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VM700T Video Measurement Set Service Manual

1. Al NTSC BW 50 kHz Analog Input board _ flatness adjust o 276 gss 2 R146 NTSC BW 50 kHz R304 2 level adjust R138 Chroma Filter R186 flatness adjust C922 p Chroma Filter _ a level adjust TP610 CAL DAC IP R474 p HM R476 25 C335 i board J550 BE Ox J765 MID FREQ R138 Lh TP86 gt lt x PAL VCO adjust gt _ 2 HIGH FREQ NTSC VCO adjust _ gt o Wie U E lt i J2 Padi us TP17 GND Genlock board TP15 CLK TP12 CLK Figure 5 1 Adjustment locations 14 Touch the Zero Set soft key to set the measurement reference for the internal oscillator 15 Connect the signal generator full field and burst to the channel A input terminate the loop through with 75 BNC termination VM700T Video Measurement Set Service Manual 5 5 Adjustment Procedure 5 6 Adjust Filter Flatness 16 Check that the burst frequency measurement is 0 10 Hz using the internal
2. 1 LJ C 3 U c f 1 c a s I 1 7 C 5 ACUME D Horizontal Centering Figure 5 3 Display monitor centering adjustments Vertical Centering 9 After making the adjustment requested and storing the current setting a second set of instructions is displayed as shown in Figure 5 5 Follow the directions given in the screen to calibrate the touch panel to the CRT display TOUCH PANEL INTERFACE CAL DISPLAY Use the knob to adjust horizontal position and squareness of the screen border lines Press AUTO button to abort or any other to accept and store current setting Current Setting 8 Figure 5 4 Touch screen calibration display VM700T Video Measurement Set Service Manual Adjustment Procedure TOUCH PANEL INTERFACE CAL PANEL press AUTO to abort TOUCH THE DOT INSIDE THE SQUARE Place finger tip directly over the dot being careful to avoid parallex Keep touching the dot until the square highlights and beeper sounds SQUARE LOCATIONS SEQUENCE SQUARES will appear near the screen corners SEQUENCE will be 1 2 3 4 as indicated to the right Screen 1 2 3 4 Figure 5 5 Touch scre
3. 1 32 Audio Spectrum Specifications 1 34 Multitone Analyzer 1 35 A V Timing Specifications Option 42 1 36 Option 48 GPIB Specification 1 36 Option 1S SDI Specification 1 38 Installation exe te xt e her estes haee Baa eed s 2 1 Unpacka ginp 3 26 29x ceil a4 Eie e paces aud A REM RE RE 2 1 Power Requirements 222 cr pa mt aie ney stele sie REIR RE 2 1 Changing Line Voltage Range and Fuse 2 2 Power Cod vir Dee xe Ri TG we ETE GERE 2 2 Power Line Conditioner 2 2 Installing the Power Line Conditioner 2 3 Power On Diagnostics 0 0 cece 2 4 Calibrating the Touch Screen 2 5 Setting the Power On Mode 2 7 Measurement Set Operating Modes 2 8 Wavetorm MOde said ii is posa RIS E Ne XX RR eR TEE ENE 2 8 Vector Mode siis Be een Pee Ene ee eR Ee Ee EE eae as 2 9 M asure MOde i ru Pe A eR TR TERE 2 9 Picture Mode e ORANA ENS AA RC SE OR RES EE 2 9 Auto Mode ERE ts cae Ree EE
4. Figure 5 2 VM700T startup menu Figure 5 3 Display monitor centering adjustments Figure 5 4 Touch screen calibration display Figure 5 5 Touch screen calibration panel Figure 5 6 Panel calibration values Figure 5 7 Example gain phase analyzer flatness waveforms Figure 5 8 VM700T startup menu Figure 5 9 Instrument run modes menu Figure 5 10 Loosening the right side cover Figure 5 11 Cable requirements for adjusting the Cable Meter 4 1 4 2 4 3 4 4 4 4 4 16 4 17 4 21 4 22 5 5 5 11 5 12 5 12 5 13 5 13 5 18 5 21 5 21 5 23 5 26 Figure 5 12 Location of CPU board dip switch and SDI board test boni and adjustment resistor Figure 5 13 Adjusting the eye crossing horizontal position Figure 5 14 Adjusting the rising edge of the SDI Eye Diagram application leeeeeeeeeeeeee er hh nnn Figure 6 1 Locating the major standard assemblies Figure 6 2 Removing a cover panel Figure 6 3 Removing the left card cage center support Figure 6 4 Installing the I O board in the card cage Figure 6 5 Locating audio option boards in the left side card cage Figure 6 6 Orientation of the cab
5. Open Q Figure 6 57 Boot switch setting to enable diagnostic output to serial port 0 Setting the Console Baud Rate The baud rate setting for output of the diagnostics through the serial port must be set to match the requirements of the terminal or terminal emulation program used to monitor the output Setting the diagnostic baud rate is done in one of the choices in the Diagnostics Configuration Menu shown in Figure 6 58 Select Set Low Level Diagnostics Baud Rate and press the Select Line button to enter the menu The recommended baud rate setting for most applications is 9600 baud If the display is not working this is the baud rate to try first for viewing the diagnostics information The VM700T is capable of 38800 baud If the display is working you can set the baud rate as high as your terminal or terminal emulation program will handle Be sure to set the baud rate of the terminal to match Low Level Diagnostic Interface knob moves cursor Select Line inputs selection DIAGNOSTICS CONFIGURATION MENU Key Selection P Set Diagnostics POWERUP MODE I Set Diagnostics INTENSITIES B Set Low Level Diagnostics BAUD RATE Reprint Q Abort Menu Input your selection Figure 6 58 Diagnostics Configuration menu VM700T Video Measurement Set Service Manual Troubleshooting Procedures Connecting a Terminal or PC The VM700T has t
6. 3 1 Module Functional Description 3 3 Analog Input Board 1 2 0 0 cee I 3 3 Loop Through Inputs e 3 3 Mode Control sors PR RAM UN CERE feta 3 3 Clamped Input Amplifiers nen 3 3 Clamp and Bias Generator 0 0 eee een 3 3 Channel Selection i soie IRURE ux UR PUE RUE 3 3 Differential Amplifier elseeseeeeee nen 3 5 Dynamic Offset Generator and Offset Amplifier 3 5 Variable Gain Amplifier 2 0 0 0 0 0c cece cc cee cee 3 5 Dither Generator and Dither 3 5 Calibration DAC oia feo aided te pd 3 5 SYDE Sel ctioD t ss Son s alee teases des 3 6 DVM Selection and DVM eens 3 6 The Genlock Board 2 nesre eerten cei e 3 7 cose E A ERR E 3 7 Crystal OSCIIatOE uu t bebo oreet 3 7 EH Generator oov 3 9 Phase Locked Loop PLL 3 9 Divide by 2 Frequency Divider 3 9 Frame Decoder dot Sero duds 3 9 Frame Rate Synthesizer eee eee 3 9 Stripped Sync Processing 0 eee eee ees 3 9 Output Generator ccs oa see rr rr ry E RR EAS 3 10 Control e
7. Figure 6 53 Interactive run mode menu after running first main test DiagsLoop You may at times want to run the user selectable diagnostics continuously Continuous or looped diagnostics are useful if you are looking for intermittent errors The DiagsLoop application is located in the VM700T Diagnostics directory DiagsLoop repeatedly runs the diagnostic routines selected in the Diagnostics Selection file DiagsLoop displays the same level of information as the Power Up Mode of individual diagnostic execution but DiagsLoop does not pause when failures occur Results from all failed tests are written to the Diagnostic Errors file refer to High Level Diagnostic Errors File on page 6 84 To stop DiagsLoop execution press the Abort Looping soft key VM700T Video Measurement Set Service Manual 6 77 Troubleshooting Procedures Diagnostics Selection File The Diagnostics Selection file allows you to specify the high level diagnostics that run during Powerup Diagnostics or Diags Loop When the VM700T is powered on with diagnostics enabled to run not Quick Start the diagnostics selected in the Diagnostics Selection file are run The contents of the Diagnostics Selection file are shown in Figure 6 54 Power Up Diagnostics Selection Genlock Diagnostic Controller Diagnostic Acquisition Diagnostic ADC Diagnostic AnalogInput Diagnostic FilterBoard Diagnostic AudioProcessor Diagnostic AudioAnalog Diagnostic GPIB
8. 4 34 SDEOULDUC 6 o puce iro esteri oe audet te dun ta 4 35 VM700T Video Measurement Set Service Manual Table of Contents Adjustment Procedure Maintenance Options Replaceable Electrical Diagrams Replaceable Mechanical Parts vi Test Equipment Required itet ipi een 5 1 System Adjustment Procedures eee eee cee 5 2 Extended Adjustment Procedure ec cee eee 5 15 Option 1S Adjustment Procedure 5 22 Servicing Preparation eee er E rH ee ee 6 1 Inspection and Cleaning icas riene a cc nen 6 4 Repackaging the Instrument sicn enri viore rit eee en 6 5 Repackaging ville aa a ae a a pr pie 6 5 Removal and Replacement 6 6 VM700T Rack Mounting Instructions 6 44 Troubleshooting Procedures 6 49 Troubleshooting 6 50 Isolating Operational Faults 0 eh 6 51 Diagnostles 5c eee ue obere rice t orent 6 55 Troubleshooting the Power Supply and CRT Display 6 90 Troubleshooting Option 40 and Option 41 6 95 Troubleshooting Option 48 GPIB
9. Audio Option 41 connector pin assignments VM700T symptoms and corrective actions User selectable diagnostics Le Diagnostic test number to hardware components tested cross reference 55555 Table 6 6 Table 6 7 Table 6 8 Table 6 9 Typical communication setup parameters VM700T RS 232 connector pin outs Typical RS 232C null modem cable wiring Power supply trouble indicators Table 6 10 Power supply voltages Table 6 11 Audio Processor board diagnostics Table 6 12 Audio Analog board diagnostics Table 6 13 SDI Option 1 diagnostic test descriptions Table 7 1 Table 7 2 Optional accessories Power cord options 2 20 2 21 3 19 4 6 4 14 4 15 4 16 4 20 4 21 4 25 5 1 5 16 5 19 5 22 5 24 5 25 5 27 VM700T Video Measurement Set Service Manual a General Safety Summary To Avoid Fire or Personal Injury Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it To avoid potential hazards use this product only as specified Only qualified personnel should perform service procedures To avoid potential hazards use this product only as specified U
10. 1 32 Table 1 88 Accuracy and Flatness specifications 1 34 Table 1 89 General Audio Spectrum specifications 1 34 Table 1 90 Audio Spectrum Level measurement specifications 1 34 Table 1 91 Harmonic Analyzer measurement specifications 1 35 Table 1 92 Miscellaneous specifications 1 35 Table 1 93 Multitone Analyzer measurement specifications 1 35 Table 1 94 Audio Video Timing measurement specifications 1 36 Table 1 95 IEEE 488 1 interface functions implemented in the VM700T GPIB interface card 1 37 Table 1 96 GPIB Electrical characteristics esee 1 37 Table 1 97 Mechanical specifications 1 38 Table 1 98 Optional accessories 1 38 Table 1 99 SDI Eye Diagram application 1 38 Table 1 100 SDI Jitter application 1 39 Table 1 101 SDI Wander application 1 40 Table 1 102 SDI Interchannel Timing application 1 40 Table 1 103 SDI Audio Video Timing application 1 41 Table 1 104 SDI Ch A Input 1 42 Table 1 105 SDI Ch B Input 1 43 Table 1 106 LTC Input 1 43 Table 1 107 SDI Output 1 44 Table 1 108 Analog Ref Input
