456A A T Sensitivity 10 uV Frequency Standard Frequency 10 MHz HP 5065A Long Term Stability 1 10 10 24 hours SWR lt 1 3 Low Noise Amplifier Input Output Impedance 50 ohms HP 08640 60506 instrument Critical Specification Recommended Model Use Digital Voltmeter DVM Accuracy 472 digit 0 05 reading 1 digit Frequency Bandwidth 1 kHz to 1 MHz Requires 19 25 Vdc Attenuator Fixed Attenuation As required by performance test HP 8491A M Range 10 mV to 600V Noise Figure 3 dB Power Supply Gain 40 1 dB Low Pass Filter Bandwidth 1 MHz See Figure 1 1 Impedance 50 ohms Measuring Receiver Modulation HP 8902A Accuracy 2 of reading AM Rejection 30 Hz at 5096 AM 8 kHz BW FM Rejection 0 296 AM 50 kHz FM
219. function code for example when using UP or DN with SV RC HP or SM Operation Model 8642A B x HP IB RELATED FRONT PANEL KEYS 8642B SIGNAL GENERAN 0 1 2100 MHz ENT ADRS This function enables you to view or set the HP IB address from the front panel This key enables you to return to local from remote MODULATION SOURCE py You can view or set the RQS mask from the front panel by selecting the keys I Figure 3 5 HP IB Related Front Panel Keys 3 34 Model 8642A B Operation HP iB RELATED TERMS active function prefix Many HP IB codes shouid not be entered without being prefixed by an active function code For a list of the active function codes and the codes that should be prefixed with an zctive function code refer to Table 3 8 Signal Generator Function to HP IB Code page 3 32 or Table 3 9 Signal Generator HP IB Code to Function page 3 33 alphanumeric The 8642A B has an alphanumeric display that is the display can show both alphabetic and numeric characters ASCII ASCII is an abreviation for American Standard Code for Information Interchange pronounced ask ee RQS RQS request service is from the Signal Generator s point of view The request service RQS bit is in the 8642A B Status Byte This bit affects when the service request SRQ line is pulled on the HP IB interface Refer to page 3 27 SRQ SRQ is from the HP IB con
220. g the Shift key twice can be used to clear the special function description from the display and return the display to showing normal instrument settings Figure 3 18 Special Function Related Keys Model 8642A B Description Procedures HELP Operation SPECIAL FUNCTIONS Special functions enable the Signal Generators uses to be extended beyond the functions normally available from dedicated front panel keys Some of the more frequently used special functions have an abbreviation printed on the front panel in light gray print above the appropriate Data keys not to be confused with the HP IB codes also in light gray print next to most keys In this instruction the special functions are listed in both functional order page 3 170 and in numeric order page 3 171 The listing in numeric order provides a brief explanation of each special function Also if appropriate we refer you to a Detailed Operating Instruction which discusses that special function in more detail The Help function enables you to view on the front panel the code and description of each special function Note Put the instrument in its initialized state by selecting INSTR PRESET To turn on any of the special functions use SPCL SHET J followed by the code number of the special function To list any currently activated special functions select SPCL Cz alone To display the number and description of any special function u
221. ge The display could resemble a Knob Hold condition when the frequency relative display is less than or equal to 2000 MHz Refer to Range of Relative RF Frequency Settings on page 3 47 One cursor above the second letter of the units specifier v lA TA TA MI gt AA FA TAA GSOSBRABBOMN2Z 5 Ld uv L Indicates that the function is the active function and Knob Increment is selected when you turn the Knob this function s value will change by the increment set value Two cursors in the display l A cursor above a digit and a cursor above the first letter of the units specifier FATA AMPTD G 4 0 HA d L FREQ AM Indicates that Knob Hold is activated over that function turning the Knob will change the digit under the cursor When you press the Step keys or any Data keys or the Off On key if applicable either the displayed function s value will change if it is also the active function or the active function will appear in the display and its value will change cursor above each letter of the units specifier t FA rA ITI 7 mz BPE Indicates that both Knob Hold and Knob Increment are activated over that function When you turn the Knob that function s value will change by the Increment Set value When you press the Step keys or any Data keys or the Off On key if applicable either the displayed function s value will ch
222. ge reduction make sure the common terminal is connected to the earth terminal of the power source Servicing instructions are for use by service trained personnel only To avoid dangerous electric shock do not perform any servicing unless qualified to do so Adjustments described in the manual are per formed with power supplied to the instrument while protective covers are removed Energy available at many points may if contacted re sult in personal injury Capacitors inside the instrument may still be charged even if the instrument has been dis connected from its source of supply For continued protection against fire hazard replace the line fuse s only with 250V fuse s of the same current rating and type for exam ple normal blow time delay etc Do not use repaired fuses or short circuited fuseholders 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 shipment During the warranty period Hewle
223. ges cont d TURN OFF SWEEP FIRST E46 4046 Turn off frequency sweep first To access Special Function 123 Phase Continuous Frequency Sweep turn off the start and the stop frequency that was set for the Stepped Frequency Sweep If this solution does not apply to your attempted setting refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section HP IB Send FAOF FBOF before SP1 23 FREQ SWP SP8 LIMIT E47 4047 Stepped Frequency Sweep cannot sweep in the auto sweep mode across 132 187500 MHz with Special Function 8 Prefer Heterodyne Band selected Either select Special Function 208 Prefer Divide Bands or select manual or single sweep or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III FR SWP SP223 LIMIT TIME E48 4048 Special Function 223 Stepped Frequency Sweep limits the minimum sweep time that can be selected Either turn off frequency sweep HP IB FAOF FBOF before setting the sweep time or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III FREQ SWP SWP TIME LIMIT E49 4049 The start or stop frequency setting is limited by the currently selected combination of Phase Continuous Frequency Sweep Special Function 123 and the current sweep time setting and possibly the current start and stop frequency settings and possibly Special Function 8 Prefer Heterodyne Ba
224. hat will provide related information about the topic or topics you are reading about Model 8642 3 Operation OC EXE JG teat Ea ENTRY E Se mec These keys make the main functions of the Signal Generator active functions so they can be set using FREQ one either Data keys the Knob Step keys or the Off On key The cursor designates which function is active The blue Shift key enables you to access the functions labeled in blue DATA TTT 5 E These keys are used to set the values of the Signal LIRE x Generator functions OMOMG The Knob usually modifies a specific digit in the display The keys select which digit will be modified The keys can also select Knob Hold or Knob Increment The Step keys enable you to step a function by the value that was set using the key The Off On key toggles an active function off or on with a single keystroke Figure 3 1 An Overview of the Basic Functions of the 8642A B 3 3 Operation Mode 8642A B 10 MHz OVEN OUT is the Option 001 high Stability time base output This output is connected to the external reference input to obtain improved stability HP IB connector is used to connect the Signal Generator to an external controller for remote Operation EXT REF INPUT locks to 1 2 5 or 10 MHz Z AXIS output provides a blanking
225. have been cleared with Special Function 251 Clear Recall Registers or because of a hardware error This error E93 occurs simultaneously with hardware error H10 Refer to Recalling an Undefined Register on page 3 162 for more information SEQ NOT SET 4 DIGITS E94 4094 Sequence was not set 4 digits are required Try the sequence setting again using two digits for both the start and stop sequence register numbers ADRS VALID 0 30 ONLY E95 4095 HP IB addresses are valid only between 0 and 30 Select an HP IB address between 00 and 30 or select 31 for Listen Only capability MASK VALID ONLY 0 255 E96 4096 The RQS mask is valid only between decimal 0 and 255 Set the RQS mask between those values 3 192 rev 20MAR85 Model 8642A B Operation Operating Messages cont d Hardwate Error Messages Local These messages are all queued up and be displayed using the MSSG key HP IB All of these messages are output via HP IB using OH Some out of lock messages are also output using refer to page 3 197 Hardware Error messages message number is prefixed with H signal the presence of either an internal circuit hardware problem or a firmware problem that you might be able to resolve Hardware Error messages may occur independently of function execution A maximum of 20 Hardware Error messages can be queued up to be accessed either by the CMSSG J key on the front panel or via HP IB using OH If you are unable to repair
226. he carrier and the modulation oscillator output MOD OUT is off Modulation Switching Time The time required to turn on the internal modulation oscillator or to switch between modulation frequencies can be reduced by approximately 200 ms depending on modulation frequency with a loss in modulation frequency accuracy by selecting Modulation Frequency Correction Off Special Function 113 For more information refer to Speeding Up Modulation Switching Time on page 3 132 The time required to turn on the internal modulation oscillator is increased by approximately 200 ms if DC FM Update Mode Special Function 117 is active For more information refer to 117 DC FM Update Mode On page 3 116 When switching from a dc coupled FM source for example EXT DC or INT EXT DC toa non dc coupled FM source RF frequency can take up to 2 seconds to settle to within 100 Hz of the selected frequency Selecting Heterodyne Band Operation Special Function 8 Prefer Het Band can be used to cause the Signal Generator to operate in the heterodyne band regardless of FM deviation whenever RF frequency is less than 132 187501 MHz This function prevents the Signal Generator from switching from the heterodyne band when it would be possible to use the divide bands Refer to How to Select the Het Band on page 3 41 Mixed Modulation The Signal Generator can simultaneously modulate the RF signal with more than one modulation type The Signal Generator doe
227. he time T1 in seconds 5 Wait for a period of time from 3 to 24 hours and re measure the phase change time T2 Record the period of time between measurements in hours 2 s Ta3 _ h 6 Calculate the aging rate from the following equation _ 1 cycle 1 1 T Aging Rate f Wa 73 where 1 cycle the phase change reference for the time measurement in this case 360 degrees f 8642 s reference output frequency 10 MHz T specified time for aging rate 24h T1 initial time measurement s for a 360 degree 1 cycle change T2 final time measurement s for a 360 degree 1 cycle change T3 time between measurement s h for example if T1 351s T2 349s 3h then _ 1 cycle 1 1 24h i i 5 wa ssi 5 3h 1 306 x 107 7 Record the aging rate Aging Rate 5 x 1071 day 4 46 Performance Test 15 rev 08JUL88 Model 8642A B Performance Tests NOTE If the absolute frequencies of the frequency standard and the HP 8642 s reference oscillator are extremely close the measurement time in steps 4 and 5 T1 and T2 can be reduced by measuring the time required for a phase change of something less than 360 degrees Change 1 cycle in the formula for example 180 degrees 1 2 cycle 90 degrees 1 4 cycle 8 If the aging rate is not within the required tolerance check the power supplies before replacing Be sure sufficient warm up time has been allo
228. hen connected to an appropriate poser receptacle this cable grounds the instrument cabinet The type of power cable plug shipped with each instrument depends on the country of destination Refer to Table 2 1 on page 2 4 for the part numbers of the power cables and Mains plugs a1lable Installation Model 8642A B Table 2 1 AC Power Cables Availiable P O ERRATA Cable Plug Cable For Use HP Part Description Length In Country Number inches 8120 1351 90 STR BS1363A Mint Gray United Kingdom 8120 1703 90 90 Mint Gray Cyprus Nigeria Rhodesia Singapore 8120 1369 STR STR Austrailia 8120 0696 NZSS198 ASC112 New Zealand STR 90 8120 1689 STR STR Mint Gray East and West 8120 1692 STR 90 Mint Gray Europe Saudi Arabia Egypt unpolarized in many nations 8120 1378 STR STR NEMA5 15P Jade Gray United States 8120 1521 STR 90 Jade Gray Canada Mexico Phillipines Taiwan 8120 1751 STR STR 90 Jade Gray U S Canada 1 100V 8120 4753 STR STR 90 Dark Gray Japan only Same plug as above 8120 4754 STR 90 90 Dark Gray Japan only 8120 2104 3 STR STR SEV1011 79 Gray Switzerland 1959 24507 Type 12 8120 2296 STR 90 Gray 8120 3997 STR 90 Gray 8120 0698 STR STR NEMA6 15P United States Canada 8120 2956 90 STR Denmark 8120 2957 90 90 8120 3997 STR STR 8120 4211 STR STR IEC83 B1 South Africa India 8120 4600 STR 90 8120 1860 STR STR CEE22 V1 Jade Gray Systems Cabinet Use 8120 1575 STR
229. ial order in a block of unused registers Recalling an Undefined Register Recalling a register that is not defined causes messages E93 RECALL NOT DEFINED E93 and H10 RECALL ERROR FOUND H10 These messages could be caused because of a previous execution of Special Function 251 Clear Recall Registers RAM being lost for example if the battery lost its charge or recalling a register before anything is saved in that register HP IB Execution Error message E93 occurs immediately after recalling an empty register So by noting the occurrence of E93 by enabling execution errors to pull SRQ refer to Service Request on page 3 27 in the HP IB portion of this Section III you could find out which register you recalled was not defined Model 8642A B Operation Sequence cont d How to Conveniently Modify Recall Registers in the Sequence SEQ used in conjunction with SAVE can be used to conveniently modify recall registers in the sequence Just select SEQ J until the desired register is recalled then modify the instrument state and re save it by selecting SAVE J J How to Skip Directly to a Specific Recall Register in the Sequence You can conveniently skip directly to any recall register in the sequence by just recalling that register directly by register number then continuing on in the sequence from that register by just selecting SEQ Related Operating Instructions Refer to Save Recall page 3 157 for information o
230. ible deviation is 1 500 MHz not 1 501 MHz How to Put the Increment Set Value on the Knob Select KNOB INCR SHET gt to use the Knob to change function values by the increment set values With Knob Increment the function s value will change approximately 15 increments per revolution when the Knob is turned Refer to Knob page 3 142 for more information about putting the increment set value on the Knob using the Knob Increment functions Negative Values Are Not Possible with Increment Set The Signal Generator only accepts positive increment set values Specifying a negative increment value selects the absolute value of that number Refer to Instrument Preset Partial Preset page 3 139 for information about setting the instrument to an initialized state that maintains increment set values Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified 3 151 Model 8642A B Description Procedure Example HP IB Codes Operation ENTRY OFF Entry Off when selected can guard against someone accidentally changing the output signal by inadvertantly bumping the Knob or pressing a key for example while connecting output cables Entry Off disables the active function as well as the following Signal Generator functions STEP and hc KNOB KNOB HOLD KNOB INCR DATA selection and Cursor positioning C and Note Put the instrument in its initialized state by selectng I
231. ilable With the Instrument 0 0 0 00 000 eee lee 1 4 Electrical Options 5 66 ed bus aha ae ASA S TRIGO s Bev ELE PANE RUN Me TS 1 4 Mechanical Options eee a l s v ucu s S pun k uq e es 1 4 Documentation Options 2 2222 esas 1 5 Equipment That Can Be Ordered For the 1 5 Generator Z 5s we eS us RR S Bes dey eo NR UR ER eire sedet DU Roe un hon Bs 1 5 On Site Service Kits a suu cuero Rug Y eR posce a ik odo Te 1 5 Bench Service Kits 52 uus recs c re a eT Se Pac abi Reg 1 5 Signal Generator Test System 8902 5 1 5 500 to 750 Adapter ataia soe bce ar dy ate ne avg eee Bear Gib aie asda te Guus amp Bean fans 1 5 Fiberglass Transit Case ee es 1 5 Rack Slide Kit ouai Li dv Veo obe EU que ee ed AES E ACES 1 5 How to Use the Recommended Test 1 6 Instruments Covered By This 1 1 6 Table 1 1 Specifications 5 oue o uk or rem A E RW RSS ER LEE 1 7 Table 1 2 Supplemental Characteristics aaa e 1 13 Table 1 3 Recommended Test Equipment 1 15 Figure 1 1 1 MHz Low Pass Filter ee 1 16 Table 1 4 Alternative Test Equipment 1 16 Table 1 5 HP 11801C On Site Service Ki
232. ine the deviation limits For example to determine the maximum possible value of FM deviation for an RF frequency of 500 MHz the X axis value and a desired modulation frequency of 1000 Hz multiply 540 times 1000 This calculation results in 540 kHz which is the maximum possible FM deviation for these settings MAXIMUM DEVIATION 187 5 kHz INT kHz per 93 75 volt EXT 46 875 23 4375 11 71875 66 132 264 528 1057 2115 RF FREQUENCY MHz Actual band boundaries are listed in Table 3 11 w8642B8 ONLY Figure 3 13 FM Deviation Limitations for each RF Frequency Band Modulation Frequencies 1389 Hz Internal external dc coupled or the internal and an external dc coupled FM source summed together You can determine whether the Signal Generator will select a divide band or the heterodyne band Assume an RF frequency of 100 MHz If you select a deviation of 90 kHz the Signal Generator will use divide band 6 since the maximum possible deviation for band 6 is 187 5 kHz unless Special Function 8 Prefer Heterodyne Band is selected If you select 700 kHz deviation the Signal Generator will automatically select the heterodyne band Note that maximum possible deviation for the heterodyne band is 1500 kHz 4 106 rev 070CT87 Model 8642A B Operation Modulation FM cont d Procedures Note Put the instrument in its initialized state by selecting INSTR PRESET FM can be configured to use either the Signal Generator s internal
233. ing from relative units to absolute units before outputting the active function Refer to page 3 205 for amplitude units conversion information OA can be sent without a function prefix The first two characters in the output string will designate the active function If the Signal Generator does not have an active function when it receives OA without a function prefix it will output the display string which is the default HP IB output Model 8642A B Operation lt gt Table 3 4 Output Active Function String Formats Frequency Value could be negative if Frequency is relative Amplitude in dBm in dB relative dB EMF relative dBuV dB EMF uV in volts or EMF volts AM FM M Modulation Frequency Modulation Output Level Start Frequency Stop Frequency Start Amplitude in dBm in volts or EMF volts Stop Amplitude in dBm in volts or EMF volts Sweep Time Leading zero digits greater than the one s digit are suppressed FR sdddddddddd 0 HZ AP sddd d DM AP sddd d DB AP d ddddddddd VL AM dd d PC FM ddddddd 0 HZ PM ddd dddddd RD MF dddddd d HZ ML d dddd VL FA dddddddddd 0 HZ FB dddddddddd 0 HZ AA sddd d DM AA d ddddddddd VL AB sddd d DM AB d ddddddddd VL ST ddd ddd SC 3 19 Operation Model 8642A B ux Data Output cont d Output HI LO Status OL Output HI LO status enables an HP IB Controller to monitor the level of the external
234. ing the tion BNC Signal Generator Model 8642A B General Information Table 1 5 HP 11801C On Site Service Kit 1 of 2 HP Part Reference DEM eem se 08642 60889 08642 69889 08642 60890 08642 69890 08642 60891 08642 69891 08642 60892 08642 69892 08642 60893 08642 69893 08642 60894 08642 69894 08642 60895 08642 69895 08642 60896 08642 69896 08642 60897 08642 69897 08642 60898 08642 69898 08642 60899 08642 69899 08642 60842 08642 69842 08642 60843 08642 69843 08642 60844 08642 69844 2110 0010 2110 0002 2110 0036 2110 0004 08642 60845 08642 69845 08642 60133 08642 69133 08642 80019 2110 0003 5021 0844 1250 0832 1250 1697 1250 0827 8710 0033 9222 0779 9222 0698 8710 1465 8710 1493 8710 1541 08662 60080 08662 60075 1400 0249 ON NO OO ON RO WO NA ON OH oo o NN N i ON NA Wo NA b b A d A AAG Keyboard LCD Display Module Keyboard LCD Display Module Restored Modulation Module Modulation Module Restored Processor Memory Module Processor Memory Module Restored Latch Module Latch Module Restored FM Loop Counter Timebase Module FM Loop Counter Timebase Module Restored SAWR Loop Module SAWR Loop Module Restored IF Loop Module IF Loop Module Restored
235. into a numeric variable or into a string variable which includes the HP IB codes for both the function and its units specifier maximum of 19 characters Following is a programming example in BASIC for outputting the active function OA Output the RF frequency setting as either a numeric value or a string from the Signal Generator address 19 OA should be preceded by the function s HP IB code To output the numeric value 10 OUTPUT 719 FROA 20 ENTER 719 V Value is output in Hz To output the alphanumeric character string 10 CUTPUT 719 FROA 20 ENTER 719 AS The functions and values that can be output over HP IB using OA are listed below along with some format parameters Meanings of Values That Could Be Output 200 indicates the function is off 201 indicates RF OFF for amplitude only 202 indicates reverse power is tripped for amplitude only A space character is placed before and after the numeric portion of the string Output String Formats Table 3 4 Output Active Function String Formats on the following page lists the output format for each active function string The meanings of symbols in Table 3 4 are as follows 5 sign character either or d digit Leading zero digits greater that the one s digit are suppressed Comments If a function s value is in relative units the displayed relative setting not the absolute setting will be output You can output absolute units by convert
236. invalid special function number was selected Select a special function number that exists Refer to Special Functions page 3 171 SOME SPCLS STAYED ON E87 4087 Some special functions remained selected after you selected Special Function O or 100 because certain special functions were coupled to other instrument settings This message will only occur if more than one special function remains on Special Function 0 or 100 not turning off just one special function will display a message describing the reeson that one special function was not turned off View the special functions to see which are still on by selecting SPCL J J HP IB Use SP and read the display refer to the Output Display information discussion that begins on page 3 21 The special functions might remain selected because of a sequence dependency problem Possibly refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III 0 9 HZ LIMIT REACHED E88 4088 A maximum RF frequency change of 0 9 Hz can be accumulated using Special Function 240 Decrement Frequency 0 1 Hz or Special Function 241 Increment Frequency 0 1 Hz To get another 0 1 Hz step directly set the RF frequency to 1 Hz resolution SAVE RECALL MAX 50 E92 4092 The maximum recall register number is 50 Select register numbers only between 00 and 50 RECALL NOT DEFINED E93 4093 No instrument settings are saved in this register The register could