11. 1 44 Table 1 109 AES Audio Input 1 44 Table 1 110 Environmental specification 1 44 VM700T Video Measurement Set Service Manual xiii Table of Contents xiv Table 2 1 Table 2 2 Table 3 1 Table 4 1 Table 4 2 Table 4 3 Table 4 4 Table 4 5 Table 4 6 Table 4 7 Table 5 1 Table 5 2 Table 5 3 Table 5 4 Table 5 5 limits Table 5 6 Table 5 7 Table 6 1 Table 6 2 Table 6 3 Table 6 4 Table 6 5 Audio Option 41 connector pin assignments Status indicators Signals used by VM700T RS 232C ports Test equipment required for verification Test equipment required for verification procedures Accuracy and flatness specifications Example test signals for level and flatness test Accuracy and flatness specifications Example test signals for level and flatness test Test equipment required for Option 1S verification Test equipment required for verification and adjustment Gain phase analyzer setup Gain phase analyzer setup for ADC Test equipment required for Option 1S adjustment SDI Eye Diagram application gain and offset value Jitter application adjustment value limits Cable meter adjustment value limits Static susceptibility
12. 3 35 DSP Processor and I O Interface 3 35 OSCIHatOE oot regt ERR Cere e POS Tere tete ud Steves 3 35 Communication Ports see ee e heh 3 35 Audio Data Register rep Herr XR Rh diate ere RD or pus 3 36 CPU Access Disable o oe tA ott et ER tes 3 36 Statico RAM ta oe er pa A E Fe eta acta 3 36 PEME MOLY v ete rene ete RR Trete edat e he uto CIT e Lea us 3 36 X Data and Y Data Memory 0 cee eee eee eee eee 3 36 Program Loading eor cree pierce wine care eel nie gies wre ael ele eget 3 36 Control Ines ei es ve ie t 3 36 Audio Analog Board A13 esse 3 37 Input Amplifi IS 4 oer E gins Tere aps 3 37 signal Input sese dt eret rU Rete RR T odes 3 37 Stepped Attenuator sese ee E TR TR haar Tere RD re pas 3 37 Input Amplifier eee eH chara ele nie gies ove e e necs 3 37 400 Hz Notch Filter DAC Output lesse eh 3 39 Notch Filter Operation oaa ea a ee het e aee ores 3 39 DA Output ze erre pte one Rhe ala Hh ava ee Re Rs 3 39 Option 40 A D Converter oe aaen EAEAN nnn 3 40 Input Clamp ee ee Rep e e od Siete 3 40 2 and 1 Amplifier 2 e 3 40 A D COBVETIet irse ec ee HERO e rue ER ERR ere Wo Rn 3 40 iv VM700T Video Measurement Set Service Manual Table of Contents Audio Board
13. BD ASSY MOTHER 11 80009 672 1298 01 1 CKT BD ASSY BUS INTERCONNECT A11A1 1 CKT BD ASSY MAIN INTERFACE RIGHT A11A2 1 CKT BD ASSY MAIN INTERFACE LEFT A11A3 47 211 0661 00 6 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 48 Not used 49 Not used 50 Not used 51 Not used 52 337 3658 00 1 SHIELD ELEC RIGHT ALUMINUM 80009 337 3658 00 58 211 0507 00 4 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 54 337 3656 00 1 SHIELD ELEC LEFT ALUMIMUM 80009 337 3656 00 55 211 0507 00 6 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 56 Not used 57 337 3739 00 1 SHIELD ELEC FILTER BOARD 5Y400 337 3739 00 58 211 0101 00 4 SCREW MACHINE 4 40 X 0 25 FLH 100 DEG POZ 93907 ORDER BY DESC 59 361 1590 00 2 SPACER STANDOFF 0 250 DIA X 1 375 L NYLON 05791 NY 6941 0440 1 375 00 60 351 0837 00 2 GUIDE CKT BD 3 935 X 1 35 X 0 55 PLASTIC 0 25 351 0837 00 10 8 VM700T Video Measurement Set Service Manual Replaceable Mechanical Parts Replaceable parts list cont Fig amp index number 61 62 63 64 65 Tektronix Serialno Serial no part number effective discont d 361 1591 00 210 0405 00 211 0001 00 174 3657 00 174 3616 00 671 1787 05 671 1788 05 672 1348 06 671 2337 00 Qty Name amp description pm SPACER STANDOFF 0 250 DIA X 1 375 L NUT PLAIN HEX 2 56 X 0 188 BRS CD PL SCREW MACHINE 2 56 X 0 25 PNH STL CD PL POZ CA ASSY SP RIBBN GENLOCK HDI
14. Clamp and Bias Mode Generator Control To Genlock 4 Ext Board Sync gt Sync Buffer DVM Selecti a Wee To election i Acquisition Control Signals 15 Selection Controller From gt Acquisition Controller Dynamic Offset 4 Dither Generator Generator From Filter gt Switch Board 3 gt 0 Offset Variable Dither Amplifier Gain Amplifier Amplifier a Possible front panel selections using hardware and software A B A B AC B A CX A and C B Possible channel selection combinations in hardware A A B A C B C A B Figure 3 1 Analog input board A1 block diagram 3 4 VM700T Video Measurement Set Service Manual Theory of Operation Differential Amplifier differential amplifier combines the differential output of the switching matrix and produces a single ended video output signal which is connected by coaxial cable to the filter switch board After being filtered if filtering is needed the video signal returns to the analog input board for offset gain and dither processing An acquisition description supplied by application software causes the acquisi tion controller board to dynamically apply dynamic offset programmable variable gain and dither to the input video Dynamic Offset Generator Data bits from the acquisition controller board drive the dynamic offset generator and Offset Amplifier and provide a dynamic offset range of 1 28 to 1
15. Processor Address Buffers VM700 Main A0 31 Processor BR Access Control amp Timing GPIB Connecto ID0 15 gt Control 3 7 Signals Clocks 1 23 IDTACK IBERR Decoding Timing and IA1 23 DPRDO 31 GPIB Processor Dual Port Memory Interface IA1 23 BA0 25 DPRA2 21 Dual Port Memory Controller DPRDO 31 Dual Port Memory MRAO 9 IR W Watchdog Timer 100 15 DPRDO 31 DPRA2 21 Inter processor Communication Register SYS RESET 100 15 J10 GPIB Interface r IA1 23 GPIB Status Indicators IA1 23 100 15 System Clock Tick Debug RS 232 and Forced Inst Buffers Figure 3 18 Block diagram of the GPIB interface option board VM700T Video Measurement Set Service Manual IA1 23 Reset and Halt Generation and General Control Register 3 45 Theory of Operation 3 46 The GPIB processor has no memory cache so it gets its program instructions from the program RAM space Most of the remaining access time the GPIB processor is doing reads and writes to and from the shared and private RAM space It is important that the VM700T processor not be blocked from accessing the shared space so it may communicate with the GP
16. c Adjust R555 to flatten the response ripple and C922 to control peaking and rolloff of the response curve d Ifthe best result is rolled off adjust R186 to bring the response curve up If the response curve is peaked adjust R186 to roll it off Note that the response is specified only to 8 MEZ so it is permissible to have peaking or roll off above 8 MHz to produce a flatter response curve from 0 to 8 MHz 12 Store a reference waveform of the channel A frequency response On the example Gain Phase Analyzer press Display Superimpose Store and Recall A 13 Select 1 select Input Source and select B on the VM700T for channel B input 14 Move the cable and terminator to the channel B feedthrough connectors on the rear panel of the VM700T 15 Check that the channel B response curve matches the stored channel A response curve within specification If the response curve for channel B does not match the stored channel A trace adjust R304 and R138 if necessary to match the the stored trace VM700T Video Measurement Set Service Manual 5 17 Adjustment Procedure 16 Select C on the VM700T for channel C input 17 Move the cable and terminator from the channel B connectors to the channel C connectors 18 Check that the channel C response curve matches the stored channel A response curve within specification If the response curve for channel C does not match the stored channel A trace adjust R276 and R146 if neces
17. 2 12 Keypad The keypad shown in Figure 2 9 contains three five button rows plus an additional five buttons associated with the control knob VM700T MEASUREMENT SET turbo Waveform Vector Picture Measure Auto SOURCE Bi Freeze A B C Average Menu Help Configure Function Copy Select Line Move d 5 Display Graticule Intensity Figure 2 9 Measurement set keypad Manual and Auto Operational Modes The top row of buttons selects the major functions operating modes of the measurement set The measurement set has five operational modes four manual modes and an automatic mode and it operates in one of these modes whenever it is on The manual modes are Waveform Vector Picture and Measure the automatic mode is Auto The power on default mode is Waveform The manual modes perform the specified operation and provide a graphic display with digital readouts and status information Auto mode makes measurements automatically and provides a tabular listing of the measurement results You can get measurement results reported in either mode Parameters such as clamping sync source and the displayed line system line are common for all the manual modes of operation VM700T Video Measurement Set Service Manual Operating Information NOTE Manual mode parameters do not carry over to Auto mode You must set parameters for both the Auto mode and the
18. 6 99 Troubleshooting Option 1S SDI 6 100 SDI Option Diagnostics skr Er a aie Er t HIE RERS 6 104 Standard Options Option 01 and Option 11 7 1 Application Options Option 1G Option 20 Option 21 Option 30 Option 42 7 1 Audio Options Option 40 and Option 41 7 3 Serial Digital Interface Option 15 7 4 GPIB Interface Option 48 7 4 White Phosphor CRT Option 74 7 4 Cabinet and Mounting Options Option VM7FR1 VM7FC1 7 5 Auxiliary Software Options VMBKUP VMT VMREMGR 7 5 Optional Accessories ios esa choke ERS Ae VERE PIRE PERS 7 5 Power Cord Options v os SM e pU 7 6 Parts Block Diagram depo 9 1 Interconnection Diagram en 9 1 Parts Ordering Information stera cir nen 10 1 Using the Replaceable Mechanical Parts List 10 1 VM700T Video Measurement Set Service Manual Table of Contents List of Figures Figure 2 1 Figure 2 2 Figure 2 3 Figure 2 4 Figure 2 5 Figure 2 6 Figure 2 7 Figure 2 8 Figure 2 9 Figure 2 10 Figure 2 11 Figure 2 12 Figure 2 13 Figure 2 14 Figure 2 15 Figure 2 16 Figure 2 17 Power line conditioner with a rackm
19. CA ASSY SP ELEC AQ CONTROLLER 34 32 AWG 2 6 L RIBBON CA ASSY SP ELECTRICAL AMPLIFIER DC 10 28AW G 050 RND L 17 50 2 X 5 FEMALE RCPT 0 10 X 0 1 CA ASSY RF RFD CRIMP 1 75 OHM L 7 50 SMB BOTH ENDS AMP 414002 1 15 CA ASSY RF COAXIAL RFD 1 750HM RG179 7 25 L CA ASSY RF DISCRETE SER VID OUT RFD CRIMP 1 75 OHM L 9 50 STRAP TIEDOWN E 0 098 W X 4 0 L ZYTEL CKT BD ASSY INPUT amp BNC 671 4237 00 PLATE ADAPTER ALUMINUM TV GRAY SCR ASSEM WSHR 4 40 X 0 312 PNH STL CDPL T 10 TORX DR PANEL REAR AL 1S SAFETY CONTROLLED FUSE SMD 7A 125V FAST BLO 0 1X0 1X0 24 UL CSA FUSE THRM CHIP SELF RESETTING FUSE 1 25A HOLD 2 5A TRIP AT 20 DWG C 15V MAX VM700T Video Measurement Set Service Manual Mfr code 80009 80009 80009 80009 80009 23633 060D9 060D9 060D9 060D9 06383 80009 80009 0KB01 TK1943 75915 06090 Mfr part number 671 4136 00 671 4136 01 671 4136 02 671 4136 03 671 4136 04 174 3779 00 174 3850 00 174 3848 00 174 3891 00 174 3849 00 PLT1M 672 1504 00 386 4247 00 211 0409 00 333 4247 00 451007 SMD125 2 10 13 Replaceable Mechanical Parts Replaceable parts list Fig amp index Tektronix Serial no Serial no number part number effective discontd Name amp description Mfr code Mfr part number 10 6 1 159 5014 00 FUSE 2 0A 125V FAST BLOW 0 1 X 0 1 X 0 24 UL CSA 75915 R451 002 6 2 159 5014 00 FUSE 2 0A 125V FAST BLOW 0 1 X 0 1 X 0 24 UL CSA 75915 R451 002 6 3 1
20. FAX 781 665 0780 TestEquipmentDepot com Maintenance Mounting the Rack Slides 6 46 Locate the proper holes in the rack rails as shown in Figure 6 28 Notice that the hole spacing varies with the type of rack When installing the slides in EIA type racks make certain that the slides are attached to the 1 Zinch spaced holes Install the stationary section of the rack slides as shown in Figure 6 29 Make sure the stationary sections are horizontally aligned level and parallel MIL STD 189 spacing O O Y 0 500 1 250 Y Universal spacing Nl O O A Mount the 0 500 A stationary section i to these holes 0 625 0 625 Figure 6 28 Rail detail for mounting rack slides VM700T Video Measurement Set Service Manual Maintenance Front rack rail Front rail mount Barnut Use if front rack rail is not tapped 10 32 PHS screws Rear rack rail 10 32 PHS Screws N E Deep rack mount 10 32 PHS Screws Bar nut Co 10 32 PHS screws eo ES Shallow rack mount p 10 32 PHS Screws Bar nut r Rear rack rail Bar nut Figure 6 29 Mounting stationary rack sections VM700T Video Measurement Set Service Manual 6 47 Maintenance Installation Removal from Figure 6 30 shows how to install and remove the instrument from the rack the Rack Rack Adjustment
21. SLOT 4 Y Y FILTER lt lt Al o FILTER SLOT ASSIGNMENTS 7 SS E RR 7 r q 1 NTSC BW LIMIT SLOT 5 2 IEEE LOW PASS 3 CHROMA BANDPASS 4 DIFF STEP FILTER lt lt 5 LF NOISE Wee AUN ee i J Figure 3 4 Filter switch board A4 block diagram VM700T Video Measurement Set Service Manual 3 15 Theory of Operation CPU Board A5 System Bus The CPU and CPU I O boards are the complete central processing core for the VM700T The CPU board incorporates Flash EPROM program memory nonvolatile memory for data and user programmed routines the front panel interface and the display driver hardware The CPU I O board provides the interface between two RS232 serial ports one parallel printer port and the central processor The CPU board microprocessor runs at 40 MHz A floating point unit FPU processes floating point instructions The microprocessor and the FPU sit on a CPU bus that includes the 32 data lines 32 address lines and control lines from the microprocessor All other buses on the CPU board are 8 bits wide Figure 3 5 is a simplified block diagram of the CPU board showing the major functional blocks of the circuit board MC68331 MC68030 Data Loop CPLD Back Port RS232 Interface SYSTEM BUS DRAM 2M x 32 NVRAM MC68882 ii 256K x 32 EPROM 128K x 16 Address Loop Back Port Prog Reg
22. b Remove the CRT bezel refer to CRT Bezel on page 6 32 Remove the right side card cage retainer refer to step 1 on page 6 16 Disconnect the interconnection cable at J9 on the CPU board Remove the flat head screws holding the Keypad board assembly bracket to the VM700T front frame see Figure 6 21 Carefully separate the Keypad board assembly from the instrument For instruments with serial numbers B050100 and above disconnect the Touch Panel cable from the Controller board and disconnect the three wire RS232 cable from the Controller board For instruments with serial numbers below B050100 do the following instead On the back of VM700T Video Measurement Set Service Manual Maintenance the Keypad board assembly remove the touch panel connector at J933 and the ground wire attached to the standoff to remove the Keypad board assembly Figure 6 21 Removing the retaining screws from the Keypad board 2 Replace the Keypad board assembly by performing step 1 in reverse order reinstall connector J933 on the Keypad board assembly Be sure to orient the connector with its key facing the center of the board see Figure 6 22 Any other connector orientation is incorrect and can cause component failure when the instrument powers on CAUTION For instruments with serial numbers below B050100 you must VM700T Video Measurement Set Service Manual 6 35 Maintenance 6 36 Ground
23. high frequency terminator NOTE If you are using the Tektronix SG 5030 connect the 50 2 75 Q converter between the Output Head and the SDI Ch A input no cable between the Output Head and the input 2 Press the VM700T front panel Measure button and then touch the SDI Eye Diagram soft key 3 Press the VM700T front panel Menu button Touch the Waveform soft key and then select Free Run on soft key is highlighted 4 Press the VM700T front panel Menu button and then touch the Cursors Units softkey 5 Touch the Volt Cursor 1 soft key and then use the front panel knob to position the cursor to 400 mV as read in the readout 6 Touch the Volt Cursor 2 soft key and then use the front panel knob to position the cursor to 400 mV as read in the readout 7 Adjust the amplitude of the leveled sine wave so that the displayed waveform amplitude matches the voltage cursors NOTE It may be necessary to expand the waveform to accurately position the voltage cursors You can expand the waveform by touching the waveform and then using the front panel knob to adjust the waveform display If there is a small DC offset adjust for equal error at the two cursors so that waveform amplitude is 800 mV 8 Setthe frequency of the leveled sine wave to 550 MHz without adjusting the signal amplitude 9 Touch the Volt Cursor 1 soft key and then use the front panel knob to position the cursor to the top of the sine wave 10 To
24. 0 2 100 nominal 0 to 50 1 0 to 10 sec 100 msec 100 Hz 0 5 Hz VM700T Video Measurement Set Service Manual 1 21 Specification Table 1 50 Chrominance to Luminance Gain and Delay Measurement Absolute mode accuracy Relative mode accuracy Chrominance to Luminance Gain Ratio 0 to 160 0 1 Table 1 51 Chrominance Frequency Response Measurement Absolute mode accuracy Relative mode accuracy Reference Amplitude 0 to 100 IRE 0 5 Frequency Response 0 to 100 IRE 0 5 Table 1 52 Chrominance Noise Measurement Range Absolute mode accuracy AM Noise 20 dB to 80 dB 1 dB 20 dB to 60 dB PM Noise 20 dB to 70 dB 1 dB 20 dB to 60 dB Table 1 53 Chrominance Non Linearity Measurement Absolute mode accuracy Relative mode accuracy Chrominance Amplitude 0 to 100 0 5 Chrominance Phase 0 to 360 0 2 Chrominance to Luminance Intermodula 50 to 50 0 2 tion Table 1 54 ColorBar Measurement Absolute mode accuracy Relative mode accuracy Luminance Level 0 to 100 IRE 0 5 IRE 0 2 0 to 714 3 mV Chrominance Level excluding gray and 0 to 100 IRE 1 0 of nominal see 0 2 black 0 to 714 3 mV Table 1 55 Chrominance Phase 180 of nominal 0 5 of nominal 0 1 Table 1 55 SMPTE color bar nominal values Color LUM mV Chroma P P mV Phase degrees Yellow 494 6 444 2 167 1 Cyan 400 4 630 1 283 4 1 22 VM700T Video Measurement Set Service Manual Specificati
25. 5 Do Diagnostics start Instrument Q QUICK Skip Diagnostics start Instrument L LOW LEVEL DIAGS LOOP Loop on Low Level Diagnostics D HIGH LEVEL DEBUG Start Instrument in HL Debug Mode A 5 Do EXTRA Diagnostics start Instrument Reprint Q Abort Menu Input your selection Figure 4 2 Instrument run modes menu To check for soft errors possible intermittent operation run DiagsLoop on all the high level diagnostics while you let the measurement set warm for 20 minutes before starting the verification checks To set up for running all the high level diagnostics in a DiagsLoop do the following tasks at the completion of system initialization Enter the Configure Directory shown in Figure 4 3 by pressing the Configure button If you see a Diagnostic Errors file in the Configuration files either use the Delete soft key to erase it if it is not needed or check it for the last error saved and note its time for reference Touch the Diagnostic Selections soft key m Set the Diagnostic Selection file shown in Figure 4 4 to run all diagnostics refer to Selecting High Level Diagnostics for that procedure m Select Measure mode by pressing the Measure hard key VM700T Video Measurement Set Service Manual Performance Verification m Ifthe Diagnostic measurements are not shown touch
26. 672 1299 09 ORDER BY DESC 366 2159 01 333421500 821 12790 024 ORDER BY DESC 821 12790 024 407 4289 00 97 0605 02 X 657 0098 03 657 0099 03 440 3786 01 119 6974 00 ORDER BY DESC ORDER BY DESC ORDER BY DESC NA ORDER BY DESC ORDER BY DESC 8090 632 24 671 1922 02 10 5 Replaceable Mechanical Parts Replaceable parts list cont Fig amp index Tektronix Serialno Serial no number partnumber effective discontd Qty amp description Mfr code part number 41 441 1814 01 1 CHASSIS CRT 0J260 441 1814 01 42 337 3972 00 1 SHIELD EMI 337 3648 00 337 3660 00 337 3661 00 80009 337 3972 00 ASSEMBLED 43 212 0040 00 7 SCREW MACHINE 8 32 X 0 375 FLH 100 TK0435 ORDER BY DESC DEG STLPOZ 44 337 3660 00 1 SHIELD ELEC 7 46 L BE CU CLIP ON TOP 30817 97 0605 02 X 45 337 3661 00 1 SHIELD ELEC 6 46 L BE CU CLIP ON LEFT 30817 97 0605 02 X 46 174 0844 01 1 CA ASSY SP ELEC 8 22 AWG 16 18 L RIBBON 9M860 174 0844 01 47 407 3613 00 1 BRACKET CA HSG CABLE HOUSING BRACKET 0J260 ORDER BY DESC 48 211 0661 00 1 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 49 343 0088 00 2 CLAMP CABLE 0 062 DIA PLASTIC 80009 343 0088 00 50 119 4258 04 1 PWR SPLY IN 115 230 47 63 HZ OUT 5V 40 15V 80009 119 4258 04 3A 15V 3A 12V2 5A 5 2V 8A VAR FAN OUT 9 29V 15 51 211 0507 00 6 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 52 210 0409 00 1 NUT PLAIN HEX 8 32 X 0 312 BRS CD PL
27. Adjust the digital television signal generator for a jitter frequency of 5 MHz and a jitter amplitude of 1 ns on the signal output b Press the VM700T front panel Menu button c Touch the Rescale soft key and then touch the Cursors Units soft key d Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 5 MHz as read in the readout e Check that the Spectrum Cursor 1 amplitude readout is 8 4 to 14 4 dB f Check that the Timing p p readout is 700 to 1800 ps g Check that the Alignment p p readout is 700 to 1800 ps 6 Perform the following steps to check the Jitter application at 270 Mb and 9 9 MHz a Adjust the digital television signal generator for a jitter frequency of 9 9 MHz and a jitter amplitude of 1 ns on the signal output Press the VM700T front panel Menu button Touch the Cursors Units soft key Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 9 9 MHz as read in the readout Check that the Spectrum Cursor 1 amplitude readout is 8 4 to 17 4 dB Check that the Timing p p readout is 700 to 1800 ps Check that the Alignment p p readout is 700 to 1800 ps VM700T Video Measurement Set Service Manual SDI Option 1S Verification Procedure 7 Perform the following steps to check the Jitter application at 143 Mb and 3 MHz a e f Replace the 270 Mb signal on the SDI Ch A input with a 143 Mb 525 line N