237. ion and prevent movement in the container Protect the front panel with cardboard 4 Sealthe shipping container securely 5 Mark the shipping container FRAGILE to ensure care ul handling 2 6 rev 20M AR85 Model 8642A B Installation SIGNAL GROUND SHIELD CONNECT TO P O TWISTED PAIR WITH 11 ATN EARTH P O TWISTED PAIR WITH 10 SRQ GROUND SHOULD BE GROUNDED J P O TWISTED PAIR WITH 9 IFC NEAR TERMINATION P 0 TWISTED PAIR WITH 8 NDAC OF OTHER WIRE OF P O TWISTED PAIR WITH 7 NRFD TWISTED PAIR P O TWISTED PAIR WITH 6 DAV REN EOI DIO 8 DIO 4 DIO 7 DIO 3 DIO 6 DIO 2 DIO 5 DIO 1 ISOMETRIC THREAD M3 5 x 0 6 24 PIN MICRO RIBBON SERIES 57 CONNECTOR Logic Levels The Hewlett Packard Interface Bus logic levels TTL compatible i e the true 1 state is 0 0 to 0 4 Vde and the false 0 state is 2 5 Vdc to 5 Vdc Programming and Output Data Format Refer to Section IIl Operation Mating Connector HP 1251 0293 Amphenol 57 30240 Mating Cables Available HP 10631A 1 metre 3 3 ft HP 10631B 2 metres 6 6 ft HP 10631C 4 metres 13 2 ft HP 10631D 0 5 metres 1 6 ft Cabling Restrictions 1 A Hewlett Packard Interface Bus system may contain no more than 2 metres 6 6 ft of connecting cable per instrument 2 The maximum accumulative length of connecting cable for any Hewlett Packard Interface Bus system is 20 metres 65 6 ft Figure 2 2 Hewlett Packard Interface Bus Connections m
238. ion to a value that is allowed by start and stop frequencies or set start and stop frequencies to values that allow the FM setting or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III DCFM SP117 216 LIMIT E56 4056 DC coupled FM Special Function 117 DCFM Update Mode and Special Function 216 DCFM Correction On are coupled with Special Function 123 Phase Continuous Frequency Sweep and one of those settings is limiting the selection of a frequency sweep To resolve this error either 1 turn off FM or 2 select a non dc coupled FM source or 3 turn off Special Function 117 or 4 turn on Special Function 116 DC FM Correction Off or 5 select a combination of those special functions or 6 refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III PM PREVENTS AUTO SWP E57 4057 during Stepped Frequency Sweep is only possible in manual and single sweep modes Possibly refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III AUTO SWP PREVENTS PM E58 4058 during Stepped Frequency Sweep is only possible in manual and single sweep modes Possibly refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III FREQ SWEEP PM LIMIT E59 4059 M is coupled with frequency sweep and one of those settings is limiting the
239. ions Temperature 0 to 55 C Humidity 5 to 95 maximum wet bulb temperature 40 Altitude 4570 meters 15 000 feet Airflow 5 8 mm 0 23 in minimum clearance underneath the instrument and suffi cient clearance at the instrument s right side for air flow that is not obstructed Rack Mounting The Signal Generator is heavy for its size 327 kg 71 5 lb Care must be exercised when lifting to avoid personal injury When rack mounting it is important that proper support rails are used to support the Signal Generator Additional support rail sets for HP cabi nets can be ordered under HP part number 12679B rev 20M AR85 2 5 Installation Model 8642A B Rack mounting information is provided with the rack mounting kit If the kit was not ordered with the instrument as an option it may be ordered through the nearest Hewlett Packard office For rack mount kit part numbers refer to page 1 4 paragraph 1 9 Options Available with the Instrument under Mechanical Options The Rack Slide Kit enables service personnel to slide the Signal Generator away from the cabi net and service it at the operating site Therefore if you plan to take advantage of the On Site Service Strategy for the HP 8642A B we recommend that you use the Rack Slide Kit to rack mount the instrument For instrument cabinet frames using metric hardware the HP part num ber is 08642 80059 For instrument cabinet frames using English hardware the HP part num
240. ions can also be turned off by selecting ENTRY OFF SHET CRF OFF ON 3 143 Operation Model 8642A B Knob cont d HP IB Codes 3 144 Example of Using Knob Hold To Maintain Control of a Function s Value When 1t Is No Longer Active Select Knob Hold on RF frequency x program FRKHON codes Display 34 7 I Ti 1 m Fa Fu Cu The frequency function is held on the Knob as indicated by the two cursors above the frequency value Therefore the Knob can be used to change that value even when another active function is selected Select amplitude as the active function by selecting the AMPTD key w v ATA FA FA TA TA FA FA rr 7 _ 2 nm FREQ AMPTD The cursor over the first letter of the units specifier D in DM indicates that Knob Hold has been selected on some function There is no cursor over any of the amplitude digits because the Knob is held on RF frequency which has two cursors over its setting Now turning the Knob changes frequency while selecting the Step keys or Data keys or RF OFF ON changes amplitude All this can be done without needing to select the active function s keys again KNOB INCR KNOB HOLD ON KNOB HOLD OFF ENTRY OFF Function should be preceded by an active function code Model 8642A B Operation Knob cont d Comments You Can Use the Knob to Determine Function Limits The Kn
241. ired an external LO must be provided an HP 8902A measuring receiver must be equipped with option 003 to allow this The LO must have residual FM lower than or equal to the HP 8642 SIGNAL OUTPUT GENERATOR MEASURING RECEIVER RF Figure 4 14 Residual Test Setup SYNTHES ZED SENSOR SIGNAL GENERATOR MODULE Equipment Measuring Receiver eee eet ehh sehn HP 8902A opt 003 Sensor Modules srecu eese x Le x a Bae ene tea see a eie ei ee e ren HP 11722A DO Pied E e Ee qve edu qa oor RU ee T ER ER Ede HP 8662A rev 08J UL88 Performance Test 14 4 43 Performance Tests Model 8642A B Procedure Setup 1 Connect the equipment as shown in Figure 4 14 2 Preset instruments Residual FM 1 Put the measuring receiver in FM mode using the RMS detector and enable the 50 Hz HP Filter and the 15 kHz LP Filter 2 Set the HP 8642 under test to AMPTD 10 dBm and frequencies in the following table 3 Set the measuring receiver to 500 MHz 4 Set the external LO to 1 5 MHz higher than the HP 8642 under test 5 Verify that the measuring receiver reading is less than the specified maximum Results kHz HP 8642 HP 8642 kHz dm E FREQ 10 MHz 250 MHz 0 5 GHz 1 GHz 2 GHz 4 44 Performance Test 14 rev 08J UL88 Model 8642A B Performance Tests Performance Test 15 INTERNAL TIME BASE AGING RATE TEST NOTE This test should not be performed unless Option 001 is installed Spe
242. isplay shows that the amplitude values are possible and are currently being set WwW TA TATA TAM 77 FA TI IT a ddudodudun 2 cl LI nt C Ck u nt FREQ SWPNG START AMPTD STOP The display usually shows the start amplitude and the stop amplitude settings If another active function is selected the display could indicate amplitude sweep with the SWPNG annunciator or by displaying SWEEP in the right portion of the display above the AMPTD annunciator 4 Calculate a sweep time setting that could be selected for a desired step size 4a You need to choose the step size so the amplitude span divided by the step size is an integer You must also ensure that the desired step size is between the maximum and minimum step size possible The maximum step size is equal to the maximum of 0 1 dB or Start Amplitude in dBm Stop Amplitude in dBm 5 The minimum step size is equal to 0 1 dB 4b When the sweep step size equals the minimum use a sweep time setting in ms equal to or greater than the result of the following calculation Amplitude dBm Stop Amplitude in dBm 1 8 Step Size dB d When the sweep step size is greater than the minimum use a sweep time setting greater than or equal to the result of the above calculation but less than the result of the following calculation Start Amplitude in dBm Stop Amplitude in dBm he Ga sen ads Step Si
243. itude settings are sometimes coupled with Attenuator Range Hold Special Function 9 or AM settings Therefore HP IB codes may need to be entered in a particular sequence when accessing combinations of these functions Refer to the discussion about Sequence Dependency which begins page 3 12 in the HP IB section of this Section IH 3 73 Operation Amplitude Related Special Functions Related Operating Instructions Model 8642A B cont d 4 ALC Off This special function opens the output leveling loop to provide typically a 5 dB improvement in third order intermodulation at a 2 kHz offset Typical output level accuracy is 2 dB when ALC Off is selected 204 Disable ALC Off This special function re enables the output leveling loop that was disabled with Special Function 4 9 Attenuator Range Hold On When Attenuator Range Hold is selected the Signal Generators output attenuators are fixed and the output ALC loop controls signal amplitude This produces a 30 dB range with monotonic step to step amplitude increments The upper and lower limits of each 30 dB range are determined by the Signal Generator s output amplitude when Attenuator Range Hold is selected Table 3 15 on the following page lists each 30 dB range in dBm that is available depending on the output setting when Special Function 9 is selected This table also lists the ranges at which amplitude and AM are specified which are also dependent on the ampli
244. key but the modulation oscillator can be considered off if the modulation output MOD OUT is off and no internal modulation source is in use MOD OUT How to Set Modulation Output Level The Signal Generator can be set to produce a sinewave signal at the MOD OUTPUT connector by selecting MOD OUT CSHIFT and the desired peak voltage output level in V or mV rev 23DEC86 3 131 Operation Model 8642A B Modulation Oscillator cont d HP IB Codes Comments 3 132 Example Set the Signal Generator to output a 2 Vpk 10 kHz signal at the MOD OUTPUT connector MOD OUT MOD FREQ lt gt program codes MF 10 KZ ML 2 VL Display Ti F1 T ATA Ti J l hi Lj AI C uv L Bd uh AMPTD The modulation output level has been set to 2 00V Any function which is using the modulation oscillator as a source MOD OUTPUT or internal AM FM or pulse modulation now has a rate of 10 00 KHz regardless of any previous modulation oscillator rate setting The cursor above the modulation output value indicates Modulation Output is the active function MOD FREQ MOD OUT level kHz Hz V mV SPCL Speeding Up Modulation Switching Time At instrument turn on all modulation oscillator frequency bands are characterized and given a calibration factor Modulation Frequency Calibration When the modulation oscillator frequency is set or the modulation oscillator placed in use the selected
245. l FM CW AM or Angle Modulation lt 14 Maximum Peak Deviation Post Detection Bandwidth Band 0 3 to 3 0 kHz 0 05 to 15 00 kHz 10 8642B only lt 5 Hz rms 9 Hz rms 9 2 Hz rms lt 5 Hz rms 8 1 2 Hz rms 2 Hz rms 1 7 lt 1 Hz rms 1 2 Hz rms HET lt 3 5 Hz rms lt 5 Hz rms Residual AM lt 0 01 AM rms 0 3 to 3 0 kHz Post Detection Bandwidth Spurious Output Signal 8642A B 8642B Bands 1 9 HET 10 Harmonics 30 dBc 25 dBc 20 dBc 20 dBc Sub harmonics none 45 dBc Non harmonics 100 dBc 94 dBc Output level lt 10 dBm Output level lt 16 dBm gt 10 kHz from the carrier OUTPUT Level Range From Maximum Level Available to 140 dBm 0 023 uV into 50 ohms Maximum Level Available 8642A except 8642B and Opt 003 8642A Opt 003 4 20 dBm 2 24V bands 1 thru 7 bands 1 thru 7 19 dBm 2 00V DNA band 8 18 dBm 1 78V band 8 HET HET 4 17 dBm 1 59V n a band 9 16 dBm 1 41V band 9 band 10 8642B Resolution 0 1 dB Absolute Level Accuracy 1 dB Flatness lt 0 75 dB Impedance 50 ohms nominal SWR 1 51 Output levels 0 dBm 2 0 1 Output levels 0 dBm 50W 25 Vdc 8642A 25W 50 Vdc 8642B Output levels gt 127 dBm Output level 10 dBm Reverse Power Protection Third Order Intermodulation Available Calibration Units Not specified in HET band lt 50 dBc at 10 dBm Typically decreases 10 dB for every 5 dB of combined level decrease dmb V mV
246. l internal modulation as well as for the MOD OUTPUT connector Refer to Amplitude page 3 74 for information on Attenuator Range Hold Special Function 9 This special function creates monotonic amplitude ranges that limit the specified range of AM Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed Model 8642A B Operation MODULATION FM Description The Signal Generator can frequency modulate its RF output either with a variable internal modulation oscillator and or with an ac or dc coupled external source applied to the INPUT Depending on the RF frequency selected the 8642A B has different limits on the possible FM deviation that can be selected See Figures 3 12 and 3 13 on the following page The Signal Generator normally selects a divide band to obtain its FM deviation However if the divide band s maximum internal FM deviation boundaries are crossed the Signal Generator can automatically switch to the heterodyne band which allows wider FM deviation at RF frequencies less than 132 187501 MHz Refer to RF Frequency page 3 39 for more information about these different bands If FM Pre emphasis is selected more limitations are placed on FM deviation and modulation fr
247. le via HP IB Single Sweep Selecting single sweep will start or restart a single sweep if both end points are set Single sweep initiates one sweep only at the end of the sweep the output amplitude remains at the final and point value SINGLE SHIET J STOP AMPTD HP IB code AASG The SWPNG annunciator is displayed for the duration of the single sweep The single sweep can be stopped to display the actual output amplitude by selecting manual sweep When operating the instrument locally a single sweep can also be conveniently restarted by pressing the COFF ON key twice when in the single sweep mode Start amplitude or stop amplitude must be the active function in order to use the Off On function in this way TIME How to Set Sweep Time Sweep time is set using the following procedure TIME CSHFT START FREQ and the value of the desired sweep time in s or ms MHZ or KHZ MV respectively Selecting TIME CSHFT START FREQ alone displays the current sweep time setting If sweep time is not specified the Signal Generator uses the sweep time value last entered for either frequency or amplitude sweep Note that a faster sweep time usually results in fewer steps with a larger step size The following pages contain detailed information about how to understand the relationships between sweep span sweep time step size and number of steps If you are not interested in these details you can just adjust sweep
248. led in the instrument at the time of shipment The rating of the installed fuse is selected according to the line voltage specified by the customer If the voltage is not specified the rating of the installed fuse will be selected according to the country of destination For protection against fire hazard the line fuse should only be a 250V normal blow fuse with the correct current rating Model 8642A B Installation Operating voltage is shown in module window Selection of Operating Voltage Open cover door pull the FUSE PULL lever and rotate to left Remove the fuse Remove the Line Voltage Selection Card Position the card so the line voltage appears at top left corner Push the card firmly into the slot Rotate the FUSE PULL lever to its normal position Insert a fuse of the correct value in the holder Close the cover door Figure 2 1 Line Voltage and Fuse Selection Power Cables BEFORE CONNECTING THIS INSTRUMENT the protective earth terminal of the instrument must be connected to the protective conductor 0f the mains power cord The mains plug shall only be inserted in a socket outlet provided with a protective earth contact The protective uction must not be negated by the use of an extension cord power cable without a protective conductor grounding Grounding one conductor of a two conductor outlet is not sufficient protection This instrument is equipped with a three wire power cable W
249. lent value for 1V is 13 dBm therefore 153 dB 13 dBm 140 dBm Model 8642A B Operation Relative Amplitude cont d REF SET Example 2 Configure the display to read each subsequent amplitude in dBf that is dB relative to 1 femtowatt 0 dBf 120 dBm First select INSTR PRESET to put the instrument in a known state then DATA CJ CO 2 C9 amp program APRS 120 DM codes Display b d I FA TATA FA rA rA ra imi 7 I FA FA Ti Tj idddunddd nNz cid d FREQ AMPTD REL The AMPTD REL annunciators indicate the displayed amplitude is relative to a reference amplitude The displayed amplitude is 20 0 dB dBf in this case The actual output amplitude is the displayed amplitude plus the amplitude reference therefore 20 dB 120 dBm 140 dBm REF SET How to Set a Reference to a Specific Amplitude In units of dB relative for example dBf or dBV If the output amplitude has already been set to be displayed in relative units for example dBf or dBV use the following procedure to set a specific amplitude reference CAMPTD followed by the value of the desired reference amplitude in relative dB units and REL ZERO CSHET CAMPTD REF SET Example 3 Configure the front panel to display all amplitude output values as an offset from a 20 dBf amplitude reference First set the display to read amplitude in dBf using the Relative Zero function as described in REF SET Example 2 above then p
250. mplitude Sweep AM Depth Amplitude Internal External AC Internal External DC Back Space Clear Status Byte dB or dBm dBm or dB Step Down dBuV EMF Mode Entry Off Start Frequency Sweep Stop Frequency Sweep FM Deviation Frequency GHz Help Off Help Hz Instrument Preset Increment Set Knob Hold Knob Increment Knob cursor left Knob cursor right kHz Modulation Frequency Message Modulation Output Level millisecond mV MHz Internal Output Active Function Output Parameters Changed Output Execution Error Off On Output Hardware Error Output H LO Annunciator Status 96 Pulse Deviation Partial Preset RF Off On Recall radian Relative Off Write Service Request Mask Reference Set Relative Zero Auto Sweep second Single Sweep Manual Sweep Special Function Sequence Set Sequence Sweep Time Save Step Up uM Volt External AC External DC Numerals 0 9 Decimal point Operation x Due Parmeter 3 95 3 18 3 16 3 182 3 16 3 184 3 17 3 193 3 20 3 97 3 127 3 119 3 139 3 72 3 159 3 119 3 47 3 81 3 27 3 46 3 78 3 45 3 77 3 51 3 84 3 52 3 85 3 51 3 84 3 51 3 84 3 167 3 161 3 161 3 52 3 85 3 157 3 149 3 95 3 95 lActive function code 2Function should be preceded by an active function code For example internal modulation source for AM is coded AMNT 3These codes will sometimes not need to be preceded by an active
251. mplitude setting was turned off because the new stop amplitude setting was set more than 30 dB away from the start amplitude setting This message is queued up until it is read by repeatedly selecting CMSSG amplitude sweep is turned off or the start amplitude is set again AB OFF 30DB MAX SPAN C33 2033 Stop amplitude setting was turned off because the new start amplitude setting was set more than 30 dB away from the stop amplitude setting This message is queued up until it is read by repeatedly selecting MSSG amplitude sweep is turned off or the stop amplitude is set again INCR ADJUSTED C41 2041 AMPTD REF ADJUSTED C42 2042 Increment setting adusted Amplitude reference setting adjusted Changing between EMF and non EMF amplitude modes could cause the increment and or amplitude settings to be reset to allowable values 3 183 Operation Model 8642A B Operating Messages cont d Execution Error Messages Local These messages are automatically displayed HP IB All of these messages are output via HP IB using OE Execution Error messages message code is prefixed with E describe the Signal Generator s reason for not executing an attempted setting Some settings are not possible because functions are coupled together due to limitations of internal circuit configuration This coupling will sometimes limit the execution of a setting because one function limits the setting of the other When your setting attempt cannot occur
252. ms Example for Calculation 3 Stepped Frequency Sweep In an 8642B set a stepped frequency sweep from 100 to 500 MHz with 100 frequency steps with Special Function 119 Disable Settling selected First select Special Function 1 19 SPCL C1 C1 Calculate the required sweep time setting for the 100 frequency steps using calculation 3 Maximum number of steps is equal to the minimum of 1023 or 100 000 000 Hz 500 000 000 Hz 1 Hz 400 000 000 Since 1023 is less than 400 000 000 the maximum number of steps is 1023 Minimum number of steps is equal to the minimum of 915 INTEGER oF e j or 100 000 000 Hz 500 000 000 Hz 1 Hz 400 000 000 Since 2 is less than 400 000 000 the minimum value of steps is 2 Therefore it should be possible to select 100 steps s v that value is between the minimum value 2 and maximum value 1023 Operation Model 8642A B RF Frequency Sweep cont d Example for Calculation X3 cont d To get 100 frequency steps you can set the sweep time between he resuits of the following calculations 100 1 X 80 ms 8080 ms or 8 080s 100 2 x 80 ms 8160 ms or 8 160s SWEEP START FREQ SWEEP START MH STOP 6 9 Co Co program FASA ST 8 1 SC FA 100 MZ FB 500 MZ codes These codes are not independent and might need to follow a specific sequence for entry Refer to the discussion about
253. ms sinewave input to the Signal Generator to get an actual deviation equal to the displayed deviation For example if a 1 Vpk external modulation source is provided with the Signal Generators deviation set to 50 0 radians per volt the output has 50 0 radians deviation If the source voltage is reduced to 0 5 Vpk and no other settings are changed the output has 25 0 radians deviation 3 121 Operation Model 8642A B Modulation cont d If the Hl and LO annunciators are not displayed then the external modulation signal is between 0 95 Vpk and 1 05 Vpk The HI LO annunciators only apply to sinewave inputs The HI LO detectors do not monitor dc voltage input levels External Coupling Any one of the following f ections can be used to couple the external FM M INPUT to the circuitry AC Coupled Source e EXT AC This function selects the external ac coupled M source displaying the EXT and AC annunciators INT EXT CSHET EXT AC This function selects the external ac coupled source and internal M source summed together displaying the INT EXT and AC annunciators DC Coupled Source e EXT DC This function selects the external dc coupled source for dc to 15 kHz rates displaying the EXT and DC annunciators INT EXT DC SHED EXT DC J This function selects the external dc coupled source and internal source summed together displaying th
254. n disabled with Special Function 113 Calibration typically takes one to two seconds Related Operating Instructions Refer to Modulation Oscillator page 3 131 for more information on the internal modulation oscillator that is the common source for all internal modulation as well as for the MOD OUTPUT connector Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed 3 125 Model 8642A B Operation MODULATION PULSE Description The Signal Generator can pulse modulate its RF output either with the variable internal modulation oscillator or with a dc coupled external source applied to the AM PULSE INPUT When the internal pulse modulation source is selected the pulse repetition rate can be changed by varying the modulation oscillator frequency The duty cycle will always be 50 for internal pulse modulation Table 3 23 Pulse Modulation Operating Characteristics Electrical Characteristics Performance Limits Conditions Pulse Modulation Output Levels lt 15 dBm Pulse On Off Ratio RF Frequency 1057 5 MHz RF Frequency gt 1057 5 MHz Rise Fall Time 10 to 9096 Minimum Pulse Width Maximum Repetition Frequency Nominal Peak Input Level Required Output level accura
255. n saving instrument settings that you can recall using the Sequence feature Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified 3 163 Model 8642A B Operation SPECIAL FUNCTIONS CONTENTS Figure 3 18 Special Function Related Keys 3 166 SPECIAL FUNCTIONS 3 167 HELP eet een boas Boe wawas 3 167 How to List the Descriptions of Special Functions on the Signal Generators Display eec gue e l ka 3 167 SPOL uno su a ys WAVE SE who ep Eee 3 168 How to Select Special Functions 3 168 SPCL 3 169 How to Turn Off Special Functions 3 169 How to Display the Special Functions Currently On 0 0 0 00000000 3 169 HP IB Codes ull sels Ta a 3 169 Table 3 28 Summary of Special Functions Function to Code 3 170 Summary of Special Functions Code to Function 3 171 Detailed Descriptions of All Special Functions 3s a S 3 172 3 165 Operation Model 8642A B SPECIAL FUNCTIONS 8642B SIGNAL GENERATOR 0 1 2100 MHz 0 643 EJ You can select special functions by selecting this key a C C T C print above digit keys SE NR ND The Help function enables you to display the numbers and descriptions of special functions Pressin
256. n with the REN line true low The Signal Generator processes ASCII characters individually as they are received and performs the function specified as soon as a recognizable sequence of characters has been received Accessing the Signal Generators front panel key functions via HP IB is equivalent to accessing them from the front panel Table 3 3 on the following page compares some local keystroke sequences and their corresponding HP IB code sequences Direct access to the shift functions is possible from HP IB so the Shift key is not used in HP IB coding Operation lt gt Model 8642A B Data Input cor d Sequence Dependency Table 3 3 Relationship Between Keystrokes and IB Code Sequences Function Front Panel Keystroke Sequence x Sequence To set a 1 MHz FR 1 MZ 1 W M To set an RF FRRS 1 MZ frequency reference REF SET 9 99 C 5 of 1 MHz eme eec Some functions in the 8642A B are coupled together because of internal circuit configuration limitations This coupling can limit the execution of a setting when one function limits the setting of the other For example amplitude and AM depth are coupled functions An AM depth of 99 07 is possible only when the amplitude setting is between 140 0 and 14 0 dBm Therefore changing this setting Amplitude 14 dBm AM depth 99 to this setting Amplitude 15 dBm AM depth 75 would not be possible if the amplitude entry
257. nal Generator whether addressed to listen or to talk it responds to the Local Lockout command by disabling the front panel Local key Refer to page 3 26 Clear Lockout and Set Local Regardless of the addressed state of the Signal Generator whether addressed to listen or to talk it responds to the Clear Lockout and Set Local command by re enabling the front panel Local key and returning from remote control to local control Refer to page 3 26 Require Service Regardless of the addressed state v the Signal Generator whether addressed to listen or to talk it can sena Require Service message Refer to Service Request page 3 27 Status Byte When addressed to talk after receiving the Serial Poll Enable SPE bus command the Signal Generator outputs the Status Byte Refer to page 3 29 Abort Regardless of the addressed state of the Signal Generator whether addressed to listen or to talk it responds to the Abort anc nd stops listening or talking Refer to page 3 31 HP 1B Capabilities from Local Mode Besides having the above capabilities while remote the following capabilities are also available from the local mode Require Service Status Byte Data Output 3 9 Operation Model 8642A B lt gt HP IB Capabilities cont d Table 3 1 HP IB Capability Reference Table Related Capability Applicable Response Commands and Controls cuon Data All front panel fu
258. nal with the measuring receiver The modulation output of the measuring receiver is then fed into the input of an audio analyzer and measured AUDIO ANALYZER MODULAT I ON OUTPUT SYNTHES I ZED S SIGNAL GENERATOR MODULE Figure 4 6 FM Distortion Test Setup Equipment Measuring Receiver ge s s ets casa eet etre ex gura hu a e ete ree m aie sed gs HP 8902A Sensor Module meeer err aie ure Macte V WAR Sat HP 11722A Audio Analyzer oubeibessneen gene ee ema AUR a eoe ku e sels ave en die etn n es HP 8903A 4 22 Performance Test 6 rev 08JUL88 Model 8642A B Performance Tests Procedure Setup 1 Connect the instruments as shown in Figure 4 6 and apply power 2 Preset the instruments 3 Set up the HP 8642 as follows AMPLITUDE 5 sp uQ kuyunata Seis did uyu a k NR M EI RA LT 10 dBm 4 Set up measuring receiver as follows MEASUREMENT MODE FM HP EILTER era Sa aa ie ae i Puk yu ae sea V DD EE ALL OFF LP FILTER uu ww 28s Fhe cette fo BUR NE e rewarded UE Rh I ALL OFF EM DE EMPHASIS dart e AURRI EENE D eR E E E UC weal OFF 5 Set up audio analyzer as follows MEASUREMENT MODE 0 0 ccc cece esc cece ehh e ren DISTN HP BPF FILTER e ex Re DeC E eh ALL OFF CP PILIER eer bti ere XO HAB US aa ay ia Sas ALL OFF FM Distortion Measurement 1 Set the HP 8642 to the modulation frequency RF frequency and FM deviation gi
259. nctions special functions and remote only functions are programmable except Knob L3 Rotation The Signal Generator can send status byte EO AH1 message and setting information The front panel SH1 LSTN and TLK annunciators turn on as appropriate when the instrument is addressed Trigger The Signal Generator does not have a device trigger GET DTO capability The Signal Generator responds equally to DCL and SDC bus commands The Clear capability does not re set instrument parameters Local Yes Lockout the controller or the POWER switch can return the Signal Generator to local Clear Lockout Generator returns to local and Local Lockout is no HEN RL1 Set Local longer true when the REN bus lines goes false Pass Control The Signal Generator cannot pass or take control of Take Control HP IB However it does have limited contro capability that is intended for servicing the instrument This con trol capability is accessed with Service Special Functions The Signal Generator s remote mode is enabled when the REN bus line is true However it remains in local i e the keyboard is active until it is first addressed to listen The output signal is unchanged when the Signal Generator enters the remote mode The front panel RMT annunciator turns on when in remote mode The Signal Generator returns to front panel control when it enters the local mode The output signal is unchanged Responds either to the GT
260. ncy with a loss in modulation frequency accuracy by selecting Modulation Frequency Correction Off Special Function 113 For more information refer to Speeding Up Modulation Switching Time on page 3 132 The time required to turn on the internal modulation oscillator is increased by approximately 200 ms if DC FM Update Mode Special Function 117 is active For more information refer to 117 DC FM Update Mode page 3 116 Modulation Restrictions with Other Functions AM and pulse modulation are not possible during amplitude sweep Also AM and pulse modulation are not possible when ALC Off Special Function 4 is selected Mixed Modulation The Signal Generator can simultaneously modulate the RF signal with more than one modulation type The Signal Generator does not allow simultaneous AM and pulse modulation or simultaneous FM and is allowed in the following combinations Any one of these types Internal AM e External ac or dc coupled AM or Internal external ac or dc coupled AM With any one of the following Internal FM External ac or dc coupled FM Internal external ac or dc coupled FM External low rate FM Special Function 5 Internal external low rate FM Special Function 112 Internal M External ac or dc coupled or Internal external ac or dc coupled M All internal modulation sources use the internal modulation oscillator ther
261. nd 9 Resolution 0 1 dB Absolute Level Accuracy 1 0 dB 127 dBm Flatness lt 0 75 dB 4 10 dBm 1 Includes detector linearity temperature flatness and attenuator accuracy Description Level accuracy and flatness are checked at levels that can be read accurately by a measuring receiver 10 MHz MEASURING RECE VER SYNTHES ZED SIGNAL GENERATOR SENSOR MODULE Figure 4 1 Level Accuracy and Flatness Test Setup Equipment Measuring Receiver senidea hehehe hann 8902 Sensor Module esto ve ur ess er russes era pec duse yqa AT HP 11722A rev 08J UL88 Performance Test 1 4 3 Performance Tests Model 8642A B Procedure Be sure that the calibration numbers from the power sensor module have been entered into the measuring receiver and that the measuring receiver is zeroed and calibrated in RF Power mode if the measuring receiver is an HP 8902A refer to the HP 8902A Operating Information Pull out Card RF Flatness 1 2 3 Connect the instruments as shown in Figure 4 1 Preset the instruments Set up the HP 8642 as follows AMPLITUDE red eh DER ORAS E UHR ERES KA ER CEU NER EVE 10 0 dBm Set up the measuring receiver as follows MEASUREMENT MODE RF POWER DISPLAY cog oie Reve ER PEE Ue ERR us ead Mee CET LOG dBm Set the RF frequency of the HP 8642 and the measuring receiver to those listed in
262. nd and FM To resolve this error either 1 turn off frequency sweep HP IB FAOF FBOF and then possibly select Stepped Frequency Sweep Special Function 223 or 2 select a valid sweep time setting refer to RF Frequency Sweep page 3 60 or 3 possibly turn off FM or select Special Function 208 Prefer Divide Bands or 4 refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section HI SP123 LIMITS MIN TIME E50 4050 The minimum sweep time that can be selected is limited by the currently selected combination of Phase Continuous Frequency Sweep Special Function 123 and the current start and stop frequency settings and possibly Special Function 8 Prefer Heterodyne Band and FM To resolve this error either 1 turn off frequency sweep HP IB FAOF or FBOF and then possibly select Stepped Frequency Sweep Special Function 223 or 2 select a valid sweep time setting refer to RF Frequency Sweep page 3 60 or 3 possibly turn off FM or select Special Function 208 Prefer Divide Bands or 4 refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III SP123 LIMITS MAX TIME E51 4051 The maximum sweep time that can be selected 1s limited by the currently selected combination of Phase Continuous Frequency Sweep Special Function 123 and the current start and stop frequency settings and possibly Special Function 8 Prefer He
263. nd the heterodyne band only To calculate the deviation values for the band you are using use the Divide Number column in Table 3 21 and divide that number into the Y axis deviation value For example the 1 08 MHz FM deviation limit with a 1 kHz modulation frequency would be changed to 2 16 MHz for band 10 divide by 0 5 that same limit for band 8 would be changed to 540 kHz divide by 2 and for band 7 the limit would be changed to 270 kHz divide by 4 The actual calculations used to determine deviation limits with FM pre emphasis on are as follows N is the divide number from Table 3 21 on page 3 115 MF is the modulation frequency For modulation frequencies greater than or equal to 1389 Hz the maximum FM deviation is equal to 1 5 108 1022 N VMF 45030 For modulation frequencies less than 1389 Hz the maximum FM deviation is equal to 1080 x MF 1022 N VMF 45030 Table 3 20 page 3 112 lists FM deviation limits with an external source HP IB When using FM pre emphasis HP IB codes may need to be entered in a particular sequence Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III 206 Pre emphasis Off This special function turns off the pre emphasis that 15 selected with Special Function 6 3 113 Operation Model 8642A B Modulation FM cont d 1k 1389 MODULATION FREQUENCY Hz pou SEE ie
264. ne COE ER Dh d e e TR HP 8566A Procedure 1 Perform a center frequency calibration on the spectrum analyzer 2 Connect the instruments as shown in Figure 4 9 3 Preset the instruments 4 Set up the spectrum analyzer as follows SPAN aquta u Supaya E epe See eae a ed 0 kHz RESOLUTION BANDWIDTH ueeeeeeeee hh hh hn 10 Hz 5 Set the 8642 s frequency and amplitude to values listed in the following table Set the Spectrum Analyzer s reference level and frequency to the values given in the following table 6 All spurious signals must be below the level stated in the following table rev 08JUL88 Performance Test 9 4 31 Performance Tests 4 32 NOTE In order to obtain maximum sensitivity this test requires driving the input mixer of the spectrum analyzer above its optimum level This could cause the generation of spurious signals in the spectrum analyzer If a spurious signal is observed change the 8642 s frequency If the spurious disappears it most likely is from the HP 8642 If the spurious moves with the 8642 s signal it is probably generated in the spectrum analyzer Spectrum Analyzer Analyzer Results Results dBm AMPTD CENTER FREQ Ref Level dBm MHz dBm Performance Test 9 4 130 000 4 130 000 4 130 000 4 130 000 4 130 000 4 130 000 4 130 000 90 000 000 600 000 000 600 000 000 571 144 000 610 519 000 745 951 000 775 184 000 780 184 000 797 878 000 96
265. ne simultaneously with M PHASE MOD TURNED OFF C13 2013 was turned off FM was selected when was on cannot be done simultaneously with FM PULSE MOD TURNED OFF C14 2014 Pulse modulation was turned off Either START AMPTD J STOP AMPTD or CAM was selected HP IB codes AA AB or AM when pulse modulation was on Pulse modulation is not possible when amplitude sweep or AM are on 3 182 Model 8642A B Operation Operating Messages cont d SWEEP TIME ADJUSTED C21 2021 Sweep time was adjusted to the minimum allowed setting The sweep time setting was less than the minimum allowed for the type of sweep selected Either a Stepped Frequency Sweep was set with the sweep time set less than 275 ms or amplitude sweep was set with the sweep time set less than 20 ms FREQ SWEEP TURNED OFF C22 2022 RF frequency sweep was turned off Either FREQ CSTART AMPTD or STOP AMPTD was selected HP IB codes FR AA AB when RF frequency sweep was on FR SWP AM TURNED OFF C23 2023 RF frequency sweep and AM were turned off Either START AMPTD or STOP AMPTD was selected HP IB codes AA AB when RF frequency sweep was on with AM AMPTD SWP TURNED OFF C31 2031 Amplitude sweep was turned off One of the following functions was selected when amplitude sweep was on START FREQ J STOP FREQ AMPTD J CAM or PULSE CSHET CAM HP IB codes FA FB AP AM PL AA OFF 30DB MAX SPAN C32 2032 Start a
266. ning to local control in this way has the following disadvantages 1 It defeats the purpose and advantages of local lockout that is the system controller will lose control of a system element 2 Instrument configuration is reset to the power up conditions listed in the Detailed Operating Instruction Instrument Preset Partial Preset page 3 137 Model 8642A B Operation Overview RQS MASK Clearing the x SERVICE REQUEST The Signal Generator uses its internal Status Byte and a Request Service Mask Byte RQS mask that you set to determine whether to issue a Service Request SRQ bus line true The RQS mask is an 8 bit byte that you can set to define which bits of the Status Byte will be allowed to cause a service request See Figure 3 4 on the following page Bits O through 5 and 7 of the Status Byte are logically ANDed with bits 0 through 5 and 7 of the RQS mask byte If the resultant value is not equal to zero the Signal Generator sets bit 6 of the Status Byte true which sends a Service Request SRQ message to the system controller SRQ bus line true At turn on or instrument preset the RQS mask byte is set to zero effectively disabling or masking all the status bits from causing a service request message Changing the 8 bit RQS Mask Byte From the Remote Mode Send RM the decimal equivalent of the binary 8 bit byte a number between 0 and 255 and the terminator HZ From the Local Mode Select ROS MASK
267. nique allows improved modulation characteristics and wider sweep spans for Phase Continuous Frequency Sweep Table 3 11 RF Frequency Band Ranges Carrier Frequency MHz Divide Number 10 1057 500001 to 2115 000000 8642B only 528 750001 to 1057 500000 9 264 375001 to 528 750000 132 187501 to 264 375000 66 093751 to 132 187500 33 046876 to 66 093750 16 523438 to 33 046875 8 261719 to 16 523437 4 130860 to 8 261718 0 100000 to 4 130859 0 100000 to 132 187500 m Q O Ir 4 Operation Model 8642A B RF Frequency cont d Procedure FREQ The divide bands and the Het band have the following advantages Divide Bands Het Band Lower phase noise Greater stereo separation with Higher output level dc coupled FM specifications Wider FM 9 M deviation at frequencies less than 132 187501 MHz Greater AM rates in the range from 4 130860 to 33 046875 MEZ Wider frequency spans in Phase Continuous Frequency Sweep Special Function 123 Refer to Table 1 1 Specifications which starts on page 1 7 for the specific differences between the Het band and the divide bands The divide bands are normally selected since they have the lowest possible phase noise However the Signal Generator will automatically switch to or from the Het band if a setting crosses either a divide band s maximum FM or deviation limits or a divide band s frequency span limits in Phase Continuous Frequen
268. nits Refer to page 3 205 for amplitude units conversion information to determine amplitude sweep start and stop end points in absolute units Refer to Amplitude page 3 69 for additional information about setting amplitude Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Instrument Preset Partial Preset page 3 139 for information on setting the intrument to an initialized state that maintains preset references including the selected amplitude units Refer to Operating Messages page 5 177 if the instrument displays a message you want clarified Model 8642 Operation AMPLITUDE SWEEP Description The Signal Generator can amplitude sweep between a start end point and a stop end point in linearly spaced incremental steps Sweep step size is automatically selected based on the amplitude span which is the absolute value of the start amplitude minus the stop amplitude and the sweep time Although step size cannot be directly set this operating instruction provides ways to calculate a sweep time to enable you to select a particular step size or number of steps Table 3 16 Amplitude Sweep Operating Characteristics Electrical Performance Characteristics Limits Output Amplitude Sweep Range 20 dB logarithmic 20 dB linear with Special Function 122 Sweep Time 20 ms minimum 999s maximum Accuracy 1 dB Over highest 10 dB of amplitude range 3 dB
269. nother active function is selected the display could indicate amplitude sweep with the SWPNG annunciator or by displaying SWEEP in the right portion of the display above the AMPTD annunciator To actually see the 0 8 dB steps on the display you can select manual sweep and turn the Knob slowly or use the Step keys Operation Model 8642A B Amplitude Sweep cont d HP IB Codes Comments 3 92 START AMPTD STOP AMPTD SWEEP TIME AUTO MANUAL SINGLE OFF ON AAOF ABOF AAON ABON Sweep Time Is Common to All Sweeps Sweep time is common to amplitude sweep and frequency sweep If sweep time is not specified the Signal Generator assumes the value last selected for either amplitude or frequency sweep If this last selected sweep time value is below the minimum setting allowed under current conditions the message SWEEP TIME ADJUSTED 21 is displayed and sweep time is automatically set to the minimum allowed setting Changing End Point Values During the Sweep During auto or single sweep the Knob Step keys and Data keys can be used to change the start and stop end points and sweep time values During manual sweep the Knob and Step keys can only be used to perform the manual sweep HP IB How to Manually Sweep In the manual sweep mode HP IB codes UP and DN can be used to step manually by one step each time the code is sent Knob rotation is not possible via HP IB How to Tell if the Start and Stop Amplitude Entries
270. nthesized Signal Generator Operation and Calibration Manual Manual Part Number 08642 90224 Revision Date 1996 03 01 HP References in this Manual This manual may contain references to HP or Hewlett Packard Please note that Hewlett Packard s former test and measurement semiconductor products and chemical analysis businesses are now part of Agilent Technologies We have made no changes to this manual copy The HP XXXX referred to in this document is now the Agilent XXXX For example model number HP8648A is now model number Agilent 8648A About this Manual We ve added this manual to the Agilent website in an effort to help you support your product This manual provides the best information we could find It may be incomplete or contain dated information and the scan quality may not be ideal If we find a better copy in the future we will add it to the Agilent website Support for Your Product Agilent no longer sells or supports this product You will find any other available product information on the Agilent Test amp Measurement website www tm agilent com Search for the model number of this product and the resulting product page will guide you to any available information Our service centers may be able to perform calibration if no repair parts are needed but no other support from Agilent is available Ae Agilent Technologies HP 8642A B SYNTHESIZED SIGNAL GENERATOR Including Options 001 002 and 003 Operation
271. nuators Refer to Table 3 14 below The amplitude portion of the display reads RF OFF Table 3 14 RF OFF Output Amplitude Levels Output Harmonic RF Frequency MHz Signal Attenuation Attenuation dB dB 1057 500001 to 2115 000000 528 750001 to 1057 500000 0 100000 to 528 750000 except Heterodyne Band 0 100000 to 132 187500 Heterodyne Band Only EMON EMOF APOF APON RF OFF ON RO R1 SPCL SP Overranging Specified Amplitude Amplitudes as high as 20 dBm 2 24V 127 0 dBuV 4 49 EMF V or 133 0 dB uv can be set at any RF frequency setting but the level is not specified above the values listed in Table 3 13 on page 3 69 Model 8642A B Operation Amplitude cont d Depending on combinations of settings selected for amplitude and frequency and or AM that overrange specified amplitude levels a message may occur indicating an automatic leveling control ALC loop out of lock condition However the ALC loop out of lock condition requires continuous microprocessor action that results in a slight increase in noise spurious signals and Radio Frequency Interference RFI To eliminate these noise levels either turn the ALC loop off Special Function 4 or eliminate the overrange condition Refer to on page 3 197 for more information about these out of lock messages Resolution is in dB When Setting Voltage Levels Select voltage levels with a resolution as small as 0 001 uV 0 002 EMF However intern