28. After the acquisition has been performed the data is checked to ensure that all 8 bits are moving If so the test passes Otherwise a message is generated to the console for each bit that is stuck low or high Acquired data consists of a 10 bit data sample and 4 flag bits captured synchronously Each of these flag bits can be fed by a variety of sources such as line and frame sync pulses from either channel eye rise fall flags etc This multiplexing is performed by four muxes that are implemented in a PLD U35 Several of these bits are available as inputs to more than one of these 4 muxes The supermux tests exploit this redundancy For each supermux test we set up the mux selector to route the same bit to as many of the flag bits as possible and then we examine the flag bits in the acquired data to verify that the same state is acquired in all the flag bits Even though this description is grouped under one paragraph the tests themselves had to be broken out into separate groups because the diagnostic framework has a time limit for the completion of each test These groups and the bits checked within each are as follows Checks frame sync A and B on Flags 3 2 1 and 0 Checks line sync A and B on Flags 3 2 1 and 0 Checks horiz vert blanking bits on Flags 3 2 1 and 0 Checks the eye rise flag on Flags 3 and 2 VM700T Video Measurement Set Service Manual Options This section provides a brief summary of the available options
29. Electrostatic Discharge Immunity RF Electromagnetic Field Immunity Electrical Fast Transient Burst Immunity Power Line Surge Immunity Conducted RF Immunity Voltage Dips and Interruptions Immunity Radiated Magnetic Field Immunity Balanced Ports Common Mode Immunity Australia New Zea Complies with EMC provision of Radiocommunications Act per the following standard s land Declaration of Conformity EMC AN NZS 2064 1 2 Industrial Scientific and Medical Equipment 1992 FCC Compliance The instrument complies with the radiated and conducted emissions requirements of FCC Code of Federal Regulation 47 Part 15 Subpart B Class A limits 1 To ensure compliance with the above requirements only high quality shielded interface cable should be attached to this instrument High quality cables have a reliable continuous outer shield braid and foil that has low impedance connections to shielded connector housings at both ends 2 Peak Inrush Current 35 5 A 230 VAC 50 Hz 3 VM700T with Power Line Conditioner accessory used on 230 Vac power mains 1 6 VM700T Video Measurement Set Service Manual Specification Table 1 8 Safety standards Category U S Nationally Recognized Testing Laboratory Listing Canadian Certification European Declaration of Conformity Additional Compliance Description UL3111 1 Standard for Electrical and Electronic Measuring and Testing Equipment CAN CSA C22 2 No 1010 1 Safety Requirem
30. If a valid signal is detected then the output of U62 3 for Ch 1 or U163 3 for Ch 2 is sampled through a 33 ohm resistor R777 or R820 to determine if the deserializer chip the Gennum 9000 has detected HSYNC errors If so this test FAILS and the data path test is not performed flagged N A If there are no HSYNC errors then the data path test is conducted The output of the Gennum 9000 deserializer 062 for Ch 1 U163 for Ch 2 is routed to the data acquisition system and a data acquisition is performed Each of the 10 bits of the data path is checked for movement and a message is generated to the console for each bit that is stuck high or low Note that these data bits after they come out of the Gennum part are multiplexed through U35 CHA data CHB Data input VIDEO MUX output Next this video mux output is multiplexed again through U30 coming out of this device as VIDEO OUT 9 0 This is what drives the TTL ECL drivers U139 U140 U141 and 043 for eventual transmission to the Acquisition Controller board The above three tests are repeated for channel B with the same pass fail criteria and test execution constraints There is only one test in this group The SDI board is configured for an eye diagram acquisition The data muxes are set up to pass Channel C data through to the acquisition board and an eye acquisition is performed The 10 data bits are checked for movement and any bits that are stuck high or low are repor
31. If you do you will need to furnish or fabricate an adapter on the signal generator end To Option 40 audio input connectors Figure 4 6 Option 40 cable connections level accuracy and flatness check 3 Press the Measure hard key select Audio and run the Audio Analyzer measurement 4 Using a known accurate sine wave generator or one verified with an accurate AC voltmeter apply a 120 Hz input to the Audio option at amplitudes gt 20 dBu for example 18 8 2 12 dBu and verify that the level accuracy is 0 1 dB 5 Select at least 6 frequencies and 10 amplitudes over the listed range to test The frequencies and amplitudes you select must be in the ranges listed in Table 4 3 use a signal amplitude level of 70 dBu to test for worst case Table 4 4 shows an example selection of test frequencies and amplitudes Table 4 4 Example test signals for level and flatness test Frequency Amplitudes 30 Hz 10 dBu 21 dBu 40 dBu 49 dBu 100 Hz 51 dBu 55 dBu 59 dBu 1 kHz 61 dBu 65 dBu 70 dBu 5 kHz 12 kHz 20 kHz 6 Set the sine wave generator for each of the frequencies and amplitudes you have selected to test 4 16 VM700T Video Measurement Set Service Manual Audio Option 40 Verification Procedure 7 Ateach frequency check that the measured level is accurate to the limits shown record the level for each frequency 8 Verify that any differe
32. NEMA 5 15P Europe A1 230 V United Kingdom 230 V Australia 230 V North America 230 V Switzerland 230 V 1 European and United Kingdom power cord options A1 and A2 also require the VM700T Power Line Conditioner box for operation in EU countries The power line conditioner prevents harmonic emissions from the VM700T power supply from entering the commercial power mains 7 6 VM700T Video Measurement Set Service Manual EEE ISSUE Ur Replaceable Electrical Parts Individual electrical components are not listed because component level repair is not supported in VM700T Video Measurement Set The electrical modules for this instrument are listed in the Replaceable Mechani cal Parts list VM700T Video Measurement Set Service Manual 8 1 Replaceable Electrical Parts 8 2 VM700T Video Measurement Set Service Manual a Diagrams The block diagram and interconnection diagram are provided to assist in identifying the interaction between modules in troubleshooting to the module level Use the exploded view diagrams in the Replaceable Parts List section to locate the modules installed in the VM700T Block Diagram Each module in the instrument is assigned an assembly number for example A20 The assembly number appears on the block diagram The overall block diagram is at the board level More detailed block diagrams of the modules are shown in the section with the discussion of the module circuit ope
33. The DC level adjustment of the vertical deflection circuit produces an offset that centers the display vertically Vertical linearity of the raster is adjusted with the Vertical Linearity potentiometer VM700T Video Measurement Set Service Manual 3 29 Theory of Operation 3 30 Horizontal Deflection High Voltage 12 Vand 45 V 5v Supply 12V Brightness Focus Horizontal y Deflection 455V 100V Horiz Horiz Position Horiz Sync Horiz Video Amplifier Video In Video Out Contrast Vertical Deflection Vertical V Sync Vertical Vert Position Vert Linearity Vert Hold Vert Size Figure 3 12 Picture Monitor simplified block diagram Blanking Amplifier Blanking between vertical sweeps is produced by the blanking amplifier In the output of the blanking amplifier the BRIGHTNESS adjustment sets the level of CRT beam current between blanking pulses The horizontal deflection circuit provides the drive current to the deflection yoke H Sync is applied a PLL phase locked loop circuit that produces the horizontal deflection signal The frequency of the loop is synchronized to the incoming H Sync signal after setting the correct frequency with the Horiz Sync control The output of the PLL is further amplified to drive the horizontal deflection yoke Width of the display on the CRT is set using the Horizontal Width adju
34. Touchscreen controller B050100 amp above A10 Front panel A5 CPU 21 VGA RS 232C 0 RS 232C Port A20 CPU 1 0 X on Printer VGA Out Figure 9 1 VM700T Video Measurement Set simplified block diagram 9 3 Video Out ChAIn J619 J 550 o g oen en J190 3 ChAOut J719 Display J31A 2 Monitor 2 m Touchscreen Touchscreen n M Filter Switch J970 below B050100 B050100 amp A1 Analog Input above S Luc In J111 J995 Poco cc ChBOut G J510 J922 J418 10 2 Keyboard Ch C In G 4310 J915 Touchscreen J148 12V J540 controller B050100 amp Ch C Out 0410 above Video Out Ext Sync In uo J923 45V 10 J159 Video Out J933 Ext Sync Out J110 ji J132 7 Front Panel P659 A21 10 VGA A23 J1 SDI Option A18 J2 VGA OUT S7 Interface ro Acquisition SDI Ch A 3 Green iei fos Ji A COMO er s wl IH J7 J9 J5 A20 p J2 J6 COMI SDI Output Yellow j10 A5 CPU J6 Prin
35. frequency reference Do this procedure for NTSC and PAL TV signals if the VM700T is a dual standard instrument NOTE If the VM700T meets the limits described skip step 17 Adjusting the VM700T unnecessarily for example to get a better reading on a calibration result that is within limits can introduce errors into a functional instrument 17 If adjustment is needed slide the top cover back enough to expose the Genlock board and quickly adjust R138 TCXO REFERENCE on the Genlock board to set the Burst Frequency measurement to zero Slide the top cover back on the VM700T After 5 minutes check the Burst Frequency measurement again to verify that it remains within tolerance NOTE If you performed this procedure after getting out of limit results from Measuring the Burst Frequency in the Performance Verification procedure return to finish the verification steps now This procedure is used to adjust the frequency response flatness over the operating range of VM700T after a board exchange repair or after it is determined that the flatness is out of tolerance by doing the Measure Sinewave check procedure Test Equipment Required Leveled sine wave generator 75 Q output impedance output flat within 0 025 dB 20 3926 to 6 MHz Example HP 3336C with option 005 m Termination 75 Q precision Tektronix part number 011 0102 01 or equivalent Coaxial cable 75 high quality noise free 1 meter length Tektron