272. ob can be used to determine the approximate limits for all function settings However the limits reached with the Knob will not cause the Signal Generator to display a message describing the reason for the limitation Use a Data entry beyond the limitation to cause the Signal Generator to describe a limitation Undisplayed Digits May Appear to Affect Maximum Settings You can step in increment set values that will not be displayed when the resolution of the current setting is coarser than the increment set value For example with FM deviation set to 1 30 MHz an increment change of 1 kHz will not be displayed until 10 increments have been stepped Consequently if at any time you step the displayed setting by that undisplayed increment setting and then turn the Knob the Signal Generator may seem to not be able to reach its maximum value For example stepping from 1 300 MHz displayed value of 1 30 MHz to 1 301 MHz displayed value 1 30 MHZ and turning the Knob will only allow a maximum displayed value of 1 49 MHz since the maximum possible deviation is 1 500 not 1 501 MHz Partial Preset Does Not Change Increment Set Values Select PARTIAL INSTR PRESET to put the instrument in a known state without resetting increment set values How Fast You Turn the Knob Affects the Knob Sensitivity Knob sensitivity changes from fine to coarse when Knob rotation is changed from slow to fast unless Knob Increment is in use HP IB
273. ode from the front panel in the same way you turned it on EMF CSHFT SET OFF ON HP IB code EMOF Example Turn on the EMF mode program codes The EMF mode has been activated as indicated by the EMF annunciator Until this mode is turned off subsequent amplitude entries will be in EMF units Now set the amplitude to 2 3 EMF uV DATA JC 06 0 x program codes AP 2 3 UV Display DII Papa Amplitude has been set to 2 3 EMF uV The cursor above the amplitude display setting indicates amplitude is the active function Operation Model 8642A B Amplitude cont d AMPTD OFF ON RF OFF ON How to Turn Off the Amplitude Output HP IB Codes Comments The RF output can be turned off using the following method By selecting the OFF ON key when amplitude is the active function HP IB APOF The amplitude display will read AP OFF When amplitude is turned off in this way the RF output and all harmonics subharmonics and all other spurs will be reduced to a level below 140 0 dBm 0 023 uv 0 046 EMF uV 33 0 dBuV or 27 0 dB EMF uv By selecting RE OFF ON Amplitude will be toggled off or on each time this key is selected Amplitude does not have to be the active function to reduce RF output amplitude with the RE OFF ON key This function reduces the level of the carrier frequency and associated harmonics without adjusting the output atte
274. oise level 9 The actual phase noise is calculated from the reading obtained in step 6 by applying the following corrections a Subtract the reading from step 4 to convert the reading to units of dBc b Add 63 5 dB 50 dB for HP 8642 attenuator change 10 dB for 1 Hz bandwidth normalization 6 dB for single side band conversion 2 5 dB to correct for the Log shaping and average detection 10 Phase noise should be 125 dBc or lower dBc rev 08JUL88 Performance Test 11 4 37 Performance Tests Model 8642A B Performance Test 12 SSB PHASE NOISE TEST OPTIONAL Specification Performance Limits Electrical Characteristics Conditions 20 kHz Offset 200 kHz Offset Residual SSB Phase 125 dBc 134 dBc band 10 Noise in 1 Hz 134 dBc 143 dBc band 9 Bandwidth 137 dBc 144 dBc band 8 141 dBc 144 band 7 144 dBc 145 dBc band 6 145 dBc 145 dBc band 5 146 dBc 147 dBc band 4 147 dBc 148 dBc band 3 148 dBc 149 dBc band 2 137 138 dBc band 1 125 dBc 137 dBc band HET Description This test is an alternative to Performance Test 11 This test should be performed only if it is necessary to check phase noise at frequencies other than 10 MHz An LO and a double balanced mixer are used to translate the noise spectrum to a lower frequency so that it can be viewed on a high resolution spectrum analyzer NOTE This test measures the total SSB
275. ompt Messages Local These messages are automatically displayed when you execute a function HP IB Most of these messages can be output via HP IB using the Output Display capability after you execute a function P91 cannot be read via HP IB Prompt messages message code 15 prefixed with P instruct you towards completion of the task or function selection you began SPCLS OFF ENTER NUMBER PO All special functions are off To select a special function select its number HIT MSSG FOR EACH MSSG Pl 1501 More than one message is in the message list select MSSG HP IB code MG to see each message HP IB Note that when retrieving a message list using the OH command when more than one message exists this is the first message you will receive in the list Refer to the Output Messages discussion that begins on page 3 17 in the HP IB portion of this Section For information about re reading the copied message list refer to Queued Up Messages on page 2 180 OFF ON SELECTS EMF ON P2 The EMF mode is off Select ON HP IB EMON to select EMF on OFF ON SELECTS EMF OFF The mode is on Select OFF ON HP IB EMOF select off HIT OFF ON HOLD FUNC PA Knob Hold is off to hold the active function on the Knob select COFF ON HP IB Send the HP IB code of the desired active function followed by KHON HIT OFF ON HOLD OFF P5 Knob Hold is on to turn off the Knob Hold function select OFF ON
276. on Model 8642A B Modulation cont d Related Special Functions 3 124 Selecting Heterodyne Band Operation Special Function 8 Prefer Het Band can be used to cause the Signal Generator to oper ate in the heterodyne band regardless of M deviation whenever RF frequeucy is less than 132 187501 MHz This function prevents the Signal Generator from switching from the heterodyne band when it would be possible to use the divide bands Refer to How to Select the Het Band on page 3 41 Mixed Modulation The Signal Generator can simultaneously modulate the RF signal with more than one modulation type The Signal Generator does not allow simultaneous AM and pulse modulation or FM and is allowed in the following combinations Any one of these types Internal External ac or dc coupled M or Internal external ac or dc coupled With any one of the following Internal AM External ac or dc coupled AM Internal external ac or dc coupled AM Internal pulse modulation or External dc coupled pulse modulation All internal modulation sources use the internal modulation oscilator therefore all internal modulation as well as MOD OUTPUT have the same modulation frequency Spurious Signals Spurs That Occur with the Internal Source Internally generated spurs with levels specified less than 100 dBc might be present when the internal modulation oscillator i
277. on code Considerations When Using Increment Set with Amplitude Settings If amplitude is displayed in dBm and increment size is in volts the setting will change by the dB equivalent of the voltage increment Similarly if amplitude is displayed in volts and the increment setting is in dB the amplitude setting will change by the voltage equivalent of the dB increment 0 001 uV to 2 24V 0 002 EMF uV to 4 49 EMF V increments can be selected However the Signal Generator s setting resolution is limited to the voltage equivalent of 0 1 dB at every output level except during Linear Amplitude Sweep Special Function 121 Model 8642A B Operation Step Increment Set Related Operating Instructions Undisplayed Digits May Appear to Affect Maximum Settings You can step in increment set values that will not be displayed when the resolution of the current setting is coarser than the increment set value For example with FM deviation set to 1 30 MHz an increment change of 1 kHz will not be displayed until 10 increments have been stepped Consequently if at any time you step the displayed setting by that undisplayed increment setting and then turn the Knob the Signal Generator may seem to not be able to reach its maximum value For example stepping from 1 300 MHz displayed value of 1 30 MHz to 1 301 MHz displayed value 1 30 MHz and turning the Knob will only allow a maximum displayed value of 1 49 MHz since the maximum poss
278. on frequency is not monitored by the Signal Generator when an external modulation source is used The cursor above the AM setting indicates AM 18 the active function The LO annunciator may be indicating that the external modulation source is at a dc level all inputs appear as LO or that there is a sinewave input less than 1 volt INT EXT DC MOD FREQ OFF ON AMOF AMON INT 96 PC EXT AC kHz EXT DC Hz INT EXT AC SPCL Model 8642A B Operation Modulation AM cont d Comments Specified AM Rates Can Be Increased by Selecting the Het Band AM depths are specified for depths less than or equal to 90 at a maximum rate of 20 kHz in bands 2 3 and 4 4 130860 to 33 046875 MHz You can increase specified AM rates in this RF frequency range from a maximum of 20 kHz to a maximum of 100 kHz by selecting Special Function 8 Prefer Het Band Refer to How to Select the Het Band on page 3 41 Spurious Signals Spurs That Occur With the Internal Source Internally generated spurs with levels specified less than 100 dBc might be present when the internal modulation oscillator is 1n use These spurs will be eliminated when no internal modulation source is modulating the carrier and the modulation oscillator MOD OUT is off Modulation Switching Time The time required to turn on the internal modulation oscillator or to switch between modulation frequencies can be reduced by approximately 200 ms depending on modulation freque
279. or 8642B only The measuring receiver s reading must be less than 0 02 at these frequencies If the reading is too high it means the residual AM of the measuring receiver or possibly of the HP 8642 is too high to make the incidental AM measurement Determine the cause of the high residual AM before proceeding If the reading is less than 0 02 set the HP 8642 to FM to 20 kHz deviation and modulation frequency to 1 kHz 3 Set the HP 8642 frequency to the settings in the table below and verify that the measuring receiver readings are less than the specified maximum FM Distortion 1 kHz Preset the instruments Set the measuring receiver to FM mode and audio distortion mode Turn off all audio filters Set the HP 8642 amplitude to 10 dBm Set the HP 8642 RF frequency and FM deviation to the values listed in the table below ao N Verify that the measuring receiver readings are less than the specified maximum o med Actual Distortion NN 1050 72 0 0 4 256 135 0 2 0 67 5 4 0 reu 08J UL88 Performance Test 5 4 21 Performance Tests Model 8642A B Performance Test 6 EXTENDED FM DISTORTION TEST Specification Electrical Characteristics Performance Limits FREQUENCY MODULATION FM Distortion 1 15 max dc coupled deviation 20 Hz to 100 kHz 1 2 max dc coupled deviation max dc coupled deviation Description All FM distortion specifications are checked by demodulating the sig
280. or sweep mode off Reset with an Output Hardware Error message to the 8642A B HP IB program code OH More than one Hardware Error message may be present After OH is executed one error message code or string is out put with each address to talk The Detailed Operating Instruction Messages lists the error codes with their respective messages To properly retrieve all Hardware Error information re fer to the example program in Data Output in this HP IB information section Reset with an Output Execution error message to the 8642 HP IB program code OE Error code that caused bit to be set can be determined by reading the Output Execution Error code or string Refer to the ex ample program in Data Output in this HP IB informa tion section Reset when remote Can be used to detect a front panel SRQ emulated by selecting the LOCAL key if not in Local Lockout The Status Byte must actually be read with this bit set for the instrument to have completed the processor delay time part of the setting change which might not include the analog settling time Reset when bits 1 and 2 are reset Reset when the RQS mask ANDed with the Status Byte ignoring bit 6 equals O Reset with an output Parameter Changed message HP IB program code OC Parameter that was changed can be determined by transmitting the Output Parameter Changed message code or string Refer to the example program in Data Output in this
281. or dB EMF uV to EMF uV Observe the following three considerations sequentially when converting amplitude units 1 When you desire non EMF units and the EMF mode is currently selected turn off the EMF mode by selecting EMF CSHIET NCR SET CFF ON HP IB code EMOF If you desire EMF units then do nothing at this point 2 Use the following table to determine the keystrokes or HP IB codes that will convert to the amplitude units in the left column of the table To Select The Select the Following Units or 692 5 CJ CO CO G2 V REF SET dB EMF V C GJ APRS 1 VL SE C eQ APRS 1 MV dB REL dB REL Refer to Relative Amplitude EMEN 1if operating below 127 0 dBm up to a 0 2 dB change could occur To ensure no level change occurs use the second sequence provided or To ensure that message AMPTD REF SET to 1 00UV C2 will not occur use the second sequence provided 3 When you desire EMF units and the EMF mode is currently off turn on the EMF mode by selecting EMF SET OFF ON HP IB code EMON rev 20MAR 85 3 205 Appendix C Model 8642A B Appendix C Amplitude Units Conversion cont d To convert amplitude values manually use the following conversion formulas dBm dBm dBf dBm 120 0 dB V dBm 13 0 dB mV dBm 47 0 dB uV dBm 107 0 dB EMF V dBm 7 0 dBEMFmV dBm
282. or information about the way these are accessed Model 8642A B MODULATION CONTENTS Figure 3 11 Modulation Related Functions 3 96 MODULATION AM 3 97 c AVE 3 97 Table 3 17 AM Operating Characteristics 3 97 INT Zuma s pipa mi sa k o obe tee A Sua ees e 3 98 How to Set AM with the Internal Source Using the Modulation Oscillator 3 98 EXT AC EXT DC 3 98 How to Set AM with an External Source 3 98 HP IB Codes 3 100 Comments sees nn 3 101 Table 3 18 Limitations on AM Settings With Amplitude 0 0 00 0 000 002 cece sese 3 102 Related Special Functions 3 104 113 Modulation Frequency Correction Off 3 104 248 Calibrate the Modulation Frequency Bands 3 104 MODULATION FM 3 105 FM he et ord eae enn i TM aL 3 105 Table 3 19 FM Operating Characteristics 3 105 Figure 3 12 FM Deviation Limitations for each RF Frequency Band Modulation Frequencies lt 1389 2 A Ske Mae ea 3 106 Figure 3 13 FM Deviation Limitations for each RF Frequency Band Modulation Frequencies 21389 HZ rA RARE utt E Yu 3 106 INT teer eb E RO ren p 3 107 How to Set FM with the Internal Source Using the Modulation Oscillator 3 107 EXT AG EXT DC 3 108 How to Set FM wi
283. ou can access a shift key function by first pressing the blue SHIFT key which causes the display to show SHIFT and then the key under the blue label In these instructions we show the shift key function s blue label in capital letters for example REF SET followed by the actual key you need to press to access that function That is we would show REF SET CSHET FREQ Special Functions You can turn on a special function by pressing SPCL J then by keying in the code number of the desired special function After you select a special function its code and description are displayed You can clear this message from the display by pressing the SHIFT key twice Procedures The Procedures provide examples to show you how to operate the function or functions explained in the Description Before each example we instruct you to select Instrument Preset to put the Signal Generator in a known state so that your instrument will display identical settings as in the display portion of our examples HP IB Codes All HP IB codes relevant to that operating instruction are listed Comments The Comments add extra information about the function s that might be valuable Reiated Special Functions The Related Special Functions list and describe some special functions that might apply to the main function Related Operating Instructions This listing refers you anywhere else in the Detailed Operating Instructions t
284. p rev 08JUL88 Performance Test 8 4 27 Performance Tests Model 8642A B Equipment Measuring Receiver a rensvrerectpexesu lane ae V e pP ULCUS HP 8902A Sensor Module esce p sut peek easy pet aae Ie HP 11722A SWR Bridge ayunaq de ied aa SER Uem apu Pepe eds Wiltron 60NF50 Type N ShoEb 3 205 ae tes tM eth CR RE deoa shu usuyasa uu mayt PEDE HP 11512A Signal Generator s web e Re iR Bade dew pe a eee a eat HP 8642B Procedure High Level SWR Calibration 1 1 Connect the instruments as shown in Figure 4 8 Setup A a Preset the instruments b Set up the measuring receiver as follows MEASUREMENT MODE RF POWER DISPLAY Sr raa utr ebd ek Eder I Ee Ne a Aw TVA LOG c Set up the HP 8642 as follows AMPLITUDE INCREMENT 0 1 dB 2 Set the HP 8642 and the signal generator to the frequency listed in the table on the next page 3 Set the signal generator level to 80 dBm 4 Set the HP 8642 level as listed in the table on the next page Make a reading on the measuring receiver and record it in the table on the next page Cal 1 Reading Repeat this step for all frequencies in the table Calibration 2 1 Connect the instruments as shown in Figure 4 8 Setup B a Preset the instruments b Set up the measuring receiver as follows MEASUREMENT MODE
285. p Calculations Since the sweep step size is not directly selectable the following calculations provide ways to determine 1 the number of steps automatically selected page 3 53 2 the frequency step size automatically selected page 3 54 3 the required sweep time that will select a desired number of frequency steps page 3 54 and 4 the required sweep time that will select a desired step size page 3 57 However these calculations do not directly apply to situations when the start end point is equal to the stop end point zero span Refer to Zero Span for Stepped Frequency Sweep on page 3 64 for information about X axis steps in zero span The minimum frequency dwell time per point is different depending on whether you have an 8642A or 8642B and whether you have selected Special Function 119 So whenever you see the term Min Dwell Time in a calculation use the table above that lists the Minimum Frequency Dwell Time Per Point to determine the value of that term Also frequency points are truncated to 1 Hz Span is always an integer since end points are integers 1 Calculate the number of steps automatically selected The number of steps is the minimum of 1023 or Start Frequency in Hz Stop Frequency in Hz or Sweep Time in ms INTEGER OF Min Dwell Time in ms Operation Model 8642A B RE Frequency Sweep cont d 2 Calculate the sweep step size automatically selected The r
286. pecial Functions 653 through 659 manipulate message 1 Special Functions 663 through 669 manipulate message 2 Note that accessing service special functions is different than accessing the user special functions discussed previously in this manual To select user special functions you key in SPCL CSHIFT and then the special function number For HP IB use the example on page 3 202 To select service special functions locally you need to follow two steps 1 First select user Special Function 3 Service Mode with keystrokes SPCL CSHIFT ZJ Once you enter the service mode you can access the actual service special functions However you can only key in numbers and terminators selecting any other key will cause the instrument to exit this special mode and display current instrument settings 2 After you enter the service mode you can select the service special function number However the instrument only knows that you have selected a special function when you key in the HZ UV terminator For example to clear the current message in message 1 you would key in 6 C CS CHZ UV Table 3 30 on page 3 203 lists the special functions that apply to both message 1 and message 2 Table 3 31 on page 3 203 provides a list of valid ASCII character codes Page 3 204 lists messages that might appear when manipulating the user defined messages Example of Entering a User Defined Message Via the Front Panel Keys Select the keys
287. put amplitude HP IB AP to the desired level before selecting attenuator range hold HP IB SP9 SP9 PREVENTS SP4 E80 4080 Special Function 4 ALC Off is not possible when Special Function 9 Attenuator Range Hold is selected Select Attenuator Range Hold Off Special Function 209 before selecting ALC off HP IB Send SP209 before SP4 SP4 PREVENTS SP9 E81 4081 Special Function 9 Attenuator Range Hold is not possible when Special Function 4 ALC Off is selected Disable ALC Off Special Function 204 before selecting attenuator range hold HP IB Send SP204 before 5 9 AM PREVENTS SP4 E82 4082 Special Function 4 ALC Off is not possible when AM is selected Turn off AM before selecting ALC off HP IB Send AMOF before SP4 PULSE PREVENTS SP4 E83 4083 Special Function 4 ALC Off is not possible when pulse modulation is selected Turn off pulse modulation before selecting ALC off HP IB Send PLOF before SP4 rev 20MAR 85 3 191 Operation Model 8642A B Operating Messages cont d SP4 PREVENTS AM E84 4084 AM is not possible when Special Function 4 ALC Off is selected Select Disable ALC Off Special Function 204 before setting AM HP IB Send SP204 before AM SP4 PREVENTS PULSE E85 4085 Pulse modulation is not possible when Special Function 4 ALC Off is selected Select Disable ALC Off Special Function 204 before selecting pulse modulation HP IB Send SP204 before PL INVALID SPCL FUNCTION E86 4086 An
288. put are being reset This time is called start of sweep settling time Start of sweep settling time is not included in the sweep time setting Also start of sweep settling time is not selectable For Stepped Frequency Sweep this settling time is approximately 12 of sweep time with a minimum of 100 ms and a maximum of 600 ms this time can be reduced by approximately half when you select Special Function 119 Disable Settling Normally for Phase Continuous Frequency Sweep the settling time is approximately 12 of the sweep time However for sweep times less than 75 ms the settling time can be equal to or slightly greater than the sweep time itself depending on the sweep span For sweep times greater than 75 ms the settling time gradually approaches 12 of the sweep time Minimum settling time is 15 ms maximum settling time is S00 ms HP IB Sequence Dependency RF frequency sweep settings are sometimes coupled with other functions Therefore HP IB codes may need to be entered in a particular sequence when accessing combinations of these functions Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section 3 65 Operation Model 8642A B RF Frequency Sweep cont d Related Special Functions Related Operating Instructions 3 66 119 Disable Settling This special function allows the Signal Generator s microprocessor to respond to new commands without waiting fo
289. quest service 1s from the Signal Generator s point of view The request service RQS bit is in the 8642A B Status Byte This bit affects when the service request SRQ line is pulled on the HP IB interface Refer to page 3 27 scroll Scrolling through the Help function list lets you view the description and code number of each Special Function Refer to the Special Functions page 3 167 You can scroll through the message list by repeatedly selecting the MSSG key SRQ SRQ is from the HP IB controller s point of view The service request SRQ line is a signal line on the HP IB interface This line is pulled low by the Signal Generator when it is requesting service Refer to page 3 27 The SRQ annunciator in the display of the 8642A B indicates that this Signal Generator is pulling the HP IB SRQ line low 3 200 Model 8642A B Appendix B Appendix B WRITING MESSAGES TO THE DISPLAY You can write messages to the Signal Generator s display using service special functions and ASCH character codes Two separate 49 character message strings can be easily displayed on the front panel or read via HP IB Messages such as these could be useful for example when keeping track of calibration times or the owner of the instrument or special calibration information Also when testing instruments a message could be used as a system prompt These messages are battery backed up and can be stored through power off to be read any time Service S
290. r Values of FM deviation are for the RF frequency Band 9 528 750001 1057 500000 MHz and the Heterodyne Band c z E e gt L z 8 s 3 2 E 5 s 2 iti 53 255 S F iH ii Sue iii fis 2 353 2 5 E gt i i 552 irn HE i 25 i f i 2 i s f i i z P z a I 1 1 HE Hi ii P PI v z 5 2 gt 5 i H i 1 i E e FM DEVIATION Hz Figure 3 14 FM Devation Limits with without FM Pre emphasis 3 114 rev 05MAY89 Model 8642A B Operation Modulation FM cont d Table 3 21 Factor for Y Axis FM Deviation Quotient RF Frequency Range Divide Number 1057 500001 to 2115 000000 8642B only 528 750001 to 1057 500000 264 375001 to 528 750000 132 187501 to 264 375000 66 093751 to 132 187500 33 046876 to 66 093750 16 523438 33 046875 8 261719 to 16 523437 4 130860 to 8 261718 0 100000 to 4 130859 0 100000 to 132 187500 E e 9 8 7 6 5 4 3 2 1 7 Low Distortion FM M On This special function switches shaper circuitry into the FM M loop reducing total harmonic distortion With Special Function 7 total harmonic distortion is typically less than 0 03 for FM deviations less than 7 of maximum deviation For example if operating at 9
291. r the internal circuitry to settle When using this special function it s possible to select a function before the previous function has finished settling When settling is disabled response time is improved by up to 40 ms Special Function 119 disables out of lock messages 219 Re enable Settling This special function re enables the settling that is disabled when Special Function 119 is selected 121 Sweep Up and Down On During auto or single sweep modes the Signal Generator sweeps from the start end point to the stop end point and then sweeps from the stop end point to the start end point in the same amount of time See Figure 3 7 below for a comparison of the normal sweep mode Sweep Up and Down Off Special Function 221 and the up and down sweep mode Sweep Up and Down On Special Function 121 The waveforms are not drawn to scale There is no start of sweep settling time when this special function is selected Also Z AXIS is always a TTL low 221 Sweep Up and Down Off This special function re enables the normal sweep disabled with Special Function 121 Special Function 221 sets the Signal Generator to sweep from the start end point to the stop end point and then again from the start end point to the stop end point NORMAL SWEEP MODE UP AND DOWN SWEEP MODE E 2 2 n a 2 2 o o O m gt gt lt lt 1 1 gt x Figure 3 7 Sweep Waveforms Refer to RF Frequency page 3 39 for additional information that
292. rce HP IB Send only PLNT or PLXD or ensure codes AM FM or PM are sent before XA BA or BD PULSE MOD ONLY OFF ON E27 4027 Pulse modulation can only be off or on Since pulse modulation can only be turned off or on knob rotation cursor positioning keys and Step keys cannot affect the pulse modulation function HP IB Select a function code before UP DN KL or KR AM PREVENTS PULSE MOD E28 4028 AM is not possible with pulse modulation Turn off AM HP IB AMOF before selecting pulse modulation PULSE MOD PREVENTS AM E29 4029 Pulse modulation is not possible with AM Turn off pulse modulation HP IB PLOF before selecting AM TURN OFF EMF FOR DBM E30 4030 When in the EMF mode dBm units are not possible Turn off EMF before selecting dBm amplitude units NO RELATIVE AMPTD SWP E31 4031 Relative values for amplitude sweep cannot be set directly Convert the desired relative setting value to absolute units then set the amplitude sweep in absolute units Refer to page 3 205 for amplitude units conversion information Select only FREQ or AMPTD HP IB code FR or AP before attempting relative settings 3 186 Model 8642A B Operation Operating Messages cont d NO RELATIVE FREQ SWP E32 4032 Relative values for frequency sweep are not possible Select only FREQ J or AMPTD HP IB FR AP before attempting relative settings ONLY FREQ AMPTD REL E33 4033 No relative units are possible with the requested
293. re YY is the last two digits of the year MM is the number of the month and DD is the day of the month For example 841225 would be December 25 1984 250 Phase Adjustment from Knob and Step Up and Step Down Keys This function enables control over the RF signal s output phase in one degree steps using either the Knob or Step keys 251 Clear Recall Registers This special function clears all recall registers 3 176 Model 8642A B Operation OPERATING MESSAGES CONTENTS Figure 3 19 Message Related Keys 3 178 Hardware Error Messages 3 193 Information Messages 3 194 Mn MESSAGES iE Prompt Messages 3 196 Q d Mes ros 2 Out of Lock Messages 3 197 ueued Up Tro baa la Table 3 29 Out of Lock Messages Parameters Changed Messages 3 182 DE TM TEENS d Execution Error Messages 3 184 3 177 Operation Model 8642A B MESSAGES 86428 SIGNAL GENERATOR 01 2100 MHz The Message key enables you to view queued up messages Pressing the Shift key twice can be used to clear messages from the display and return the display to showing normal instrument settings Figure 3 19 Message Related Keys 3 178 Model 8642A B Description Procedure Operation OPERATING MESSAGES The Op
294. reements and other customer assistance agreements are available for Hewlett Packard products For any assistance contact your nearest Hewlett Packard Sales and Service Office Addresses are provided at the back of this manual Mode 8642A B Contents CONTENTS SECTION 1 GENERAL INFORMATION Introduction to the Operating and Service Manual 1 1 Volume I Operating 1 1 Volumes H through IV Service 1 1 1 Where to Find Instrument 1 1 Where to Find Safety Considerations 1 2 Hewlett Packard Interface Bus HP IB Enables 1 2 Remote Control of the Instrument 1 2 Selecting the HP IB Address quce PEE 1 2 HP BCapabilties 2222s 1 2 An Explanation of On Site Service Strategy 1 3 Hardware features 3 23 uu s au dues vec ques Gv wa Rea nde a SI 1 3 Built in Test Features c L e uwa ate ua NSF So fs ah AED 1 3 Firmware Features gt e ew wu e p ut a a S eM cs 1 3 How the Operating Fundamentals Can Help You Learn to Operate the Instrument 1 3 Accessories Supplied With the 8642 7 1 4 Options Ava
295. ring terminals power cord or supplied power cord set 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 Contents Indicates hazardous voltages Indicates earth ground terminal The WARNING sign denotes a hazard It calls attention to a procedure practice or the like which if not correctly performed or adhered to could result in personal inju ry Do not proceed beyond a WARNING sign until the indicated conditions are fully understood and met The CAUTION sign denotes a haz ard It calls attention to an operating procedure practice or the like which if not correctly performed or adhered to could result in dam age to or destruction of part or all of the product Do not proceed beyond a CAUTION sign until the indi cated conditions are fully understood and met WARNING Any interruption of the protective ground ing conductor inside or outside the instru ment or disconnecting the protective earth terminal will cause a potential shock hazard that could result in personal injury Ground ing one conductor of a two conductor outlet is not sufficient protection Whenever it is likely that the protection has been impaired the instrument must be made inoperative and be secured against any unin tended operation If this instrument is to be energized via an autotransformer for volta
296. rnal modulation source level is too high or too low to obtain the displayed depth or deviation M FM AM These annunciators can indicate the type or types of modulation selected START When the START annunciator in the left portion of the display appears with the AMPTD annunciator a start amplitude is currently displayed When this annunciator appears without the AMPTD annunciator a sequence is being set INT EXT AC D Combinations of these annunciators display the current status of the modulation source for the displayed modulation type AMPTD AMPTD indicates that the output amplitude is being displayed REL The REL annunciator in the right portion of the display indicates the current output amplitude is displayed in relative units STOP The STOP annunciator can indicate that the stop frequency of the RF frequency sweep is currently being displayed or that the stop amplitude of amplitude sweep is currently being displayed or that sequence is being set When MSSG is displayed you can select the Message key to display a queued up message rev 20MAR 85 3 207 Appendix D Model 8642A B Appendix D Display Annunciators and Abbreviations cont d Many abbreviations are used in the display of the 8642A B Some of these abbreviations are listed below in alphabetic order Abbreviations used 1n messages that have alphanumeric codes are described in the message list that begins on page 3 182 AA AB AM AP OFF DB DM EXT
297. rnal reference Internal hardware had not been able to phase lock to the external reference but now ap pears to be in lock FM phase lock loop cannot track and lock to the time base FM phase lock loop had not been able to track and lock to the time base but now ap pears to be able to track and lock to the time base Output Section ALC loop is out of lock Output Section ALC loop had been out of lock but now appears to be in lock Reference phase lock loop is out of lock Reference phase lock loop had been out of lock but now appears to be in lock Sum loop is out of lock Sum loop had been out of lock but now ap pears to be in lock IF phase lock loop is out of lock IF phase lock loop had been out of lock but now appears to be in lock Heterodyne module SAW loop is out of lock Heterodyne module SAW loop had been out of lock but now appears to be in lock SAW loop is out of lock SAW loop had been out of lock but now ap pears to be in lock Model 8642A B Appendix Appendix A GLOSSARY absolute units In the 8642A B absolute units are units that can be set directly without using the relative amplitude mode These include dBm V mV uV EMF V EMF mV and EMF uV active function When a function is active you do not need to select the function s key before changing its value with either the Knob or Step or Data keys or the Off On key A function is usually indicated as active when the cursor in the displ
298. rocedure before continuing rev 08JUL88 Performance Test 3 4 11 Performance Tests Model 8642A B Calibration Perform the Level Accuracy Performance Test Performance Test 1 at 1000 MHz also use 1300 MHz for HP 8642B and 0 40 80 dBm If the measuring receiver is an HP 8902 store calibration values when instructed by notes 2 7 in Performance Test 1 tables On Off Ratio 1 On the HP 8642 key in AMPTD 10 dBm SHIFT PULSE ON OFF EXT DC This will put the HP 8642 in pulse modulation mode with the modulation waveform in its off state 2 Put the measuring receiver in Tuned RF Level Mode 3 Set the HP 8642 and measuring receiver frequency to the values listed in the table below 4 Verify the readings are lower than the specified maximum RF Frequency 1 00 E 6W 1300 0 1 2 100 00 E 12W 1 On the HP 8902A Measuring Receiver press blue SHIFT RECALL followed by the numeric key indicated by this note number 2 8642B only 4 12 Performance Test 3 rev 08J UL88 Model 8642A B Performance Tests Performance Test 4 RESIDUALS TESTS Specifications Electrical Characteristics Performance Limits Residual AM lt 0 01 AM rms 0 3 to 3 kHz BW Residual FM lt 5 0 Hz rms band 10 0 3 to 3 kHz BW lt 2 0 band 9 lt 1 2 band 8 lt 1 0 band 1 7 lt 3 5 band Residual FM lt 9 0 Hz rms band 10 0 05 to 15 kHz BW lt 5 0 band 9 lt 2 0 band 8 lt 1 2 band 1 7 lt 5 0 band HET
299. roceed with the following example ww mm omm em LOCAL program AP 20 DB APRZ codes REL ZERO Operation Model 8642A B Relative Amplitude cont d Display v FA FA T T 101 REL The AMPTD REL annunciators indicate the amplitude display is relative to a reference amplitude The amplitude is now displayed as 0 0 dB relative to 20 dBf Note that the amplitude reference would be displayed as 100 dBm because the reference can only be displayed in absolute units REF SET Example 4 Configure the front panel to display all output amplitude values as an offset from a 12 dBuV amplitude reference Actual amplitude references in units of dBuV or dB relative cannot be directly set however REL ZERO CAMPTD can be used First select INSTR PRESET to put the instrument in a known state then ENTRY ENTRY LOCAL keys erro T wm 12 DU APRZ codes Display ww I ra r r r r 7 ul The AMPTD REL annunciators indicate the amplitude display is relative to a reference amplitude The displayed amplitude is 0 0 dB the actual amplitude output can be displayed in dBm by selecting REF SET SHET FREQ The dBm key will function as a dB key when the amplitude setting is relative Note that the amplitude reference would be displayed as 95 dBm because the reference can only be displayed in absolute units
300. rough 4 A flashing display indicates that an operating message is present Refer to the tabbed Messages information later in this section for details rev 30SEP88 3 1 Operation Model 8642A B DETAILED OPERATING INSTRUCTIONS The Detailed Operating Instructions are organized into major categories that are decribed on the previous page under the Introduction to Section III Each operating instruction begins on a right facing page for easy accessibility This eans that sometimes you will see a blank page before the beginning of an operating instruction Each of the Detailed Operating Instructions provides specific function related information We have arranged each of these instructions in the following format Description The information given under Description provides an overall description of the function s to be discussed in that particular operating instruction The Signal Generator s front panel functions are divided into three types Key Functions Shift Key Functions and Special Functions Key Functions Key functions are labeled directly on the key that accesses the function You can access a key function by pressing the key directly In these instructions we show the key function s label in capital letters surrounded by what resembles a key shape for example FREQ or CAMPTD Shift Key Functions Shift key functions are labeled in blue above the key that accesses the function for example REF SET or REL ZERO Y
301. s 125 9E 03 12 30E 03 3 981E 03 1 259E 03 125 9E 06 12 59E 06 1 259E 06 125 9E 09 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 125 9E 15 12 59E 15 1 259E 15 251 2 18 125 9 03 12 30 03 3 981 03 1 259E 03 125 9E 06 12 59E 06 1 259E 06 125 9E 09 12 59E 09 1 259E 09 125 9E 12 12 59E 12 1 259E 12 125 9E 15 12 59E 15 1 259E 15 251 2E 18 rev 08JUL88 Model 8642A B rev 08JUL88 HP 8642 AMPTD dBm 1 HP 8642B only 2 HP 8642A only 8642 FREQ MHz Measuring Receiver Frequency Measuring Receiver Mode RF POWER RF POWER RF POWER TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF RF POWER RF POWER RF POWER RF POWER TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF Performance Test Record 79 43E 03 7 762E 03 2 510E 03 794 3E 06 79 43E 06 7 943E 06 794 3E 09 79 43E 09 7 943E 09 794 3E 12 79 43E 12 7 943E 12 794 3E 15 79 43E 15 7 943E 15 794 3E 18 158 5E 18 63 09E 03 50 12E 03 7 762E 03 2 510E 03 794 3E 06 79 43E 06 7 943E 06 794 3E 09 79 43E 09 7 943E 09 794 3E 12 79 43E 12 7 943E 12 794 3E 15 79 43E 15 7 943E 15 794 3E 18 158 5E 18 125 9E 03 12 30E 03 3 981E 03 1 259E 03 125 9E 06 12 59E 06 1 259E
302. s Frequency Sweep Set the instrument to a known state by selecting INSTR PRESET Set a Phase Continuous Frequency Sweep from 250 2 to 250 3 MHz at the minimum possible sweep time This sweep will occur in divide band 7 with divide number 4 Minimum sweep time is equal to the maximum of 5 ms or Minimum Sweep Time 250200000 250300000 x 4 X 0 002 ms 800 ms Since 800 ms is greater than 5 ms 800 ms is the minimum sweep time Also since 800 ms is an integer number of ms this value can be set directly 3 62 Model 8642A B Operation RF Frequency Sweep cont d Example for Phase Continuous Frequency Sweep cont d SPCL START AUTO AMPTO LOCAL keys C2 JUs Co C JU program codes SP123 FASA ST 800 MS FA 250 2 MZ FB 250 3 MZ These codes are not independent and might need to follow a specific sequence for entry Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section III Display w FA FA FA ITI 7 FA Z3 FA PA FA PA FA ITI 7 eoudguuB dhz The display usually shows the start frequency and the stop frequency settings If another active function is selected the display could indicate frequency sweep with the SWPNG annunciator or by displaying FRQ SWEEPING in the left portion of the display above the FREQ annunciator The SPCL annunciator is also displayed To see that Phase Continuous Frequency S
303. s addressed to talk it will output a number representing the displayed annunciators in a binary weighted sum This string length will also always be less than 25 characters Each item in the sequence above will be output again in the same sequence when the Signal Generator is further addressed to talk Following is a programming example in BASIC for outputting display information Output the current display of the Signal Generator address 19 including the cursor position and annunciators Assuming a function was executed to enable you to get the display you want 10 DIM A 74 20 ENTER 719 A 30 ENTER 719 C 40 ENTER 719 N Define string big enough to handle maximum display Display String Cursor Value Annunciator Value em cm The Signal Generator is initialized to output the alphanumeric display string first whenever you execute an instrument function for example set AM or frequency When you are using Output Display to output messages the actual front panel display will be output not the message code number that would be output if you used OC OE or OH The binary weight of the cursor positions are 2 2 for the left most cursor 2 4 for the next cursor to the right 23 8 for the next cursor to the right 2 for the nth cursor position from the left 2 33 554 432 for the right most cursor The binary weight of the annunciators are provided in the following Table 3 5 3 21 Operation
304. s always an integer in 0 1 dB units since end points are integers in 0 1 dB units The start and stop amplitude setting values must be in dBm in order to perform these calculations Refer to Amplitude Units Conversion on page 3 205 for information about changing amplitude values to dBm and back to other units 1 Calculate the number of steps automatically selected The number of steps is the minimum of Start Amplitude in dBm Stop Amplitude in dBm 0 1 dB or INTEGER OF Sweep m in ms Model 8642A B Operation Amplitude Sweep cont d 2 Calculate the sweep step size automatically selected The result can be a non integer but actual amplitude points are truncated to 0 1 dB the total number of points is equal to the total number of steps 1 The sweep step size is the maximum of 0 1 dB Start Amplitude in dBm Stop Amplitude in dBm Sweep Time in ms E 1 3 ms INTEGER OF 3 Calculate a sweep time that could be selected for a desired number of steps 3a First you must ensure that the desired number of steps is between the maximum and minimum number of steps possible The maximum number of amplitude steps is equal to Start Amplitude in dBm Stop Amplitude in dBm 0 1 dB The minimum number of amplitude steps equals the minimum of or Start Amplitude in dBm Stop Amplitude in dBm 0 1 dB 3b If the desired number of steps is equal
305. s follows VIDEO BW Laya sa ces 1Hz SWEEP TIME 2er ec ie Ia E PRU Taba Mis 5 0 sec ATTENUATION 10 dB RESOLUTION aucti onsen stemmed 10 Hz CENTER soy ers aetna eGeocs SA au 20 kHz SPAN Sa z sasawa Ra RR HEMDEN aa ROMERO OM 0 Hz REFERENCE LEVEL 90 dBm NOTE It may be necessary to fine tune the spectrum analyzer center frequency adjustment The spectrum analyzer band width will be centered when the maximum signal level is obtained while tuning the center frequency adjustment 4 Record the level of the 20 kHz peak signal for later use dBm CAUTION Using the oscilloscope verify that no large AC signal is present If AC is present the mixer input signals are not at the same frequency and spectrum analyzer damage may result 4 36 Performance Test 11 rev 08JUL88 Model 8642A B Performance Tests 5 Set the HP 8642 to 10 0 MHz then 0 dBm amplitude by incrementing the amplitude in 10 dB steps 6 On the HP 8642 enter SPCL 250 to enable phase adjust with the knob View the signal in the dc coupled mode on the oscilloscope Use the HP 8642 knob to adjust the dc level on the oscilloscope as close to zero as possible This sets the two input signals to the mixer in phase quadrature 90 degrees out of phase 7 Set Spectrum Analyzer to 0 dB attenuation and reference level 50 dBm 8 View the trace and note the average n
306. s in use These spurs will be eliminated when no internal modulation source is modulating the carrier and the modulation oscillator out put MOD OUT is off HP IB Sequence Dependency M settings are sometimes coupled with other functions Therefore HP IB codes may need to be entered in a particular sequence when accessing combinations of these func tions Refer to the discussion about Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section IIT 7 Low Distortion On In the mode the low distortion function is limited by the actual frequency deviation Therefore to use Special Function 7 for you need to calculate frequency deviation as the phase deviation in radians times the modulation frequency in Hz Frequency deviation must be less than 7 of the maxi mum allowable frequency deviation for the RF frequency chosen 207 Low Distortion FM M Off This special function switches out the shaper cir cuitry inserted with Special Function 7 rev 20MAR 85 Model 8642 A B Operation Modulation cont d 113 Modulation Frequency Correction Off This special function disables the single band calibration of the modulation frequency oscillator that normaily occurs whenever the modulation oscillator frequency is set or the internal modulation oscillator is put into use When this calibration is disabled the typical modulation frequency switching time is decreased by approximately 200 ms
307. s not allow simultaneous AM and pulse modulation or FM and M FM is allowed in the following combinations Any one of these types Internal FM External ac or dc coupled FM Internal external ac or dc coupled FM External low rate FM Special Function or Internal external low rate FM Special Function 112 With any one of the following Internal AM External ac or dc coupled AM Internal external ac or dc coupled AM Internal pulse modulation or External dc coupled pulse modulation eee NOTE All internal modulation sources use the internal modulation oscillator therefore all internal modulation as well as MOD OUTPUT have the same modulation frequency 3 111 Operation Model 8642A B Modulation FM cont d How to Obtain Low Residual FM At high FM deviation settings the residual FM performance of the Signal Generator can be limited by ground loops set up between the external FM source and the Signal Generator For minimum residual FM a floating external FM source should be used How to Obtain Maximum FM Stereo Separation Maximum stereo separation at least 50 dB is achieved in the heterodyne band with dc coupled FM Low Distortion FM Special Function 7 may be selected to further reduce total harmonic distortion HP IB Sequence Dependency FM settings are sometimes coupled with other functions Therefore HP IB codes may need to be entered in a particular sequence when accessing com