36. highlight the and press Select Line button This also returns to the next higher level menu where the choice to run the tests in the custom list you have just made is available When you run the tests all the selected major test headings and the test results are shown along with the sub test that run as part of the diagnostics You can use the other added choice of editing the current test list if you want to make a change in the custom test list without rebuilding the entire list NOTE The custom list you build is not retained when exiting this menu VM700T Video Measurement Set Service Manual 6 63 Troubleshooting Procedures 6 64 Diagnostic Help Menu One of the menu choices in the VM700T START UP MENU is the diagnostic help menu The help menu has two choices List special instrument power up modes and List diagnostic front panel button uses Figure 6 38 lists the front panel buttons that can be used directly to make menu selections These keystrokes are in lieu of highlighting the menu choice and pressing the Select button when one of the listed key choices is available in a menu Low Level Diagnostic Interface DIAGNOSTIC FRONT PANEL BUTTON USES Some Front Panel buttons may be used in place of moving the hilight cursor and pressing the Select button Below are some common diagnostic menu selections and their Front Panel button equivalents Key FR PNL BUTTON SPC Pause Freeze RET Contin
37. is converted to a frequency output and sent to the acquisition controller board where it is averaged by a counter The counter output is read by applications that furnish the APL readout on the display Fifteen other inputs to the DVM selection block are selected by two multi plexers The following selections are included m Outputs of the clamped amplifiers m Offset amplifier m Dither amplifier m Calibration DAC m Video from the filter switch board Analog ground m Clamp levels for channels A B and C TEMPSENSE from a thermistor m REF output from the precision voltage reference VM700T Video Measurement Set Service Manual Theory of Operation The Genlock Board A2 The genlock board sends a constant frequency sampling strobe to the analog to digital converter ADC board The NTSC and PAL television standards are supported by both the genlock board and application firmware A block diagram of the genlock board is shown in Figure 3 2 The sampling strobe may be generated by one of the following three methods or modes The strobe may be phase locked to the incoming video signal synchronous sampling mode to force 910 NTSC or 1135 PAL samples per line The strobe may be phase locked to an internal crystal oscillator running at 20 25 MHz asynchronous sampling mode This method of generating the sampling strobe avoids errors that could be caused by unstable signals typically found in video cassette recorde
38. m Analog board frequency response flat within 30 mdB to 8 MHz when checked with setup described System frequency response flat within 30 to 6 MHz when checked with setup described VM700T Video Measurement Set Service Manual 5 15 Adjustment Procedure Check the Frequency Response 1 Remove the VM700T top cover to access the adjustments 2 Set the controls on the gain phase analyzer as needed For the example gain phase analyzer the controls are set as shown in the gain phase analyzer setup chart shown in Table 5 2 3 Disconnect the cable connecting the Analog Input board to the ADC board J550 to J765 and remove it from the VM700T Table 5 2 Gain phase analyzer setup Control Setting A max 200 mdB Aldiv 30 mdB Function GainPhase Sweep Log Osc Level 300 mVolts Start Freq 100 kHz Stop Freq 20 MHz Marker 8 MHz Output Dual Input Ref 75 Q 0 dB Input Test 1 Meg 20 dB 4 Connect an SMB to BNC adapter to a 75 Q BNC cable attach a 75 2 feed through termination and connect it to the test channel input connector of the gain phase analyzer 5 Connect a second SMB to BNC adapter to a 75 2 BNC cable and connect the BNC end of the second cable to the dual output connector of the gain phase analyzer 6 Connect the two cable adapters on the ends of the BNC cables together using the cable removed from between the Analog Input and ADC boards Normalize the cables and the gain phase analyzer to remove the cab
39. within the limits specified further adjustment is not necessary and is not recommended Adjusting the measurement set unnecessarily for example to get a better reading on a calibration result that is within limits can introduce errors into a functional instrument NOTE This equipment requires a 20 minute warm up period before starting the verification procedures The measurement set must be powered on for at least 20 minutes Measure Squarewave This procedure checks the amplitude accuracy of the instrument An externally applied precision reference signal is used to check the complete signal path through the measurement set Test Equipment Required m Video amplitude calibration fixture VAC Tektronix 067 0916 00 Coaxial cable 75 high quality noise free 1 meter length Tektronix 012 0074 00 Procedure Measure Squarewave 1 Connect the VAC to channel A of the measurement set leave the input unterminated 2 Set the controls of the VAC for NTSC LUM and 700 0 mV 3 On the measurement set press the Measure key the Diags soft key if not already in Diagnostics mode and the Measure Squarewave soft key 4 Check the measurement set for a reading of 700 mV 2 1 mV NOTE If the voltage measured in step 4 is out of the specified limits go to Adjust the Calibration DAC on page 5 9 in the Adjustment Procedure section 5 Move the test signal and select the appropriate channel to repeat the check
40. 0 dB 60 dB to 70 dB Luminance Weighted 20 dB to 80 dB 1 0 dB 20 dB to 60 dB Signal to Noise 2 0 dB 60 dB to 70 dB MHz Low Pass and Unified Weighting Chrominance Weighted 20 dB to 80 dB 1 0 dB 20 dB to 60 dB Signal to Noise 2 0 dB 60 dB to 70 dB Table 1 34 SCH Phase Measurement Absolute mode accuracy SCH Phase 5 Sync Relative Timing 10 ns Burst Relative Phase 5 Table 1 35 Two Field Measurement Range Absolute mode accuracy Field Time Distortion 0 to 35 0 5 Table 1 36 Vertical Blanking Measurement Absolute mode accuracy Equalizing Pulse Width 10 ns Broad Pulse Width 10 ns Vertical Blanking Field 1 NA Vertical Blanking Field 2 NA 1 16 VM700T Video Measurement Set Service Manual Specification Table 1 37 VITS ID Performance Measurement Requirement Supplemental information VITS Recognition Recognizes and displays the name of recognized signals in the vertical interval of both Field 1 and Field 2 lines 15 through 20 VITS test signals recognized are GCR 8 Fields Seq VIRS FCC Multi Burst Pedestal Luminance Bar NTC 7 Combination Sin X X Auto Mode Table 1 38 Line Blanking timing measurements Measurement Range Accuracy Colour Burst Duration 6 cycles to 13 cycles 10 cycles nominal 0 1 cycle Front Porch Duration 0 5 us to 3 us 1 5 us nominal 20 ns Line Blanking 9 us to 16 us 12 us nominal 50 ns Line Sync Rise Time 120 ns to 300 ns 15 ns
41. 128K x 8 Shared RAM NVRAM CPLDS 32K x 8 Status Reg Address Buffer Real Time Clock 20 u Sec Timer Reset Clock Block Flash EPROM 2M x 32 Data Buffer Video Display DIP Switch Block Serial ID Port VGA Display Output Monitor Figure 3 5 CPU board block diagram A buffer connects all 32 data and address lines and the appropriate control lines from the CPU bus to the system bus VM700T Video Measurement Set Service Manual Theory of Operation EPROM EPROM is a 16 bit wide device with a maximum allowed memory of 512 Kbytes This is a read only memory where the system boot up code resides Under normal operation after the boot sequence is complete the CPU executes instructions contained in Flash ROM programmable read only memory NVRAM A 128k x 8 volatile static RAM module with battery backup is used as the nonvolatile random access memory device User programmed routines front panel setups and measurement results are stored in the NVRAM The memory interface allows byte access only The memory defaults to read only at power on or after a system reset NVRAM SIMM The NVRAM consists of two banks of 512 kilobytes SIMM of 32 bits width It is a low power static memory The memory interface allows byte word and long word access The memory defaults to read only at power up or after a system reset The memory interface supports 1 2 and 4 MB SIMM parts Flash EPROM p
42. 1S performance verification procedures 3 Touch the Configure Files soft key and then touch the Source Selection Digital soft key 4 Highlight the Digital A line using the front panel knob and then touch the highlighted line to cause a box to appear around the current selection 5 Turn the knob to select Auto Detect and then touch the Accept Input soft key 6 Highlight the Digital B line using the knob and then touch the highlighted line to cause a box to appear around the current selection 7 Turn the knob to select Auto Detect touch the Accept Input soft key and then touch the Update amp Exit soft key to exit the configuration file NOTE The VM700T and Option 1S must be warmed up for at least 20 minutes before you perform the Option 1S performance verification procedures 4 26 VM700T Video Measurement Set Service Manual SDI Option 1S Verification Procedure SDI Analog Ref Input The amplitude range specification for the SDI Analog Ref input is 6 dB with respect to 1 Vp video Perform the following procedure to check the amplitude range of the SDI Analog Ref input 1 Connect an NTSC black burst signal to the Option 1S Analog Ref input Terminate the signal using two 75 2 feedthrough terminators in series with one 50 feedthrough terminator provides a 0 5 signal Connect a 270 Mb 525 line 10046 color bars signal to the Option 1S SDI Ch A input Terminate the SDI Ch A input using
43. 2 12 The mini XLR ends of these cables connect the Audio option input to an appropriate audio signal source E a Sy Female XLR to male mini XLR adapter cable Figure 2 12 Cables and connectors supplied with Audio Option 40 See Figure 2 13 for the pin assignments for the Option 40 mini XLR connectors You access these connectors at the measurement set rear panel LEFT wer Figure 2 13 Option 40 connectors and pin assignments VM700T Video Measurement Set Service Manual 2 19 Operating Information Connecting Audio Option 41 to a Source The measurement set with Option 41 includes a 37 pin connector located on the back panel Pin assignments for the connector are listed in Table 2 1 Table 2 1 Audio Option 41 connector pin assignments 1 Right 20 2 left 6 2 Right 23 3 Left 9 3 Right 26 For single ended input connect single ended inputs to a Signal pin connect a Signal pin to shield Option 41 Audio Signal Tektronix supplies a DB 37 mating connector kit with Option 41 to assemble the Interconnection Cable signal interconnection cabling The connector pin locations are shown in Figure 2 14 Refer to Option 41 Connector Installation on page 6 12 for complete installation instructions for the connector Input3 X Input2 Input 1 right right right Se LE Male DB 37 v v v Input 3 Inpu