308. s only necessary to adjust that module Therefore the adjustments have been integrated into the Troubleshooting Information in Section 8 For example After two years of operation you find that AM distortion performance is at the extreme limits given in Table 1 1 After using Module Substitution see On Site Service Manual to isolate the problem to A13 you turn to the A13 tab in Section 8 You perform the AM Distortion Adjustment followed by the A13 Auto Adjust Routine The AM distortion performance is now returned to nominal 5 2 AUTO ADJUST ROUTINES Description In the service documentation for the HP 8642 there will be references to Self Cal Self Calibration and Auto Adjust These three terms refer to the same firmware routines built into the HP 8642 that are used to regenerate module correction data sometimes refered to as Cal Data The Cal Data is stored in EEPROM on the A3 board and is used to control the modules during instrument operation A back up copy of the Cal Data is stored in EEPROM on the A20 board which is located under MP 65 on the rear panel The Auto Adjust routines control external measurement equipment via HP IB for the purpose of regenerating A2 All 12 AI3 and 14 module correction data after a component level repair of the module External measurement equipment required includes a voltmeter printer and HP 8902A In some cases an HP 8901B may be substituted for the HP 8902A The printer must have HP
309. se Continuous Frequency Sweep During Phase Continuous Frequency Sweep Special Function 123 dc coupled FM is not possible when either DC FM Update Mode Special Function 117 or DC FM Correction Special Function 216 is selected Zero Span for Stepped Frequency Sweep To calculate the number of X axis steps automatically selected for zero span using Stepped Frequency Sweep refer to calculation 1 on page 3 53 To calculate a sweep time that could be selected for a desired number of X axis steps refer to calculation 3 on page 3 54 The maximum number of X axis steps is 1023 or 1024 points Zero Span for Phase Continuous Frequency Sweep Special Function 123 To calculate the number of X axis steps automatically selected for zero span using Phase Continuous Frequency Sweep refer to calculation 5 on page 3 62 X AXIS A OV to 10V stepped output is available at the X AXIS output connector on the rear panel The frequency points at the output coincide with the points in the sweep time calculations for Stepped Frequency Sweep For Phase Continuous Frequency Sweep frequency changes in a phase continous manner while the X axis output changes in steps Z AXIS A blanking pulse is available at the Z AXIS output The blanking pulse is TTL positive true for CRT blanking during retrace There is a time that occurs between the end of the sweep and the beginning of the next sweep while the Z AXIS output is blanked and the frequency and X AXIS out
310. se HELP CSHIFT and one of the methods described below How to List the Descriptions of Special Functions on the Signal Generator s Display HELP CSHFT followed by one of the following methods Rotating the Knob Pressing one of the Step keys or Keying in the numeric code of the special function you want described Special function codes can be keyed in one right after the other with no need for re selecting the Help function The SPCL annunciator will not be displayed under the special function description because special functions are being described not selected The Help function can be turned off either by selecting HELP OFF SHIFT J HP IB code HO or by selecting other signal Generato functions Example Display the description of Special Function 112 program codes 3 167 Operation Model 8642A B Special Functions cont d Display LOWRATE FM The Signal Generator displays the code and description of Special Function 112 This special function is not turned on with the Help function note the absence of the SPCL annunciator Now you can turn the Knob or use the Step keys to view the codes and descriptions of other special descriptions SPCL How to Select Special Functions SPCL SHIET C and the desired special function numeric code The SPCL annunciator will be displayed below the special function description after the special function is selected Example
311. se a sweep time setting greater than or equal to the result of the above calculation but less than the result of the following calculation Start Frequency He Stop Frequency in Hz z Min pell Time Gh ms Step Size in Hz N Operation Model 8642A B RF Frequency Sweep cont d Example for Calculation 4 Stepped Frequency Sweep In an 8642B set a stepped frequency sweep from 100 to 500 MHz with a sweep step size of 8 MHz with Special Function 219 Re Enable Settling First select Instrument Preset Calculate the required sweep time setting for an 8 MHz step size using calculation 4 Ensure that an integer results when the frequency span of 400 MHz is divided by the step size of 8 MHz 400 MHz MH 00 Maximum step size is equal to the maximum of 1 Hz or 100 000 000 Hz 500 000 000 Hz 400 000 000 Hz or 400 MHz INTEGER oF 222 15 Since 400 MHz is greater than 1 Hz the maximum step size is 400 MHz Minimum step size 1s equal to the maximum of 1 Hz or 100 000 000 Hz 500 000 000 Hz 1023 391 006 Hz or 0 391006 MHz Since 0 391006 MHz is greater than 1 Hz the minimum step size is 0 391006 MHz Therefore it should be possible to select an 8 MHz step size since that value is between the minimum value 0 391006 Hz and maximum value 400 MHz 3 58 Model 8642A B Operation RF Frequency Sweep cont d Example for Calculation 4 cont d To obtain a
312. should be adjusted to a 1 Vpk 0 707 Vrms sinewave input to the Signal Generator to get the displayed FM deviation With an external 1 Vpk signal applied the Signal Generator modulates its RF output to achieve the deviation setting For example if a 1 Vpk external modulation source is provided with the Signal Generator s FM deviation set to 50 0 kHz per volt the output has 50 0 kHz FM deviation If the source voltage is reduced to 0 5 Vpk and no other settings are changed the output has 25 0 kHz FM deviation If the HI and LO annunciators are not displayed then the externaly modulation signal is between 0 95 Vpk and 1 05 Vpk The HI LO annunciators only apply to sinewave inputs The HI LO detectors do not monitor dc voltage Input levels External Coupling Any one of the following functions can be used to couple the external FM M INPUT to the FM circuitry AC Coupled Source e EXT AC This function selects the external ac coupled FM source displaying the EXT and AC annunciators EXT AC EXT AC J This function selects the external ac coupled FM source and internal FM source summed together displaying the INT EXT and AC annunciators e EXTERNAL LOW RATE FM Special Function 5 This function selects the external ac coupled FM source for 0 4 Hz to 200 kHz rates displaying the EXT annunciator Refer to page 3 112 for more information about this special function INTERNAL EXTERNAL LOW RAT
313. state Partial Preset s 3 a quick way to set the Signal Generator to another initialized state without affecting some instrument settings for example Partial Preset does not turn off the EMF or Amplitude Relative mode Holding the Shift key down during power up until instrument settings are displayed bypasses the power up checks The Knob usually modifies a specific digit in the display The keys can select which digit will be modified The keys can also select Knob Hold or Knob Increment The Step keys enable you to step a function by the value that was set using the key The Off On key toggles an active function off or on with a single keystroke The Entry Off function disables the active function as well as all Knob related functions Figure 3 16 Functions Related to Modifying Settings Model 8642A B Description Procedures POWER Operation INSTRUMENT PRESET PARTIAL PRESET Signal Generator settings can be reset by switching the Power from standby to on selecting Instrument Preset or by selecting Partial Preset The instrument is turned on by switching POWER from STBY to ON When it is turned on the Signal Generator goes through a sequence of internal checks If the instrument encounters no problems it sets itself to the initialized state that is set up with Instrument Preset If any failures occur during the power up self check hardware messages are queued up to be selected with the
314. strument displays a message you want clarified 3 169 Operation Model 8642 Special Functions cont d Table 3 28 Summary of Special Functions Function to Code K gt Special Function Description ser G 8 208 RF Frequency Prefer Heterodyne Band Decrement Frequency by 0 1 Hz increment Frequency by 0 1 Hz Phase Adjust by Knob or Step Keys Phase Decrement 1 Phase Increment 1 Phase Decrement 5 Phase Increment 5 Amplitude ALC Off Attenuator Range Hold Disable Settling Externa Low Rate FM Internal External Low Rate FM FM Pre Emphasis Low Distortion Negative FM Polarity DC FM Oorrection Off DC FM Update Mode AC Coupled DC FM Prefer Heterodyne Band Disable Settling Low Distortion Negative Polarity Prefer Heterodyne Band Disable Settling Modulation Modulation Frequency Correction Off 113 213 Oscillator Calibrate Modulation Frequency Bands Again 248 Sweep Up and Down 121 221 Linear Amplitude Sweep 122 222 Phase Continuous Frequency Sweep 123 223 Disable Settling 119 219 Miscellaneous Special Functions 4 9 Off All Special Functions lt 200 Off Special Function Verification Off Display Firmware Information Disable Display Turn Off LCD Lighting Clear Recall Registers Service Mode see Service Manual pes d s 3 170 Model 8642A B Special Functions cont d 100 111 112 113 114 115 116 117 118 119 121 122 123 134 135
315. t 1 17 re 15NO V90 Contents Model 8642A B SECTION 2 INSTALLATION Introductions u p VT wena ELDER RE SI neveu e wie e cart REED d ie 2 1 ImtalInspection Bale k yaa xeu eue deed Boe BIE Ae we 2 1 Preparation Bor Use pcd E WR UE ue Aeg atu Sae s Nada Ge Snap osi 2 1 Power Requirements 2 1 Power Cables no VIN v pu sme eR REVO CUP Qe ONE Dd ce EX us 2 8 HP IB Address Selection cele le 2 5 Interconnections u l I Be Be Ux NUR Pw rudis eR E NIE MR popu 2 5 Mating Connectors sosse e aye u Bo Sole assem E eee 2 5 Operating Environment s sT oee a Eea ee es 2 5 Rack Mounting ou u uS uu ar UAM we arie C voe erg 2 Storage andShipment ee 2 6 Environment 3 9 oS us RU Are eS ee s dot wd EP 2 6 Packaging s kus Sa SENI dox aN tatas noto gos err e uL us 2 6 Figure 2 2 HP IB Connections 2 7 SECTION 3 OPERATION Introduction to Section 3 3 1 Detailed Operating Instructions e a ee 3 2 Figure 3 1 Basic Functions 3 3 Figure 3 2 Rear PanelFeatures _ _ _ ee ee es 3 4 HP IB Table of Contents
316. t as HP part number 5061 0083 Rack Slide Kit information is listed on the following page under paragraph 1 10 Equipment That Can Be Ordered for the Signal Generator If you are planning to take advantage of the On Site Service Strategy for the HP 8642A B we suggest you use the Rack Slide Kit when rack mounting the instrument rev 30SEP88 Model 8642A B General Information Documentation Options Option 910 Extra Manual This option provides an additional Operating and Service Manual Volumes I through IV Order the additional manual as HP part number 08642 90012 Option 710 On Site Service Manual The On Site Service Manual is a service tool directed at speedy troubleshooting and repair of the HP 8642A B to the module level The manual provides a systematic approach to troubleshooting which directs the technician through instrument checks module group checks and then specific module checks The On Site Service Manual is designed for use with the On Site Service Kits Refer to paragraph 1 10 below Order the On Site Service Manual as HP part number 08642 90020 It is not necessary to order option 710 if an On Site Service Kit is ordered 1 10 EQUIPMENT THAT CAN BE ORDERED FOR THE SIGNAL GENERATOR On Site Service Kits Each of these kits contains an On Site Service Manual in addition to all HP 8642A B modules and interconnecting cables required for on site module level repair Each kit also includes a set of tools not normally
317. t change the next sequence register number However recalling a register might change the next sequence register number in the sequence if the recalled register is in the selected sequence Recalling an Undefined Register Recalling a register that is not defined causes messages E93 RECALL NOT DEFINED E93 and H10 RECALL ERROR FOUND H10 These messages could be caused due to previously executing Special Function 251 Clear Recall Registers RAM being lost for example if the battery lost its charge or recalling a register before anything is saved in that register HP IB Executing Error message E93 occurs immediately afer recalling an empty register So by noting the occurence of E93 by enabling execution errors to pull SRQ refer to Service Request on page 3 27 in the HP 1B portion of this Section III you could find out which register you recalled was not defined Related Special Functions 251 Clear Recall Registers This special function clears all recall registers Operation Model 8642A B Save Recall cont d Related Operating Instructions Refer to Sequence page 3 161 for information on sequencing through a sequential group of recall registers Refer to Special Functions page 3 165 for information about the way these are accessed Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified 3 160 Model 8642A B Description Procedure SET SEQ Operation SEQU
318. t using Special Function 3 for servicing the instrument Select any function to exit this mode 3 194 rev 20MAR85 Model 8642A B Operation Operating Messages cont d SYS CONTROL DISABLED 131 HP IB system control capabilities were just disabled The HP IB address was just set which disables the Signal Generator s system control capabilities accessed with Special Function 3 Refer to the Service Manual or On Site Manual for information about using Special Function 3 for servicing the instrument ADRS LISTEN ONLY 132 The instrument is configured as a listen only device over HP IB Refer to HP IB Address page 3 8 in the HP IB portion of this Section III LISTEN ONLY DISABLED 133 The instrument is no longer configured as a listen only device The instrument s HP IB address setting was changed from 31 to a value between 00 and 30 Refer to HP IB Address page 3 8 in the HP IB portion of this Section III WAIT FOR FM LOOP LOCK 140 Wait for the Signal Generators internal FM circuitry to complete its setting This message cannot be read via HP IB using Output Display because it automatically clears from the display after execution completes This message is displayed when switching from a dc coupled FM source to a non dc coupled FM source No additional external settling time allowance is necessary to settle within 100 Hz of the selected frequency RF FREQ DISPLAY 0 9 HZ 149 RF FREQ DISPLAY 0 8 HZ 148 RF FREQ DISPLAY 0 7 HZ 147 RF F
319. te gt 50 kHz HP 8116A ME Min Pulse Width 6 psec HP 8662A for Rise Time 100 nsec Optional Residual FM Test Residual SSB phase noise in 1 Hz BW 320 MHz lt f lt 640 MHz with an offset from the carrier of 100 dBc at 10 Hz 121 dBc at 1 kHz and dBc at 10 kHz Short Type N Short Type N N HP HP 115124 Feedthrough Termination ohms 1 HP e BNC see Table 1 4 1 Performance Testing A Adjustments T Troubleshooting Signal Generator optional 10 uH 10 uH t j T p cw S lt i i Figure 1 1 1 MHz Low Pass Filter Table 1 4 Alternative Test Equipment Recommended Model Suggested Alternative Advantage of Alternative Digital Voltmeter DVM HP 3456A HP 3455A Satisfies the requirements for testing the Signal Generators Signal Generator HP 8642B HP 8340A Satisfies the requirements for testing HP 8341A the Signal Generator except HP 8663A 1 Third Order Intermodulation Test re HP 8662A quires 18 dBm at 1050 MHz 2 Optional Phase Noise Test requires phase noise less than or equal to the unit under test The 86624 satisfies the RF frequency range for 86424 testing Oscilloscope HP 1980B HP 19860A HP 1740A Satisfies the requirement for testing the Signal Generator Feedthrough Termina HP 11095A HP 0757 1100 Satisfies the requirement for test
320. ted 6 FM Pre emphasis On Special Function 6 can be selected to pre emphasize internal or external FM modulating signals with a 750 us time constant Pre emphasis boosts high frequencies in the modulating signal prior to modulating the carrier Refer to Modulation FM page 3 113 7 Low Distortion FM 4M On This special function switches shaper circuitry into the FM M loop reducing total harmonic distortion Refer to either Modulation FM page 3 115 or Modulation page 3 124 8 Prefer Heterodyne Band This special function causes the Signal Generator to operate in the heterodyne band at RF frequencies below 132 187501 MHz regardless of FM or deviation or Phase Continuous Frequency Sweep Span Refer to RF Frequency page 3 39 9 Attenuator Range Hold On When Attenuator Range Hold is selected the Signal Generators output attenuators are fixed and the output ALC loop controls signal amplitude This produces a 30 dB range with monotonic step to step amplitude increments Refer to Amplitude page 3 74 100 AllSpecial Function Codes Less than 200 Off This special function turns off special functions 4 through 9 111 through 119 121 through 123 134 and 135 Sometimes all these special functions will not be turned off if the instrument state is dependent on a special function A message will be displayed to notify you if a special function remained on after you selected Special Function 100 Special functions can also be t
321. ted in the table Measure the reflected power at all settings and record each reading under Intermediate Readings Reflected 2 3 4 Set the Signal Generator and measuring receiver frequency to values listed in the table below 5 6 Signal Intermediate Results Generator Readings Return Loss Frequency MHz 4 000 4 000 1000 000 1000 000 1300 000 1300 000 Low Level SWR Return Loss Calculation 1 In each row in the preceding table compute the Actual return loss using the following formula Ref Reflected Actual 2 Verify that Actual is greater than the specified Min NOTE If you wish to compute the actual SWR from the return loss at each frequency you may use the following formula _ l 107 ReturnLoss 20 SWR FL 1 10 ReturnLoss 20 4 30 Performance Test 8 rev 08JUL88 Model 8642A B Performance Tests Performance Test 9 SPURIOUS TEST Specification Electrical Characteristics Performance Limits 100 dBc 94 dBc band HET 9 band 10 Non harmonic spurious Description The RF output of the HP 8642 is viewed on a spectrum analyzer The HP 8642 s frequency is set to values where spurious performance problems are most likely to be observed EXTERNAL REFERENCE MR HI cee en SK HP 8642A B SYNTHESIZED SIGNAL GENERATOR Figure 4 9 Harmonics and Spurious Test Setup Equipment Spectrum Analy Zens us ua au ok rates 4 be eh aw Ma
322. ter codes into already full message This message sets the Execution Error bit in the 8642A B Status Byte MESSAGE 2 IS FULL N93 21093 This message might occur after attempting to enter codes into an already full message This message sets the Execution Error bit in the 8642A B Status Byte MESSAGE 1 UNDEFINED N94 21094 This message might occur when manipulating message 1 The message means that message 1 has not been initialized or RAM memory was lost To initialize the message select 6 5 CS This message sets the Hardware Error bit in the 8642A B Status Byte MESSAGE 2 UNDEFINED 95 21095 This message might occur when manipulating message 2 The message means that message 2 has not been initialized RAM memory was lost To initialize the message select 6 C6 5 This message sets the Hardware Error bit in the 8642A B Status Byte COMMENT If the user defined message begins with a set of characters resembling the alphanumeric codes used in message displays the firmware will automatically place those characters at the far right of the display If this right justification is not desired put a space character at the beginning of the message 3 204 rev 20MAR85 Model 8642 Appendix C Appendix C AMPLITUDE UNITS CONVERSION You can use this information to convert the output amplitude to practically any desired units This information might be useful for example to convert between dBm and volts or EMF mV and dBm
323. terodyne Band and FM To resolve this error either 1 turn off frequency sweep HP IB FAOF FBOF and then possibly select Stepped Frequency Sweep Special Function 223 or 3 188 Model 8642A B Operation Operating Messages cont d 2 select a valid sweep time setting refer to RF Frequency Sweep page 3 60 or 3 possibly turn off FM or select Special Function 208 Prefer Divide Bands or 4 refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III AP SWP PREVENTS FR SWP E52 4052 Amplitude sweep and frequency sweep cannot be done simultaneously Turn off amplitude sweep HP IB AAOF ABOF before attempting frequency sweep FM PREVENTS AUTO SWP E53 4053 FM during Stepped Frequency Sweep is only possible in manual and single sweep modes Possibly refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section AUTO SWP PREVENTS FM E54 4054 FM during Stepped Frequency Sweep is only possible 1n manual and single sweep modes Possibly refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III FR SWP FM LIMIT E55 4055 FM is coupled with frequency sweep and one of those settings is limiting the setting of the other This message could also have been caused by executing Special Function 0 or 100 when one special function was coupled to other instrument settings Either set FM deviat
324. th an External Source 3 108 HP IB Codes 3 110 Comments ura u Susu pawa Susa aypaq ss 3 110 Table 3 20 Maximum FM Deviation Settings with Only an External Source 3 112 Related Special Functions 3 112 5 External Low Rate FM On 3 112 112 Internal External Low Rate FM On 3 112 6 FM Pre emphasis On 3 113 Figure 3 14 FM Deviation Limits with without FM Pre Emphasis 3 114 Table 3 21 Factor for Y Axis FM Deviation Quotient 6 oc deer sa 3 115 7 Low Distortion FM M On 3 115 113 Modulation Frequency Correction Off 3 115 115 Negative FM Polarity 3 115 116 DC FM Correction Off 3 116 117 DC FM Update Mode On 3 116 118 AC Coupled DC FM On 3 116 119 Disable Settling 3 116 248 Calibrate the Modulation Frequency Bands Again 3 116 Operation MODULATION 3 119 ana RPM ECC Ni 3 119 Table 3 22 Operating Characteristics 3 119 Figure 3 15 M Deviation Limitations for each RF Frequency Band 3 119 INT viuo LU y Saa utasa breed sti e E e 3 120 How to Set M with the Internal Source Using the Modulation Oscillator 3 120 EXT AC EXT DO eor Iber el 3 121 How to Set with an External Source
325. the 1 Hz digit the display resembles a Knob Hold condition because the cursor would be over the of the MZ terminator during Knob Hold also Knob Hold is discussed on Page 3 143 RF Frequency Settings Interact with Other Instrument Settings Some settings are limited by the interaction of coupled functions for example FM deviation and RF frequency Refer to the appropriate Detailed Operating Instruction for setting limitations and be aware that any restrictions are due to the absolute output frequency not the relative frequency setting Relative RF Frequency Sweep It is not possible to set an RF frequency sweep in relative units Related Operating Instructions Refer to RF Frequency page 3 42 for additional comments that apply to relative frequency Also refer to page 3 42 for information on changing RF frequency by 0 1 Hz increments Special Functions 240 241 and for information on incrementing or decrementing RF output phase in 1 or 5 degree increments Special Functions 242 through 245 and 250 Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for Bonon about the way these are accessed Mode 8642A B Description RF FREQUENCY SWEEP Operation Two types of frequency sweep are available Stepped Frequency Sweep s