44. 5 V regulators provide a balanced low noise power source for the A D converter The 2 5 V source is the output of a 5 V 3 terminal regulator stacked on the 2 5 V supply The 2 5 V supply has a feedback circuit from the A D converter VREF output The feedback circuit adjust the 2 5 V output over a 0 5 V range to hold the VREF output at ground reference The signal conditioning amplifier is a buffer between the anti aliasing filter and the A D Converter The operational amplifier has 75 input impedance adjustable gain and adjustable response It has low distortion with 150 2 output loading and operates between the 5 V and 5 2 V supplies Its low impedance output directly drives the A D Converter An RC compensation network corrects for the small rolloff of the anti aliasing filter at 5 MHz The amplifier includes a limiter that restricts the output voltage to be between 1 V and 1 V to protect the A D converter input from excessive signal levels or power up transients The A D converter is a 12 bit monolithic converter that operates from 14 mega samples per sec to 20 25 megasamples per second It has a dynamic voltage input range of 0 5 V centered around its VREF output The VREF output is held at ground reference by the feedback to the 2 5 V power source so the input voltage range is centered around ground The architecture of the A D converter delays the output by 3 clock cycles The differential clock input of the converter
45. 53 210 0458 00 1 NUT PL ASSEM WA 8 32 X 0 344 STL CD PL 54 212 0189 00 1 SCR ASSEM WSHR 8 32 X 0 500 PNH STL 0KB01 ORDER BY DESC CDPL T 20 TORX DR MACHINE 54 134 0245 00 1 PLUG BTN 0 156 THK X 0 375 DIA BLACK NYLON 28520 3059 55 337 3653 00 1 SHIELD ELEC CABLE 5Y400 ORDER BY DESC 56 211 0661 00 6 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 57 407 4290 00 1 BRACKET ELEC 407 3780 01 333 3532 00 337 366 80009 407 4290 00 9 00 337 3670 00 ASSEMBLED 58 211 0504 00 5 SCREW MACHINE 6 32 X 0 250 PNH STL POZ TK0435 ORDER BY DESC 59 337 3670 00 1 SHIELD ELEC CLIP ON CU BE 5 25 L 34641 337 3670 00 60 337 3669 00 1 SHIELD ELEC CLIP ON CU BE 9 0 L 34641 337 3669 00 61 337 3532 00 2 SHIELD ELEC BE CU CLIP ON 1 X 2 80009 337 3532 00 62 348 1583 00 B020100 1 SHLD GSKT ELE FINGER TYPE W MAGNEFIL 30817 0097 0510 02 ADHESIVE 6L X 0 343 BECU BRIGHT FINISH 64 211 0516 00 B030422 1 SCREW MACH 6 32 X 0 875 PNH STL CD PL POZ 93907 ORDER BY DESC 65 119 6934 00 B050100 1 TOUCH SCREEN CONTROLLER ELO 2500S 6957 351077 000 66 407 5001 00 B050100 1 BRACKET TOUCH SCREEN CONTROLLER BD TK1943 ORDER BY DESC 67 211 0504 00 B050100 4 SCREW MACHINE 6 32 X 0 250 PNH STL CD 0KB01 211 0504 00 PL POZ 68 129 1602 00 B050100 4 SPACER POST 0 375 L TK0588 ORDER BY DESC 69 174 4948 00 B050100 1 CA ASSY TOUCH SCREEN CONTROLLER BD 98661 174 4948 00 70 211 0503 00 B050100 4 SCREW MACHINE 6 32 X 0 188 PNH STL CD 0KB01 211 0503 00 PL POZ 1
46. 6 9 b Slide the retainer carefully to the left until the screw heads clear the slots and then remove the retainer to expose the CPU board for removal 2 Perform the following steps to remove the CPU board a The CPU board occupies the bottom slot of the right side card cage see Figure 6 10 Use the cable ejector tabs on the front panel interconnec tion cable to disconnect that cable from the CPU board at J9 b Disconnect the multiconductor square pin connectors going to the display monitor 77 and the rear panel connector J6 c Forinstruments with serial numbers B050100 and above disconnect the Touch Panel connector from J5 on the CPU board d Unplug the circuit board using the ejector tab to release the board from the main interconnection board Slide the circuit board out of the card cage ensuring that the standoff on the CPU board clears Ni Loosen screws 2 slide to the left then remove Figure 6 9 Loosening the screws on the right card cage retainer 6 16 VM700T Video Measurement Set Service Manual Maintenance Acquisition C M J7 Display Monitor connector SDI board CPU board 0020 Right side xe Figure 6 10 Location of right card cage circuit boards 3 Perform the following steps to replace the CPU board a Guide the board onto the bottom card cage track and slide it into the card
47. 66 Option 1S simplified block diagram 1 Connect signals to all of the Option 1S rear panel connectors as shown in Figure 6 67 NOTE The internal power up diagnostics for Option 1S provide the greatest degree of testing for instrument functionality when all rear panel connectors have proper signals connected to them When these signals are not present the diagnostic tests that require input signals will report N A not applicable 2 Press the front panel Measure button and then touch the Diag soft key TG2000 DVG1 270 Mb 525 line or 625 line color bars signal TG2000 AVG1 Terminator NTSC or PAL 75 Q black burst signal AM70 48 kHz sampling professional or consumer format SDI Output 1 kHz tone at full amplitude 0 dB 750 Cable connection LTC generator any LTC signal at normal rate Time Code Figure 6 67 Signal connections for performing Option 1S diagnostic tests VM700T Video Measurement Set Service Manual 6 105 Troubleshooting Procedures 6 106 3 Rotate the front panel knob until you locate the SDI Diagnostic soft key 4 Touch the SDI Diagnostic soft key to access the SDI diagnostic routine 5 Touch the appropriate soft key to select the diagnostics run mode type Power Up or Interactive NOTE Diagnostics performed from the Measure menu offer two modes Power Up and Interactive In Power Up mode the diagnostics display a one line header for each test
48. 8 this test is labeled N A and skipped Otherwise the loopback mode is used to route output data from the DAC into the audio data register This test writes long walking 1 and walking 0 sequences to verify each audio data register bit Checks interrupt register bits Tests the run bit to see if it stops and starts code on the DSP Reads the revision bits and checks for range Readable and writeable bits are tested with walking 1 and walking 0 sequences but bits that are read only are tested for resistance to writing Ignored bits are checked to always read 0 If the audio hardware revision number is less than 8 this test is labeled N A and skipped Otherwise the loopback mode is used to route output data from the DAC into the audio data register The DAC generates long sequences of known values toggling at known intervals These are sampled by the audio data register into DSP shared memory and analyzed by the CPU microprocessor VM700T Video Measurement Set Service Manual 6 97 Troubleshooting Procedures NOTE The Audio Analog board tests require an operating Audio Processor board A12 because they involve synchronized exchanges between a DSP program running on the audio processor microprocessor and an application running on the CPU microprocessor Table 6 12 Audio Analog board diagnostics Test name DAC calibration offset and gain ADC calibration offset and gain ADC bit patterns Cal signal paths Attenuat
49. 80009 671 4108 00 671 4108 01 B020231 B031021 1 CKT BD ASSY ACQUISITION MEMORY A18 80009 671 4108 01 671 4108 02 B031022 1 CKT BD ASSY ACQUISITION MEMORY 18 80009 671 4108 02 671 4356 00 B030100 B031018 1 CKT BD ASSY ACQUISITION MEM A18 OPT 1S 80009 671 4356 00 671 4356 01 B031019 1 CKT BD ASSY ACQUISITION MEM A18 OPT 18 80009 671 4356 01 34 Not used 35 671 2470 00 B010100 B010842 1 CKT BD ASSY CPU A5 80009 671 2470 00 671 2470 01 B010843 B029999 1 CKT BD ASSY CPU A5 80009 671 2470 01 671 2470 02 B030100 B030566 1 CKT BD ASSY CPU A5 80009 671 2470 02 671 2470 03 B030567 1 CKT BD ASSY CPU A5 80009 671 2470 03 36 343 1328 00 1 RTNR CKT BOARD LEFT 5Y400 ORDER BY DESC 37 213 0919 00 1 THUMBSCREW 6 32 0 312 X 0 25 OD SST 0KB01 213 0919 00 38 354 0163 00 1 RING RETAINING TYPE E EXT U O 0 125 ID SFT 79136 5133 12ZD 39 348 0102 00 1 PAD CUSHIONING 13 76 X 0 67 X 0 188 RUBBER 2K262 ORDER BY DESC 40 386 6667 00 2 PANEL BLANK 80009 386 6667 00 41 211 0661 00 3 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 42 671 2799 00 B010100 B029999 1 BD ASSY I O A20 80009 671 2799 00 671 2799 01 B030100 1 BD ASSY I O A20 80009 671 2799 01 48 211 0661 00 1 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 44 386 6662 00 1 PANEL CKT BD DOUBLE BLANK W OUT 40 80009 386 6662 00 OPT 41 45 Not used 46 672 1298 00 05 07 2001 1 CKT BD ASSY MOTHER 11 80009 672 1298 00 672 1298 01 05 07 2001 1
50. Alarm Logic circuitry also drives the Over Temp LED and PS Fail LED front panel indicators as feedback to the user of the existing problem Fan Drive separate Fan Drive circuit provides a temperature related drive voltage to the fan As the temperature rises the fan is driven faster to compensate for the rise The temperature sensing element for the voltage control is mounted on the 5 V power supply heat sink Option 40 Audio Measurements This section describes the operation of the VM700T Video Measurement Set audio option boards The discussion provides the background information needed for fault isolation to the board level and board replacement it does not include a component level description component level circuit repair is beyond the scope of this manual Audio Processor Board 12 The following paragraphs discuss the Audio processor board Refer to Figure 3 14 as you read the discussion VM700T Video Measurement Set Service Manual 3 33 Theory of Operation 68020 Data Bus Program Memory 16K 64K Words VA gt To Audio Analog Board 24 24 Audio Processor udio Interface ontro From Reset Control Register Register Audio Analo Boar Figure 3 14 Audio Processor block diagram Audio Processor Interface Address Decoders Bus Buffers Address Buffers 3 34 The Audio Processor Interface consists of address decoders bus buffers and address buffers Addres
51. C Diagnostics CONFIGURATION Menu H Diagnostics HELP Menu T Calibrate TOUCH PANEL INTERFACE Input your selection Figure 2 2 VM700T Startup menu 3 Use the large control knob to highlight the T in the Calibrate Touch Panel Interface line of the VM700T startup menu Press the Select Line button to make the selection to calibrate 4 The first touch screen calibration instructions are then displayed as shown in Figure 2 3 Follow the written directions Pressing AUTO aborts the calibration process and returns you to the startup menu Pressing any other button stores the setting in NVRAM and brings up the next touch screen calibration menu VM700T Video Measurement Set Service Manual 2 5 Operating Information 2 6 TOUCH PANEL INTERFACE CAL DISPLAY Use the knob to adjust horizontal position and squareness of the screen border lines Press AUTO button to abort or any other to accept and store current setting Current Setting 14 Figure 2 3 Touch screen calibration display 5 After making the adjustment requested and storing the current setting the VM700T displays a second set of instructions as shown in Figure 2 4 Follow the directions given in the screen TOUCH PANEL INTERFACE CAL PANEL press AUTO to abort TOUCH THE DOT INSIDE THE SQUARE Place finger tip directly over the dot being careful to avoid parallex Keep touching the dot until th
52. DIAGNOSTICS CONFIGURATION MENU Key Selection P Set Diagnostics POWERUP MODE I Set Diagnostics INTENSITIES B Set Low Level Diagnostics Console DEFAULT BAUD RATE Reprint Abort Menu Input your selection Figure 2 6 Diagnostic configuration menu VM700T Video Measurement Set Service Manual 2 7 Operating Information 2 In Diagnostics Configuration menu highlight and select P in the Set Diagnostics Powerup Mode line to bring up the powerup mode choices shown in Figure 2 7 3 Inthe Set Diagnostics Powerup Mode menu either highlight and select O to have the measurement set skip diagnostics on power up or highlight and select P to have the measurement set run diagnostics on power up The other choices in the menu are used in diagnostic testing in manufacturing and factory service Your selection is stored in the diagnostics NVRAM 4 Turn the VM700T off and back on again to restart normal operation Low Level Diagnostic Interface knob moves cursor Select Line inputs selection SET DIAGNOSTICS POWERUP MODE Select a Powerup Mode from the list below The mode selected will be stored in Diag NVRAM and will be effective for NORMAL powerups ie Boot Switches in NORMAL position The current Powerup Mode setting is STARTUP MENU Key Selection Q QUICK START Skip Diagnostics start Instrument M STARTUP MENU ee ee ee eee Goto
53. Diagnostics Selected Line 6 Not Selected Figure 6 54 Power up diagnostics selection display All diagnostic routines on the Selected side execute during Powerup Diagnos tics or Diags Loop To select or unselect a diagnostic from the Diagnostics Selection file do the following steps l Press the Configure button 2 Press the Configure Files soft key 3 Select the Diagnostics Selection file 4 Turn the control knob until the diagnostic s name is highlighted Touching the vertical center of the left half of the screen selects the highlighted diagnostic touching the vertical center of the right half unselects it 5 Press the Update amp Exit soft key to write out save any changes to the file press the No change amp Exit soft key to leave the file as it was when it was last saved High Level Diagnostics Test Figure 6 55 illustrates the diagnostic test blocks of the high level diagnostics to assist you in determining the module interdependen cies for the successful completion of the tests Table 6 4 lists and describes the VM700T high level diagnostic tests Additional diagnostics are added to this list with the addition of the hardware options GPIB Interface Audio Measurements and Serial Digital Interface 1 The AudioProcessor Diagnostic and AudioAnalog Diagnostic selections are available only with the VM700T Audio option GPIB Diagnostics is added to this list when the GPIB option is installed 6 78 VM70
54. Figure 4 1 select R Instrument Run Modes Menu and press the Select Line hard key to display the Run Mode Menu shown in Figure 4 2 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection VM700T STARTUP MENU Key Selection Instrument RUN MODES Menu UTILITIES Menu Low Level DIAGNOSTICS Menu Diagnostics CONFIGURATION Menu Diagnostics HELP Menu Calibrate TOUCH PANEL INTERFACE 4 Reprint Q Abort Menu Input your selection Figure 4 1 VM700T Startup Menu VM700T Video Measurement Set Service Manual 4 1 Performance Verification Checking for Soft Errors 4 2 In the Run Modes Menu select A Auto Reset This restarts the measurement set and runs the full set of internal diagnostics Check that all tests pass as they run If a test fails refer to the appropriate text in the Maintenance section for further actions you can take to determine which board or boards may be at fault Low Level Diagnostic Interface knob moves cursor Select Line inputs selection INSTRUMENT RUN MODES MENU The instrument will be reset to run in the mode selected below overriding current boot switch settings Key Selection N NORMAL POWERUP Start Instrument in Powerup Mode Current Powerup Mode is QUICK START abort this menu and go to the DIAGNOSTICS CONFIGURATION MENU to change it P POWERUP
55. Manual This manual contains the following sections 1 10 Specification lists the major specifications of the VM700T as an instrument Option specifications are contained in the associated Option User Manuals Operating Information introduces the VM700T gives the basic installation instructions describes its major features and the controls and connectors of the instruments Theory of Operation contains functional block descriptions of the VM700T circuit board modules to aid in understanding the instrument for servicing Performance Verification has the procedures for verifying the operation of the VM700T and the audio options Adjustment Procedure has the procedures for returning the VM700T to specification after a circuit board module exchange Maintenance provides the customer service information and illustrated step by step procedures for removing and replacing the field replaceable modules of the VM700T Installation instructions for the rack mounted instrument are in this section Troubleshooting and diagnostic information is provided to help you troubleshoot the VM700T to isolate a faulty circuit board module for a module exchange repair Options has a listing with a short description of the available options for the VM700T Replaceable Electrical Parts List refers you to the Replaceable Mechanical Parts List for the list of replaceable electrical parts Diagrams provides an overall block diagram and a circuit board
56. Mbit component serial digital video signals Continuous real time format analyzer with event logging and frame capture captured frames can be downloaded to a PC Longitudinal Time Code input for time stamping error events m External and embedded digital audio measurements including audio to video timing measurements Conformance testing to SMPTE 259M and SMPTE RP 165 digital error detection and reporting m Ancillary data analysis with data distribution display m Relative to reference mode allowing signal comparisons m Digital video wander measurements GPIB Interface Option 48 This option provides the hardware and firmware to support a GPIB interface for remote control of the VM700T or hard copy output to a GPIB printer White Phosphor CRT Option 74 This option provides a display module with a white phosphor CRT instead of the standard green phosphor when a new instrument is ordered with Option 74 from the factory All the display module adjustments are the same as those for the standard CRT 7 4 VM700T Video Measurement Set Service Manual Options Cabinet and Mounting Options Option 1C VM7FR1 VM7FC1 Cabinet Version This option provides the VM700T in a cabinet version from the factory The Option 1C standard order configuration is rack mounted Rack Mounting Kit This field installable option provides a rack mounting conversion kit for the VM7FR1 VM700T This kit converts a cabinetized measurement set
57. Measurement SCH Phase Sync Relative Timing Burst Relative Phase Table 1 69 Short Time Distortion Measurement Absolute mode accuracy Short Time Distortion 0 to 2596 SD 5 SD Table 1 70 Two Field Measurement Absolute mode accuracy Field Time Distortion 0 to 4096 0 5 VM700T Video Measurement Set Service Manual 1 25 Specification Table 1 71 VITS ID Measurement Performance requirement Supplemental information VITS Recognition Recognizes and displays the name of recognized signals in the vertical interval of both Field 1 and Field 2 lines 15 through 20 VITS test signals recognized are GCR 8 Fields Seq VIRS FCC Multi Burst Pedestal Luminance Bar NTC 7 Combination Sin X X Table 1 72 Vertical Blanking Measurement Equalizing Pulse Width 80 ns to 1 us Serration Pulse Width 80 ns to 1 us Auto Mode Table 1 73 RS 170A horizontal blanking interval timing Measurement Range Accuracy specifications Color Burst Width Horizontal Blanking Front Porch Duration Horizontal Blanking Horizontal Blanking Width Horizontal Blanking Horizontal Sync Rise and Fall Time 80 ns to 120 ns 10 to 30 ns Horizontal Blanking 120 ns to 300 ns 20 ns 300 ns to 1 0 us 30 ns Horizontal Sync Width 1 us to 8 us Horizontal Blanking Sync to Setup 5 usto 18 us Horizontal Blanking Sync to Start of Burst 4 us to 8 us 140 ns Horizontal Blanking 0 5 cycles 20 ns 1 26 VM700T V
58. OD 7 442 L 80009 348 0276 01 26 252 0571 00 1 NEOPRENE EXTR CHAN 0 234 X 0 156 85471 ORDER BY DESC 27 348 0150 00 1 GROMMET PLASTIC DK GRAY U SHAPE 0 66 ID 0 25 NA 28 351 0602 00 10 GUIDE CKT BOARD MAIN CHASSIS POLYAMIDE 80009 351 0602 00 29 351 0752 00 8 GUIDE LIGHT ACRYLIC GRATICULE TK1908 PER TEK DRAWING 30 407 3687 00 1 BRACKET AIR ALUMINUM 80009 407 3687 00 31 211 0507 00 1 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 82 351 0817 00 5 GUIDE CKT BD NYLON 6 0 L 32559 DC 600 33 348 0089 00 3 BUMPER PLASTIC 0 312 DIA X 0 855 L BLCK VINYL 0JRO5 348 0089 00 34 426 2221 06 1 FRAME ASSY 80009 426 2221 06 35 333 4214 00 1 PANEL REAR REAR PANEL 0 062 ALUM TK1943 333421400 36 211 0507 00 6 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 37 671 3976 00 1 VGA CONNECTOR ASSY A21 80009 671 3976 00 38 214 3903 01 2 SCREW JACK 4 40 X 0 312 EXT THD 4 40 INT THD OKBO1 214 3903 01 39 174 3652 00 1 CA ASSY RBN IDC 10 28 AWG 24 0 L 2X5 VGA TK1547 174 3652 00 40 337 4154 00 020100 1 SHLD ELEC SLOTTED SHIELD 8 626LX0 76W TK2647 0097 0952 02 41 407 4585 00 030100 1 BRACKET EMI 0 062 THK RIGHT SIDE FRONT TK1943 407 4585 00 42 119 5870 00 B030100 1 FILTER EMIFAN 0 050 AL 5052 H3X 4 7 X 4 7 30817 119 5870 00 43 212 0189 00 4 SCR ASSEM WSHR 8 32 X 0 500 PNH STL T 20 0KB01 ORDER BY DESC 10 10 VM700T Video Measurement Set Service Manual Replaceable Mechanical Parts Replaceable parts
59. Performance Verification Diagnostic Errors File When high level diagnostics are run any errors detected are written to the Diagnostic Errors file The contents of this file can be printed using the Print File soft key or the file can be deleted using the Delete soft key If diagnostic errors appear refer to the Diagnostics information starting on page 6 55 The maximum capacity for the Diagnostic Errors file is 100 lines If the number of errors detected causes the file to exceed this length the earlier results are scrolled out of the file buffer When this occurs the Diagnostic Errors file includes a message stating that some of the text has been scrolled out of the file VM700T Video Measurement Set Service Manual 4 5 Performance Verification Test Equipment Required The test equipment to use for performing the verification procedures is shown in Table 4 1 Test equipment suggestions for use in doing the verification procedure are given in the example column The examples given are based on the test equipment that many customers and the Tektronix service centers have installed for supporting the VM700 family of video measurement sets Substitute test equipment may be used if available Refer to the Minimum Specification column to determine the key specifications needed to verify the accuracy of the VM700T Video Measurement Set Table 4 1 Test equipment required for verification Test Equipment Minimum Specification Exa