326. the amplitude setting to read as an offset from the Signal Generator s last selected reference Once an amplitude reference is selected all subsequent amplitude settings are entered and displayed as relative amplitudes in terms of dB above or below the amplitude reference This condition exists until the Relative Amplitude mode is turned off The actual output amplitude is equal to the sum of the amplitude reference and the displayed amplitude Note Put the instrument in its initialized state by selecting INSTR PRESET How to Set the Current Output Amplitude Setting To Be the Amplitude Reference Setting the current output amplitude as the amplitude reference causes the amplitude setting display to become 0 0 dB relative REL ZERO SHET AMPTD Example Set the amplitude to any arbitrary level using the Knob Step keys or Data keys For example you might be setting the level to a reference value that depends on a power level being measured elsewhere on a power meter Then zero the Signal Generator s amplitude display REL ZERO AMPTD program codes Operation Model 8642A B Relative Amplitude cont d REF SET Display v I FA TA TATATA TATATA ITI 7 Ti T t CC ed Ki cd ed ed nit d iB The AMPTD REL annunciators indicate that the amplitude display is a relative output All subsequent amplitude settings will be entered and displayed in units of dB relative to the absolute amplitude when the Relative
327. the following table and record the reading for each frequency HP 8642 FREQ Measuring Receiver Results Frequency dBm 6 In the readings taken above indentify the maximum P nax and minimum P power levels 7 Compute the worst case flatness error using the formula below The value must be less than 0 75 dB Pmin dB 4 4 Performance Test 1 rev 08JUL88 Model 8642A B Performance Tests HET Band Level Accuracy 1 On the HP 8642 key in SPCL 8 to enable the HET Band 2 Change the measuring receiver display to linear 3 Set the HP 8642 and measuring receiver to 0 1 MHz 4 Set the HP 8642 to the amplitude levels given in the table below and verify that the readings are within the given limits HP 8642 AMPTD 50 12bE 03 79 43E 03 7 762E 03 12 30E 03 2 510E 03 3 981E 03 794 3E 06 1 259E 03 79 43E 06 125 9E 06 7 943E 06 12 59E 06 Level Accuracy 1 On the HP 8642 key in SPCL 0 to disable the HET band 2 Set the HP 8642 and the measuring receiver to the values given in the tables on the following pages 3 At all 0 dBm amplitude settings change measuring receiver measurement mode to Tuned RF and on the HP 8642 key in INCR SET 10 dBm This will enable the step function to be used see Operating Fundamentals Also if measuring receiver is an HP 8902A return to 0 dBm at the end of each band and store instrument configuration as instructed in notes 2 through 7 4 V
328. time until the approximate desired number of steps or step size is obtained To skip these sweep time details turn to page 3 92 Operation Model 8642A B Amplitude Sweep cont d How to Set Sweep Time Using Sweep Time to Set Amplitude Step Size and Number of Steps The operating characteristics for amplitude sweep time are as follows Minimum Sweep Time 20 ms Maximum Sweep Time 999s Sweep Time Resolution 1 ms Minimum Amplitude Sweep Step Size 0 1 dB Minimum Amplitude Dwell Time per Step 3 ms Amplitude Sweep Calculations Since the sweep step size is not directly selectable the following calculations provide ways to determine 1 the number of stens automatically selected page 3 86 2 the amplitude step size automatically selected page 3 87 3 the required sweep time that will select a desired number of amplitude steps page 3 87 and 4 the required sweep time that will select a desired step size page 3 89 However these calculations do not directly apply to situations when the start end point is equal to the stop end point zero span Refer to Zero Span for Amplitude Sweep on page 3 92 for information about X axis steps in zero span These calculations apply only to logarithmic amplitude sweep Calculations for Linear Amplitude Sweep Special Function 122 are not discussed because calibration data used during linear sweeps is different for each instrument Also amplitude points are truncated to 0 1 dB Span i
329. ting the instrument to an initialized state that maintains preset references including the selected amplitude units Refer to Operating Messages page 3 177 if the instrument displays a message you want clarified Refer to Special Functions page 3 165 for information about the way these are accessed Model 8642A B Amplitude cont d Table 3 15 Attenuator Range Hold Amplitude and AM Ranges Output Amplitude dBm When Attenuator Hold is Selected to to to to to to to to to to to to to to to to to 5 0 0 0 5 0 10 0 15 0 20 0 25 0 30 0 35 0 40 0 45 0 50 0 55 0 60 0 65 0 70 0 75 0 80 0 85 0 90 0 95 0 to 100 0 to 105 0 to 110 0 to 115 0 to 120 0 to 125 0 to 130 0 to 135 0 to 140 0 Available Range of Amplitude dBm Amplitude Range at Which Amplitude is Specified dBm 15 to 10 to 5 to 0 to 5 to 10 to 15 to 20 to 25 to 30 to 35 to 40 to 45 to 50 to 55 to 60 to 65 to 70 to 75 to 80 to 85 to 55 60 65 70 75 80 85 90 95 90 to 100 95 to 105 100 to 110 105 to 115 110 to 120 115 to 125 120 to 130 125 to 135 130 to 140 Amplitude Range at Which AM is Specified dBm 10 to 5 to 0 to 5 to 10 to 15 to 20 to
330. tion code HP IB CODES SUMMARY Table 3 8 Signal Generator Function to HP IB Code Parameter Code Model 8642A B ale Units Cont d radian second millisecond Sweep Sweep Time Auto Sweep Manual Sweep Single Sweep Relative Reterence Set Relative Zero Relative Off Other Instrument Preset Partial Preset Special Function Message Output Hardware Error Output Execution Error Output Parameters Changed Output Active Function Write Service Request Mask Output HI LO Annunciator Status Clear Status Byte Step Up Step Down Increment Set Knob cursor left Knob cursor right Knob Hold Knob Increment Help Help Off RF Off On Off On Entry Off Sequence Set Sequence Save Recall 3 119 3 52 3 85 3 52 3 85 3 52 3 85 3 51 3 84 3 51 3 84 3 51 3 84 3 46 3 78 3 45 3 77 3 47 3 81 3 138 3 139 3 167 3 179 3 17 3 193 3 16 3 184 3 16 3 182 3 18 3 27 3 20 3 29 3 149 3 149 3 149 3 141 3 141 3 143 3 142 3 167 3 167 3 72 3 153 3 161 3 161 3 157 3 159 2Function should be preceded by an active function code For example internal modulation source for AM is coded AMNT 3These codes will sometimes not need to be preceded by an active function code for example when using UP or DN with SV RC HP or SM Model 8642A B Table 3 9 Signal Generator HP IB Code to Function me Pee Start Amplitude Sweep Stop A
331. tion of the On Site Service Strategy for the HP 8642A B Section 2 Installation Installation covers initial inspection preparation for use and storage and shipment Section 3 Operation Operation provides HP IB operating information including HP IB address selection and detailed operating information for either the beginning or experienced user A glossary and index are provided at the end of Section 3 Section 4 Performance Tests Performance Tests enable you to check the performance of the instrument against the specifications listed in Table 1 1 Section 5 Adjustments The adjustment procedures that are normally found in this section are now located in Section 8 with the appropriate troubleshooting procedures and schematics Volumes 2 through 5 Service Manual Section 6 Replaceable Parts Replaceable Parts lists all replaceable parts and assemblies Section 7 instrument Changes Instrument changes provide backdating information and retrofitting and modification information Section 8 Service Service provides the information required to adjust and repair the instrument 1 2 WHERE TO FIND INSTRUMENT SPECIFICATIONS Instrument specifications are listed in Table 1 1 These specifications are the performance standards or limits against which the instrument can be tested Supplemental characteristics are listed in Table 1 2 Supplemental characteristics are not guaranteed specifications but are typical characteristics included
332. tion spectrum analyzer The 10 MHz reference output from the HP 8642 s rear panel is used as the LO input for the mixer The HP 8642 s output is set to 10 MHz and is used as the RF input to the mixer The output of the mixer is viewed on a spectrum analyzer at 20 kHz OSCILLOSCOPE SPECTRUM ANALYZER HP 8642A B SYNTHESIZED SIGNAL GENERATOR LOW NOISE AMP Figure 4 11 SSB Phase Noise Test Setup rev 08JUL88 Performance Test 11 4 35 Performance Tests Model 8642A B NOTE This test is a good ouerall check of the phase noise performance of the HP 8642 However if it is necessary to check phase noise at a specific output frequency perform Performance Test 12 or use an HP Phase Noise Measurement System to verify the performance Equipment epo T I pe ve mE EM D A S ORE DN Padi tpa HP 10514A 1 MHz Low Pass Filt r orriren Leno Ree RE REESE RR RR E E See Figure 1 1 Low Noise Amplifier W Power Supply HP 6216A HP 08640 60506 Spectrum Analyzer eer Ie eher ph eee daw FRE de ewe bee UR Wasa HP 8566A B Oscilloscope e eure Ta e RP VR REDE eg petat HP 1980B Procedure 1 Connect the instruments as shown in Figure 4 11 Preset the instruments Insure that the spectrum analyzer center frequency calibration is accruate 2 On the HP 8642 enter SPCL 8 Set the HP 8642 to 10 020 MHz and 50 dBm amplitude 3 Set up the Spectrum Analyzer a
333. tions a Subtract the reading from step 4 to convert the reading to units of dBc b Add 63 5 dB 50 dB for 8642 attenuator change 10 dB for 1 Hz bandwidth normalization 6 dB for single side band conversion 2 5 dB to correct for the Log shaping and average detection 4 40 Performance Test 12 rev 08JUL88 Model 8642A B Performance Tests Performance Test 13 EXTENDED PULSE TESTS Specification Electrical Characteristics Performance Limits On Off Ratio 30 dB gt 80 dB band 10 Rise Fall Time gt 0 40 us 10 to 9096 of final value Rate 50 kHz maximum Pulse Width 6 us minimum Trigger Level 1 5 volts nominal Description Rise and Fall Time are measured directly on an oscilloscope after video feed through is removed by the HPF and pulse demodulated by the detector On Off ratio is a dynamic measurement of the power ratio of the RF signal during pulse high and pulse low conditions HP 8642A B SYNTHESIZED SIGNAL GENERATOR anon a eur a OB OO OODODO DO OO RF RF SPECTRUM D BEBEBBBBH J LOUTPUT _ SETUP A ANALYZER O onpa AM PULSE INPUT DETECTOR CHANNEL B Figure 4 13 Pulse Test Setup Equipment Oscilloscope erreneren Od Ue hua boa ieee Cah Baie OPERE HP 1980B Function Generator ra susu RR De enum Rex enn reta e esses oa lene Re HP 8116A Spectrum Analyzer es ee Ceo o UR uqa S AQUAE ha NIV ea aware e ACRES c n HP 8566A B Detector 2 2 wv eda hss sea bb phe RR
334. tions Implemented Maximum sweep time 999s Minimum sweep time 5 ms Maximum and minimum sweep time are also dependent on end point separation and fre quency band selected 0 to 10 Vdc 1096 TTL positive true for crt display blanking during retrace Hewlett Packard Interface Bus HP IB HP IB is Hewlett Packard s imple mentation of IEEE Standard 488 1978 All functions controlled from the front panel with the exception of the power switch and the knob are programmable with the same accuracy and resolution as in manual mode Settable via the front panel or over HP IB from 00 to 30 5 bit decimal equivalent A listen only mode is also available as 31 Listener talker and controller SH1 1 6 L3 LEO SR1 RL1 PPO DC1 C1 C2 C28 E2 Mode 8642A B General Information Table 1 2 Supplemental Characteristics 1 of 2 Supplemental characteristics are typical but non warranted performance parameters intended to be useful in instru ment applications FREQUENCY Underrange 10 to 100 kHz Heterodyne Mode HET Special Function 8 The 8642A B can derive its output through a heterodyne mode in the carrier frequency range from 0 1 MHz to 132 1875 MHz This improves modulation and some frequency sweep characteristics at lower carrier frequencies Frequency Switching Time to Within 100 Hz of Final Frequency Processor Delay Frequency Settling Tota Time SPECTRAL PURITY SSB Ph
335. to Clear page 3 24 in the HP IB portion of this Section HI MAXIMUM OF 10 DIGITS E19 4019 This message is never displayed locally HP IB The Signal Generator ignored some digits in the entry Only send 10 digits including significant leading zeros NUMBER OUT OF RANGE E20 4020 The attempted setting exceeds a numeric value which can be represented internally as a number Select a value within the Signal Generator s settable range AMPTD LIMITS MAX AM E24 4024 The amplitude setting limits the maximum AM setting Reduce either the amplitude setting or the attempted AM setting and try again Refer to Table 3 18 page 3 102 for information on setting limitations due to amplitude or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section H3 AM LIMITS MAX AMPTD E25 4025 The AM setting limits the maximum amplitude setting Reduce either the AM setting or the attempted amplitude setting and try again Refer to Table 3 18 page 3 102 for information on setting limitations due to amplitude or refer to the Sequence Dependency discussion that begins on page 3 12 in the HP IB portion of this Section III ONLY INT EXT DC PULSE E26 4026 Only an internal or external dc source is possible with pulse modulation With pulse modulation select only INT or EXT DC For other modulation sources select the modulation type of CAM CEM or CSHET J before selecting the modulation sou
336. tor returns to local control when it receives the Local or Clear Lockout Set Local message The Signal Generator also returns to the local mode when the front panel LOCAL key is pressed provided Local Lockout is not in effect If the instrument is not in local lockout mode nressing the front panel LOCAL key could interrupt a data transmission ana suspend the Signal Generator in an unknown state Refer to Local Lockout Set Local on the following page for more information on the Local Lockout function Operation lt gt Local Lockout Clear Lockout Set Local Model 8642A B LOCAL LOCKOUT SET LOCAL The Local Lockout message is the way the controller sends the Local Lockout LLO bus command The Signal Generator responds to the Local Lockout message by disabling the front panel LOCAL key The Clear Lockout Set Local message is the way the controller sets the Remote Enable REN bus control line false The Signal Generator returns to local mode when it receives the Clear Lockout Set Local message No instrument settings are changed by the transition from remote to local When in local lockout the Signal Generator can be returned to local only by the controller using the Local or Clear Lockout Set Local messages or by setting the Power switch to Standby and back to on or by removing the bus cable NOTE Return to local while in local lockout can be accomplished by switching the POWER J from STBY to ON Retur
337. troller s point of view The service request SRQ line is a signal line on the HP IB interface This line is pulled low by the Signal Generator when it is requesting service Refer to page 3 27 The SRQ annunciator in the display of the 8642A B indicates that this Signal Generator is pulling the HP IB SRQ line low 3 35 Model 8642A B RF FREQUENCY CONTENTS Figure 3 6 RF Frequency Related Functions RF FREQUENCY Table 3 10 RF Frequency Operating Characteristics Table 3 11 RF Frequency Band Ranges FREQ S n REL LAN E d eec ius How to Set RF Frequency nop RE Ue E DER URS How to Select the Het Band Special Function 8 HP IB Codes ciTe Comments Related Special Functions 240 Decrement Frequency by 0 1 Hz 241 Increment Frequency by 0 1 Hz 242 Phase Decrement 1 Degree 243 Phase Increment 1 Degree 244 Phase Decrement 5 Degrees 245 Phase Increment 5 Degrees 250 Phase Adjustment from Knob and Step Up Step Down Keys RELATIVE RF FREQUENCY REL ZERO ood REIS How to Set the Current Output Frequency Setting to Be the Frequency Reference REF SET oce rte rre npe RECTE How to Set a Reference to a Specific Frequency How to Reference to the Signal Generator s Last Selected Reference
338. ts affected by pre emphasis 3 105 EXT AC EXT DC 3 108 External modulation 3 110 Harmonic distortion 3 115 INT 3 107 Low residual 3 112 Maximum stereo separation 3 112 3 116 Mixed modulation 3 101 3 124 Modulation restrictions with other functions 3 110 Pre emphasis 3 113 FREQ 3 40 Frequency reference Display the 3 46 Range of settings 3 47 Turn it off how to 3 47 Frequency sweep 3 49 AUTO sweep setting limitations 3 51 Modulation types not possible during 3 64 Step size 3 49 3 52 Sweep time common to all sweeps 3 64 3 92 Sweep time how to set 3 52 3 86 X Axis steps 3 60 Zero span 3 65 Frequency 3 39 How to set 3 39 3 40 Overranging 3 42 Phase adjust 3 42 Resolution of 0 1 Hz 3 42 Switching time 3 39 Underranging 3 42 FRQ SWEEPING abbreviation 3 49 Function 3 199 G Gl 3 199 995 3 209 Index H HELP 3 167 Heterodyne band 3 39 3 200 Advantages 3 40 Affects AM rates 3 42 Affects FM deviation 3 40 Affects frequency sweep span 3 40 Affects deviation 3 40 How to select 3 41 HI annunciator 3 98 3 108 3 122 HOLD 3 143 HP IB 3 5 8642A B controller capabilities 3 31 Abort 3 31 Active function output 3 18 Annunciators 3 31 Available addresses 3 8 Capabilities from the local mode 3 9 Capabilities 3 9 Capability Reference Table 3 10 Clear lockout 3 26 Clear 3 24 Clearing status bits 3 24 Codes 3 32 Data entry notation 3 14 Data Input Example 3 1
339. tt Packard Company will at its option either repair or replace products which prove to be defective For warranty service or repair 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 HP 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 maintenance NO OTHER WARRANTY IS EXPRESSED OR IMPLIED HP SPECIFICALLY DISCLAIMS THE IMPLIED 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 ag
340. ttempting those settings because Special Function 123 Phase Continuous Frequency Sweep is the type of frequency sweep currently selected Refer to RF Frequency Sweep page 3 49 for more information Turn off either START FREQ J or STOP FREQ and then try your setting again HP IB Turn off the frequency sweep with FAOF or FBOF then retry settings SP9 AM LIMIT MAX AMPTD E9 4009 Special Function 9 Attenuator Range Hold selected with the current AM setting limits amplitude levels attainable according to Table 3 15 refer to Amplitude page 3 75 Turn off Attenuator Range Hold with Special Function 209 and or reduce AM to a depth that will allow the amplitude setting or refer to Sequence Dependency which begins on page 3 12 in the HP IB portion of this Section FUNCTION OFF NO STEP E10 4010 The active function is off so its value cannot be stepped Turn on or set the active function to a valid setting before using the Step keys FUNC DISALLOWS OFF ON E11 4011 The active function cannot be turned off or on You attempted to turn off or turn on either FREQ MOD FREQ J or sweep TIME CSHET START FREQ HP IB codes FR MF or ST Refer to Modulation Oscillator page 3 131 for a way to effectively turn off the internal modulation oscillator ONLY OFF ON IS ACTIVE E12 4012 Only the COFF ON key can be selected Select an active function other than PULSE SHEET EMF CSHET CINCR SET J or KNOB HOLD CSH
341. tude setting when Special Function 9 was selected Figure 3 9 on page 3 76 is a graphic summary of this table Refer to Table 1 1 page 1 7 for AM and output amplitude specifications The following functions are not possible when Attenuator Range Hold is enabled ALC Off Special Function 4 Pulse Modulation and Amplitude Sweep 209 Attenuator Range Hold Off This special function turns off Attenuator Range Hold that 1s selected with Special Function 9 119 Disable Settling This special function allows the Signal Generator s microprocessor to respond to new commands without waiting for the internal circuitry to settle When using this special function it s possible to select a function before the previous function has finished settling When settling is disabled response time is improved by up to 40 ms Special Function 119 disables out of lock messages 219 Re enable Settling This special function re enables the settling that is disabled when Special Function 119 is selected Refer to Relative Amplitude page 3 77 for information on setting amplitude in units other than dBm V mV uV dBuV EMF V EMF mV EMF uV or dB EMF uV Refer to Amplitude Sweep page 3 83 for information on selecting an amplitude sweep range up to 30 dB Refer to Knob page 3 141 and Step Increment Set page 3 149 for information on using these to modify settings Refer to Instrument Preset Partial Preset page 3 139 for information about set
342. tus Byte was cleared or since the last time OC was executed Then reading a Parameters Changed message using OC will enable you to read out only the first message FR SWP PULSE TURNED OFF Cl 2001 RF frequency sweep with pulse modulation was turned off Either START AMPTD or CSTOP AMPTD was selected HP IB AA or AB when RF frequency sweep was on with pulse modulation AMPTD REF SET TO 1 00UV C2 2002 Amplitude reference was set to 1 00 uV The amplitude reference was set to the dBuV reference which is 1 00 uV due to the selection of dBuV HP IB DU Subsequent amplitude displays will be in dBuV ADJUSTED 002UV RESOL N C3 2003 Amplitude setting was adjusted to 0 002 uV resolution In EMF mode if an attempt is made to set an increment or amplitude reference with an odd number of nanovolts for example 0 501 0 503 0 505 uV etc that value will be adjusted up to an even number of nanovolts INCR AMPTD REF CHANGED C4 2004 The increment setting and amplitude reference were changed Changing between EMF and non EMF amplitude modes could cause the increment and amplitude settings to be reset to allowable values AM TURNED OFF C11 2011 AM was turned off Either START AMPTD STOP AMPTD J or PULSE CSHFT CAM was selected HP IB codes AA AB or PL when AM was on AM is not possible with pulse modulation or ampliltude sweep FM TURNED OFF C12 2012 FM was turned off was selected when FM was on FM cannot be do
343. umbers less than 200 Clears any uncompleted HP IB messages Selects RF Frequency as the active function Selects RF OFF which does not change the output attenuators but maintains the last selected value as the on setting that can be selected with the OFF ON key HP IB Codes Keys Codes El EA PARTIAL Comments Bypassing the Power Up Self Check The Signal Generator takes aproximately 20 seconds to perform the initial checks done when is switched from STBY to ON This time delay can be avoided and these checks can be bypassed by holding down the CSHIFT_ key during turn on First hold down the CSHIFT key then switch to ON holding CSHIFT until instrument settings are displayed rev 20MAR 85 3 139 Model 8642A B Description Procedures Operation KNOB The Knob isa variable stepping control It actually changes the active function in steps that are determined either by 1 the cursor position and the rate at which you turn the Knob or 2 the increment set value if the Knob Increment function is selected The Knob can control the following functions Frequency Start Frequency Stop Frequency Amplitude Start Amplitude Stop Amplitude AM Depth FM Deviation Deviation Modulation Frequency Modulation Output Sweep Time Manual Sweep for either amplitude sweep or frequency sweep Help Phase on Knob and Step keys Special Function 250 Knob Hold enables the Signal Generator to fix the Knob
344. unctions will be turned off when another FM modulation source is selected 205 External Low Rate FM Off This special function turns off the FM modulation source selected with Special Function 5 When Special Function 5 is turned off in this way the Signal Generator selects external ac coupled FM 3 112 Model 8642A B Operation Modulation FM cont d 212 Internal External Low Rate FM Off This special function turns off the FM modulation source selected with Special Function 112 When Special Function 112 is turned off this way the Signal Generator selects internal and external ac coupled FM summed together 6 FM Pre emphasis On Special Function 6 can be selected to pre emphasize internal or external FM modulating signals with a 750 us time constant Pre emphasis boosts high frequencies in the modulating signal prior to modulating the carrier The Signal Generator s FM pre emphasis creates some restrictions on the allowed combinations of modulation frequency and maximum deviation See Figure 3 14 on page 3 114 for FM deviation limits that apply when pre emphasis is selected with the internal modulation source Table 3 21 on page 3 115 is to be used in conjunction with Figure 3 14 to calculate the maximum deviation possible The maximum deviation depends on the RF frequency band and the modulation frequency selected See Figure 3 14 The FM deviation is on the Y axis in the graph The values of deviation are shown for Band 9 a
345. unlocked VCO With Special Function 118 selected the input signal is ac coupled to the unlocked FM VCO blocking any applied dc component Typical low frequency corner frequency is 1 Hz Using DC FM avoids the phase shifts associated with ac coupled FM circuitry and allows maximum stereo separation An external FM source must be in use with Special Function 118 to get these benefits 218 AC Coupled DC FM Off This special function re selects the dc coupling to the FM circuitry disabled with Special Function 118 119 Disable Settling This special function allows the Signal microprocessor to respond to new commands without waiting for the internal circuitry to settle When using this special function it s possible to select a function before the previous function has finished settling When settling is disabled response time is improved by up to 40 ms Special Function 119 disables out of lock messages 219 Re enable Settling This special function re enables the settling that 1s disabled when Special Function 119 is selected 248 Calibrate the Modulation Frequency Bands Again This special function enables you to initiate the calibration sequence that normally only occurs during instrument power up This function can be used for example to recalibrate the modulation oscillator frequency bands if normal modulation frequency correction has been disabled with Special Function 113 Calibration typically takes one to two s
346. urce select any of the following modulation types CAN SHFT EM or PULSE CSHFT HP IB Specify the modulation type code AM FM PM or PL before the modulation source prefix code NT XA XD BA or BD SELECT SWP PREFIX FIRST E5 4005 Select the type of sweep first A sweep mode auto manual or single was selected without specifying the sweep type frequency or amplitude sweep Select START FREQ STOP FREQ J START AMPTD or STOP AMPTD before selecting the sweep mode HP IB Specify the sweep type code FA FB AA or AB before the sweep mode code SA SM or SG PLEASE SELECT FUNCTION E6 4006 Please select an active function A data value was attempted during manual sweep or when no active function existed Select a valid function before attempting to enter a data value HP IB Precede the data entry with a function prefix code 3 184 Model 8642A B Operation Operating Messages cont d SP6 PREVENTS INT EXT FM E7 4007 Special Function 6 FM Pre Emphasis On prevents the selection of a summed internal and external FM source Select Special Function 206 FM Pre Emphasis Off to select INT EXT AC INT EXT DC or Special Function 112 Internal External Low Rate FM Refer to Modulation FM page 3 113 for more information HP IB Select SP206 before selecting FM source codes FMBA FMBD or SP1 12 TURN OFF SWP FIRST SP123 E8 4008 Turn off the frequency sweep before a
347. urer s Name Hewlett Packard Co Manufacturer s Address Spokane Division 24001 E Mission Avenue Liberty Lake Washington 99019 9599 USA declares that the product Product Name Signal Generator Model Number HP 8642A and HP 8642B Product Options This declaration covers all options of the above product conforms to the following Product specifications Safety HD 401 IEC 348 EMC CISPR 11 1990 EN 55011 1991 Group 1 Class A IEC 801 2 1984 EN 50082 1 1992 4 kV CD 8 kV AD IEC 801 3 1984 EN 50082 1 1992 3 V m IEC 801 4 1988 EN 50082 1 1992 0 5 kV Sig Lines 1 kV Power Lines Supplementary Information The product herewith complies with the requirements of the Low Voltage Directive 73 23 EEC and the EMC Directive 89 336 EEC Safety qualification of this product was performed 10 5 89 Report no SA8642 89 Spokane Washingtion USA October 2 1995 U e RG Date Vince Roland Quality Manage European Contact Your local Hewlett Packard Sales and Service Office or Hewlett Packard GmbH Department ZQ Standards Europe Herrenberger Strasse 130 D 71034 B blinger Germany FAX 49 7031 14 3143 NOTE During operation of the HP 8642A B a 4 kV contact electrostatic discharge to AM Pulse Input or Modulation Input ports may cause temporary degradation of performance requiring operator intervention Model 8642A B Installation SECTION II INSTALLATION 2 1 INTRODUCTIO
348. urned off individually Refer to page 3 169 111 Disable the Automatic Special Function Verification Display This special function disables the automatic display of the special function description that normally occurs after each special function 15 selected 3 172 Model 8642A B Operation Special Functions cont d DETAILED DESCRIPTIONS OF ALL SPECIAL FUNCTIONS cont d 112 Internal External Low Rate FM On 5 External Low Rate FM On These special functions typically provide 0 4 Hz to 200 kHz external ac coupled FM with the Signal Generator remaining in a phase locke state Input coupling required for these functions makes the Signal Generator especially sensitive to dc voltage fluctuations Therefore relatively small dc voltage changes can cause the Signal Generator to lose phase lock requiring one to two seconds to regain the locked condition Special functions 112 or 5 is turned off when another FM modulation source is selected 113 Modulation Frequency Correction Off This special function disables the single band calibration of the modulation frequency oscillator that normally occurs whenever the modulation oscillator frequency is set or the internal modulation oscillator is put into use When this calibration is disabled the typical modulation frequency switching time is decreased by approximately 200 ms Refer to Modulation Frequency page 3 133 for a discussion of modulation frequency accuracy with Special Function 113 s
349. utput using OH Refer to the Output Messages discussion that begins on page 3 16 in the HP IB portion of this Section III and to Hardware Error Messages on page 3 193 Solutions 1 Either reduce the amplitude level reduce the AM depth or reduce the external modulation input level 2 Either reduce the FM or deviation reduce the modulation frequency select Special Function 8 Prefer Heterodyne Band change the external modulation rate or change the external modulation level 3 Either the external reference is not operating properly or connections are faulty at the rear panel connector EXT REF INPUT The internal hardware may still be faulty even though the message is gone that is the message would appear again if you connected another external reference to the instrument 3 197 Operation Operating Messages cont d 3 198 OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE OUT OF LOCK ERROR TRANSIENT FAILURE Model 8642A B Table 3 29 Out of Lock Messages Message D1 F0 F1 Doubler ALC loop is out of lock Doubler ALC loop had been out of lock but now appears to be in lock Internal hardware cannot phase lock to the ex te
350. uyu 2 p a ee ae RYE TUR 3 5 HPIBRemoteOperat on i31 ku eR ree He bue WIR e xr RR EORR IURE edes 3 7 uuo ate SCR Ro e ete eos aha S verter A duce ae eee sby eds 3 8 HP IB Capabilities Sg pa o alor uri as deco dette ae a Rad as ai e CRE ua 3 9 Data Input Bj teu eat adie gee aed tue EUER US Rue Rat PP e lee up 3 11 Data Output o ioa x Rex S LE Vues aK ep Ree bisce Uam CRUEL TG AQ LR dde 3 15 Clear QUUM weds Salar ERN E BES a TRI Nue ise vienes SC IUE eae Se 3 24 Remote aye s gre Ed Cot ge tae fe oes A as Glad SI oe ee ae 3 25 Local Lockout Set Local rome cun yupa SE Ae SES a SAS ORE He Re eee Rx 3 26 Service Request 3 k sos eet ari howe du Uy a Sahara debe RR Blane ee Poe a es 3 27 Status Byte c nouus dogs tye nt ac Sa Eaton es dc late es ao aloe 3 29 Additional HP IB Information 3 31 HP IB Codes Summary s i 9e Dee W OE E XR BW e k K Q Ua k oae m RU RU RO US 3 32 HP IB Related Front Panel 3 34 HP IB Related Terms 2 2 ute dob late me on PURGE SUR BUS E NUR 3 35 RE Frequency gira hp Ae Hoh bot Eaotexed vere on og e RUE G s 3 37 RE Frequency Contents o s ecne q k mb SUS
351. vels lt 15 dBm 8642A B Bands 1 9 HET 8642B Band 10 10 to 9096 External dc Into 600 ohms 0 02 kHz to 15 8 kHz 215 8 kHz Within 1s Maximum deviation may be increased up to that shown for the HET band 0 1 MHz to 132 1875 MHz carrier frequency by selecting deviation larger than the values shown here HET band can also be selected with Special Function 8 SOutput level accuracy is typically 3 dB rev 16M AY 86 Model 8642A B General Information Table 1 1 Specifications 5 of 6 Electrical Characteristics Performance Limits Conditions GENERAL Operating Temperature Range Storage Temperature Range Power Requirements Line Voltage Line Frequency Power Dissipation Electromagnetic Interference Leakage Net Weight Shipping Weight Dimensions Height Width Depth HP SYSTEM II Module Size Electrical Characteristics Characteristics Digitally Sweep Start and Stop Sweep Phase Continuous Sweep Start Stop Sweep Maximum Sweep Span Band 10 8642B only 9 0 to 55 55 to 75 C 100V 120V 220V or 240V 47 5 to 440 Hz 300 VA max MIL STD 461B and FTZ 1115 1596 1096 Conducted and radiated interference is within the requirements of MIL STD 461B methods CE03 and REO2 Interference is also within the standards set by FTZ 1115 Also RF leakage of 0 5 uV is in duced in a two turn loop 2 5 cm in diameter held 2 5
352. ven in the table rev 08JUL88 below 2 Verify that the distortion readings on the audio analyzer are less than the specified maximums given in the table below Results Actual Distn Max Performance Test 6 4 23 Performance Tests Model 8642A B Performance Test 7 INTERNAL MODULATION OSCILLATOR TESTS Specification Electrical Characteristics Performance Limits FREQUENCY Range Resolution Accuracy OUTPUT LEVEL Range Resolution Accuracy Distortion 20 5 volt peak Output Impedance 20 Hz to 100 kHz 196 of setting 296 of setting 0 to 3 volts peak 600 ohm load 4 mV 4 setting 15 mV within 1 second 0 0276 0 02 to 15 8 kHz 0 15976 215 8 kHz 600 ohms 10 Description Internal Modulation Oscillator specifications are checked by measuring the specified parameters on an audio analyzer HP 8642A B SYNTHESIZED SIGNAL GENERATOR FEEDTHROUGH TERMINATION Figure 4 7 Internal Modulation Oscillator Test Setup 4 24 Performance Test 7 rev 08JUL88 Model 8642A B Performance Tests Equipment Audio Analyzer yQ eu XS LEE a rt edu SU eet e isis s ass HP 8903A Feedthrough Termination 600 ohm HP 11095A a 600 ohm 1 resistor to ground can be substituted Use HP part number 0757 1100 or 0698 4015 Procedure Setup 1 Connect the instruments as shown in Figure 4 7 Setup A 2 Preset the HP 8642 and audio analyzer
353. was attempted before the AM setting AM could be changed first to achieve the setting but setting AM first would not always be successful For example if you were changing back to the first example to an amplitude of 14 dBm and AM depth of 99 setting the AM first would not set the requested AM setting To eliminate this sequence dependency problem when setting AM or amplitude first turn off AM then set the amplitude then set the AM depth How to Avoid Sequence Dependency Problems The Detailed Operating Instructions in this Operating Manual describe the limitations of specific coupled functions and will help you avoid entering incorrect sequences Also when operating locally displayed Execution Error messages direct you to your entry error However if operating via HP IB it might be inconvenient to rely either on the manual or on error messages for every combination of settings Flowcharts of Sequence Dependency on the following page can assist in the development of driver subprograms to eliminate the consequences of sequence dependency If you follow the flowcharts and still cannot obtain the requrested setting that setting is probably not possible Model 8642A B Operation lt gt When setting one or more of the following use the appropriate flowchart FM PM FMOF PMOF FR FR FM Source PM Source MF if source is FMNT FMXA or SP112 SP6 num SP8 SP208 SP205 SP212 ALREADY CONLIGURED FOR NO 0 THE DESIRED
354. wed may require up to 10 days rev 0O8JUL88 Performance Test 15 4 47 Model 8642A B Performance Test Record Performance Test Record Performance Test 1 Level Accuracy and Flatness Tests 8642 FREQ Measuring Receiver Results Frequency dBm HET Band Level Accuracy 50 12E 03 79 43E 03 7 762E 03 12 30E 03 2 510E 03 3 981E 03 794 3E 06 1 259E 03 79 43E 06 125 9E 06 7 943E 06 12 59E 06 rev 08JUL88 4 49 Performance Test Record 4 50 HP 8642 AMPTD dBm 8642 FREQ MHz Oo G Q 000000 QOO WWWHO G G GO GO Measuring Receiver Frequency MHz G OU 000 Measuring Receiver Mode RF POWER RF POWER RF POWER TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF RF POWER RF POWER RF POWER TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF TUNED RF 79 43E 03 7 762E 03 2 510E 03 0 794E 06 79 43E 06 7 943E 06 794 3E 09 79 43E 09 7 943E 09 794 3E 12 79 43E 12 7 943E 12 794 3E 15 79 43E 15 7 943E 15 794 3E 18 158 5E 18 79 43E 03 7 762E 03 2 510E 03 794 3E 06 79 43E 06 7 943E 06 794 3E 09 79 43E 09 7 943E 09 794 3E 12 79 43E 12 7 943E 12 794 3E 15 79 43E 15 7 943E 15 794 3E 18 158 5E 18 Model 86424 B Results watt
355. weep has indeed been selected access the SPCL display CSHFET Press the SHIFT key twice to return the display to the current instrument settings if desired You can turn off the Phase Continuous Frequency Sweep mode by first stopping the actual sweep for example with OFF ON HP IB codes AOF and FBOF and then by selecting Phase Continuous Frequency Sweep Off Special Function 223 Operation Model 8642A B RF Frequency Sweep cont d HP IB Codes Comments 3 64 START FREQ STOP FREQ SWEEP TIME AUTO MANUAL SINGLE OFF ON FAOF FBOF FAON FBON Sweep Time Is Common to All Sweeps Sweep time is common to amplitude sweep and frequency sweep If sweep time is not specified the Signal Generator assumes the value last selected for either amplitude or frequency sweep If this last selected sweep time value is below the minimum setting allowed under current conditions the message SWEEP TIME ADJUSTED C21 is displayed and sweep time is automatically set to the minimum allowed setting Phase Continuous Frequency Sweep Miscellaneous Information During Phase Continuous Frequency Sweep Special Function 123 sweep span and sweep time limitations depend on which frequency band is being used The frequency band being used is the center frequency of the sweep which is one half of the sum of the start frequency plus the stop frequency The start or stop end point could be outside the band being used Ch
356. weeps from a start end point to a stop end point in linearly spaced incremental steps Phase Continuous Frequency Sweep Special Function 123 sweeps from a start end point to a stop end point in a linear phase continuous manner Sweep step size is automatically selected based on the frequency span which is the absolute value of the start frequency minus the stop frequency and the sweep time Although step size for the Stepped Frequency Sweep cannot be directly set this operating instruction provides ways to calculate a sweep t me o enable you to select a particular step size or number of steps Table 3 12 RF Frequency Sweep Operating Characteristics Electrical Characteristics Performance Limits Conditions Digitally Stepped Frequency Sweep Range Time Phase Continuous Frequency Sweep Maximum Sweep Span X Axis Output Z Axis Output 0 100000 to 1057 500000 MHz 0 100000 to 2115 000000 MHz 275 ms minimum 999s maximum 800 000 kHz 8642B only 400 000 kHz 200 000 kHz 100 000 kHz 50 000 kHz2 25 000 kHz2 12 500 kHz2 6 250 kHz2 3 125 kHz2 25 000 kHz2 400 000 kHz 5 ms minimum 999s maximum Maximum and minimum sweep times are also dependent on the sweep span and carrier frequency 0 to 10 TTL Positive True End points can be outside the band but Start Frequency Stop Frequency 2 must be within the band 1057 500001 to 2115 000000 MHz 528 750001 to 1057 500000 MHz 264 375001 to 528 7
357. y 2 HP 8642B only Incidental PM 1 Set the HP 8642 AM to 30 2 Set the measuring receiver to PM mode and leave the 300 Hz HP filter and 3 kHz LP filter enabled 3 Set the HP 8642 RF Frequency to the values listed in the table below and verify that the measuring receiver readings are within the specified limits HP 8642 FREQ MHz 8 0000 0 20 rad 10500 0 20 rad 1300 2 0 20 rad 1 HP 8642A 2 HP 8642B 4 18 Performance Test 5 rev 08J UL88 Model 8642 A B Performance Tests AM Distortion 1 2 Set the measuring receiver back to AM then to audio distortion mode Set the HP 8642 RF frequency and AM depth to the values listed in the table below and verify that the measuring receiver readings are within the specified limits HP 8642 AM FREQ 0 15 0 15 0 15 1050 105000 10500 130002 1300 2 13000 500 500 500 1 HP 8642A only 2 HP 8642B only PM Indicated Accuracy and Distortion 1 na to rev 22AUG90 Set the measuring receiver to PM mode with the 300 Hz HP filter and the 15 kHz LP filter selected Select PEAK detector on HP 8902A Turn off the HP 8642 AM Set the RF frequency and PM deviation to the first values in the table below Verify that the measuring receiver reading for phase deviation is within the specified limits Set the measuring receiver to distortion mode and verify that the distortion reading does not exceed maximum
358. y MHz Results Performance Tests 13 Extended Pulse Tests ame Frequency ts we non 1000 0 30 0 2000 0 45 0 Performance Test 14 Optional Resisdual FM Tests 8642 e Performance Test 15 Internal Time Base Aging Rate Test Option 001 oniy 1 x 107 day 4 60 rev 08JUL88 Model 8642A B Adjustments Section 5 ADJUSTMENTS Table of Contents op eMe eres PAS eb WE PR Auto Adjust Routines reee mesih ai eia TRO Y eS Mie dg wee s Ue WL RE Y RR ch S Description Jed eR su ate ivei ed ce ER dy ae og adt S Qa How Auto Adjust Procedures Begin 0 0 et een hr as as Correction Data Special Functions lesse ee re Identifying the Contents of A202 0 ioc cc ehh hh hen Identifying the Contents of sN usia aus kaa ehh ahh he Interpreting Cal Data Stats l lu aaa ye aa e ate Adjustments Model 8642A B 5 1 ADJUSTMENTS If a repair is done by the Module Exchange method no adjustment of the HP 8642 or the exchange module is necessary If a component level repair is performed on a module it will be necessary to do its Manual Adjustments and or Auto Adjust Procedures to ensure its I O spec s Due to the modular nature of the HP 8642 the adjustment of a module will not effect other modules in the instrument After the repair of a module it i
359. y have a serial prefix that is not listed at the beginning of Volume 1 An unlisted serial prefix number indicates that the instrument differs in some way from those documented in this manual A MANUAL UPDATES packet is shipped with the manual when necessary to provide you with the most current information available at the time of shipment These packets consist of replacement and addition pages which should be incorporated into the manual to bring it up to date Hewlett Packard offers a Documentation Update Service that will provide you with further updates as they become available If you operate or service instruments of different serial prefixes we strongly recommend that you join this service immediately to ensure that your manual is kept current For more information refer to the Documentation Update Service reply card included with this manual or contact Hewlett Packard Company Spokane Division Technical Writing Department 24001 E Mission TAF C 34 Spokane WA 99220 509 922 4001 rev 3OSEP88 Mode 8642A B Genera Information Electrical Characteristic FREQUENCY Range HP 8642A HP 8642B Table 1 1 Specifications 1 of 6 100 kHz to 1057 5 MHz 100 kHz to 2115 MHz Carrier Frequency Band 10 8642B only 1057 500001 2115 000000 MHz 528 750001 1057 500000 MHz 264 375001 528 750000 MHz 132 187501 264 375000 MHz 66 093751 132 187500 MHz 33 046876 66 093750 MHz 16 52
360. yed AM depth With an external 1 Vpk signa applied the Signal Generator modulates its RF output to achieve the modulation depth setting For example if a 1 Vpk external modulation source is provided with the Signal Generator s AM depth set to 50 0X per volt the output has 50 0 modulation depth If the source voltage is reduced to 0 5 Vpk and no other settings are changed the output has 25 modulation depth If the HI and LO annunciators are not displayed then the external modulation signal is between 0 95 Vpk and 1 05 VPk The HI LO annunciators only apply to sinewave inputs The HI LO detectors do not monitor dc voltage input levels External Coupling Any one of the following functions can be used to couple the external AM PULSE INPUT to the AM circuitry AC Coupled Source e EXT AC This function selects the external ac coupled AM source displaying the EXT and AC annunciators INT EXT AC CSHFT EXT AC This function selects the external ac coupled AM source and internal AM source summed together displaying the INT EXT and AC annunciators DC Coupled Source e EXT DC This function selects the external dc coupled AM source displaying the EXT and DC annunciators INT EXT DC CSHET EXT DC This function selects the external dc coupled AM source and internal AM source summed together displaying the INT EXT and DC annunciators Rate Determined by the external modulation source frequ
361. ze in dB Operation Model 8642A B Amplitude Sweep cont d Example for Calculation 4 Set an amplitude sweep from 10 to 10 dBm with a sweep step size of 0 8 dB Calculate the required sweep time setting for a 0 8 dB step size using calculation 4 Ensure that an integer results when the amplitude span of 20 dB is divided by the step size of 0 8 dB 20 dB _ 0 8 dB Minimum step size is equal to 0 1 dB Maximum step size 15 equal to the maximum of 0 1 dB or 10 dBm 10 dBm _ 5 4 dB Since 4 dB is greater than 0 1 dB the maximum step size is 4 dB Therefore it should be possible to select a 0 8 dB step size since that value is between the minimum value 0 1 dB and maximum value 4 dB To obtain a step size of 0 8 dB you can set the sweep time between the results of the following calculations 0 8 dB 3 ms 78 ma dBm 10 28 12 dBm 10 gBml oly 4 ms 81 ms 0 8 dB SWEEP SWEEP AUTO TIME START START START AMPTO AMPTD FREQ SWEEP START STOR AMPTD AMPTD program codes AASA ST 80 MS AA 10 DM AB 10 DM Model 8642A B Operation Amplitude Sweep cont d Example for Calculation 4 cont d Display fA A FA TATA TA TA mi 7 FA rA AR Ti I 1 Xd I FA Ti rm t ud hf FREG SWPNG START AMPTD STOP The display usually shows the start amplitude and the stop amplitude settings If a

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