60. Procedures NOTE The VM700T must be set to Mode Digital The Source Selection Digital configuration file must be set Auto Detect or for the bit rate and standard of the digital test signal 3 Check for a Loss of Signal message on the display 4 If hardware trouble is indicated other than the Loss of Signal message replace the SDI board NOTE Various user settings can dramatically alter the displayed waveform in ways that may appear to indicate a malfunctioning circuit In the SDI Waveform application these user settings include Menu selections of Style Display Display Diff Free Run as well as the front panel controls of Move and Expand Verify these settings before assuming a malfunction exists 5 Swap the SDI Ch A and SDI Ch B cable connections on the SDI board at J7 and J8 see Figure 6 65 6 Connect the signal input to the SDI Ch B input connector leave the VM700T front panel set to display the channel A signal 7 Check that there is a signal display 8 Ifthere is still no signal display on channel A replace the SDI board 9 Ifthere is a signal display on channel A 10 Check J5 pin 9 for 13 to 15 VDC see Figure 6 65 11 Check J5 pin 10 for 13 to 15 VDC 12 If one or both voltages are bad replace the SDI board 13 If both voltages are good remove the SDI Rear Panel Interface assembly 14 Check that the cables are properly seated in their connectors on the SDI Rear Panel Interface
61. Pulse and the quadrature output of the demodulator on Channel C Table 1 61 Jitter Measurement Absolute mode accuracy Jitter 2 Field 10 ns Jitter Long Time 10 ns Table 1 62 K Factor Measurement Absolute mode accuracy 2T Pulse K Factor 0 to 10 Kf 0 3 Kpg 10 to 5 Kpg 0 3 Pulse to Bar Ratio 10 to 125 0 7 Pulse Half Amplitude Duration HAD 100 ns to 500 ns 5 ns Table 1 63 Level Meter Measurement Range Absolute mode accuracy Level Meter 0 to 1 4 V 3 5 mV Table 1 64 Line Frequency Absolute mode accuracy 0 1 0 1 Measurement Line Frequency Field Frequency 1 24 VM700T Video Measurement Set Service Manual Specification Table 1 65 Luminance Non Linearity Measurement Absolute mode accuracy Relative mode accuracy Luminance Non Linearity 0 to 10096 0 2 Table 1 66 Multiburst Measurement Absolute mode accuracy Relative mode accuracy Reference Flag or Packet Amplitude 30 IRE to 130 IRE NA Other Packets 0 5 1 25 2 0 3 0 3 58 40 dB to 6 dB 0 1 dB 0 03 dB 4 1 MHz Table 1 67 Noise Spectrum Measurement Absolute mode accuracy Unweighted Signal to Noise Ratio 20 dB to 80 dB 0 4 dB 20 dB to 60 dB MHz Low Pass 1 0 dB 60 dB to 70 dB Weighted Signal to Noise Ratio 20 dB to 80 dB 1 0 dB 20 dB to 60 dB MHz Low Pass and Unified Weighting 2 0 dB 60 dB to 70 dB Table 1 68 SCH Phase
62. SDI Ch A input no cable between the Output Head and the input 2 Press the VM700T front panel Measure button and then touch the SDI Eye Diagram soft key 3 Press the VM700T front panel Menu button 4 Touch the Waveform soft key and then select Free Run on soft key is highlighted 5 Press the VM700T front panel Menu button and then touch the Cursors Units softkey 6 Touch the Volt Cursor 1 soft key and then use the front panel knob to position the cursor to the top of the sine wave NOTE It may be necessary to expand the waveform to accurately position the voltage cursors You can expand the waveform by touching the waveform and then using the front panel knob to adjust the waveform display 7 Touch the Volt Cursor 2 soft key and then use the front panel knob to position the cursor to the bottom of the sine wave 8 Check that the V1 V2 measurement readout is 770 mV to 820 mV 800 mV 3 89 4 28 VM700T Video Measurement Set Service Manual SDI Option 1S Verification Procedure Eye Diagram Frequency The frequency response 20 to 80 rise time specification for the SDI Eye Response Diagram application is 100 ps for rise times between 400 ps and 1 5 ns Perform the following procedure to check the frequency response of the SDI Eye Diagram application 1 Connect a 50 kHz 1 25 Vy leveled sine wave through a 50 2 75 converter to the SDI Ch A input Terminate the SDI Ch A input with a 75
63. Service Manual XV General Safety Summary xvi Symbols and Terms A A Terms in this Manual These terms may appear in this manual WARNING Warning statements identify conditions or practices that could result in injury or loss of life CAUTION Caution statements identify conditions or practices that could result in damage to this product or other property Terms on the Product These terms may appear on the product DANGER indicates an injury hazard immediately accessible as you read the marking WARNING indicates an injury hazard not immediately accessible as you read the marking CAUTION indicates a hazard to property including the product Symbols on the Product The following symbols may appear on the product A AN m WARNING Protective Ground CAUTION Double High Voltage Earth Terminal Refer to Manual Insulated VM700T Video Measurement Set Service Manual SS Service Safety Summary Only qualified personnel should perform service procedures Read this Service Safety Summary and the General Safety Summary before performing any service procedures Do Not Service Alone Do not perform internal service or adjustments of this product unless another person capable of rendering first aid and resuscitation is present Disconnect Power To avoid electric shock disconnect the main power by means of the power cord or if provided the power switch Use Caution When Servici
64. Timing Accuracy 1ms Option 48 GPIB Specification The GPIB interface function set implemented in the VM700T GPIB interface and the capability level is given in Table 1 95 1 36 VM700T Video Measurement Set Service Manual Specification Table 1 95 IEEE 488 1 interface functions implemented in the VM700T GPIB interface card Function Notes Source Handshake SH1 Complete capability Acceptor Handshake AH1 Complete capability Talker Basic Talker Serial Poll Unaddr if MLA Talker extended TEO No capability Listener L4B Basic Listener Unaddr if MTA Listener extended LEO No capability Service Request Complete capability Remote Local No local lock out Parallel Poll No capability Device Clear Complete capability Device Trigger DTO No capability Controller No capability m Electrical Interface Three state bus drivers Table 1 96 GPIB Electrical characteristics Characteristic Performance requirement Comments Output Signal Levels Logical 0 gt 2 0 V IEEE Std 488 1979 3 2 Logical 1 0 8 V Data Transfer Rate Greater than 1 kbyte per second Connectors GPIB Standard GPIB parallel connector VM700T 3 x 50 square pin connector Connects to VM700T inter connection board Power Requirements 5 Power Consumption 35 W maximum Fuse 5 Vin 10 A fast blow Located on the GPIB module VM700T Video Measurement Set Service Manual 1 37 Specification Table 1 97 Mechanica
65. Unplug the board using the ejector tab and remove the board from the card cage 2 Perform the following steps to replace the GPIB Interface board a Guide the board onto the card cage track and slide it into the card cage connector see Figure 6 4 Align the circuit board connector pins with the main interconnection board connector and press firmly to seat the connector Replace the circuit board retaining screw Replace the circuit board center support and screw Replace the carrying handle cover and screws CPU Board Removaland As you face the front of the VM700T in the operating position the CPU board Replacement 5 is located in a card cage on the right side To remove this board you must first remove the right side cover and the card cage retainer You must also disconnect one or more cables from the board The following procedures explain how to remove the CPU board Required Tools Use the following tools to remove the CPU circuit board m Flat blade screwdriver 3 1 or inch blade m Pozidriv screwdriver 1X VM700T Video Measurement Set Service Manual 6 15 Maintenance Procedure Use the following procedure to remove and replace the CPU board 1 Perform the following steps to remove the right side card cage retainer a Remove the right side cover panel refer to Cover Panel Removal and Replacement on page 6 8 Loosen but do not remove two screws on the front of the card cage retainer see Figure
66. VM700T Startup Menu us POWERUP DTAGS eo a eee cee Do Diagnostics start Instrument L LOW LEVEL DIAGS LOOP Loop on Low Level Diagnostics D HIGH LEVEL DEBUG Run Instrument in DEBUG MODE Reprint Q Abort Menu Input your selection Figure 2 7 Set diagnostics power up mode menu Measurement Set Operating Modes 2 8 Waveform Mode The measurement set has multiple operating modes These modes provide different measurements and different means of making measurement The following information explains each of the operating modes For detailed waveform analysis you can display the actual signal and take additional measurements manually In Waveform mode cursors are available to aid in measuring time frequency and amplitude These cursors allow precise location of 10 50 and 90 percent points on any transition VM700T Video Measurement Set Service Manual Operating Information You can expand the waveform display around any vertical or horizontal point Since the data is digitized the display is bright at all expansion factors The axes automatically expand with the waveform so all units are correct as displayed Vector Mode Vector mode provides the normal vectorscope display You can rotate or expand the vectors the rotation angle and gain values are displayed numerically on the screen A unique Find Colorbars feature searches the video signal for color bars an
67. a 75 2 high frequen cy terminator Set the digital television signal generator for a vertical delay of 262 lines on the 10046 color bar signal Press the Source A button to select channel A for display and then press the VM700T front panel Measure button Touch the SDI IC Timing soft key Press the front panel Menu button and then touch the Relative Analog soft key Check the measurement reading VM700T firmware version 980422 and below 16 mSec to 17 VM700T firmware version 990512 and above 16 mSec to 17 mSec Remove the three terminators from the signal on the Analog Ref input Check the measurement reading m VM700T firmware version 980422 and below 16 mSec to 17 m VM700T firmware version 990512 and above 16 mSec to 17 VM700T Video Measurement Set Service Manual 4 27 SDI Option 1S Verification Procedure Eye Diagram Application Perform the following procedures to check the SDI Eye Diagram application Eye Diagram Amplitude amplitude accuracy specification for SDI Eye Diagram application is Accuracy 5 for signals between 600 mV and 1 Perform the following procedure to check the amplitude accuracy of the SDI Eye Diagram application 1 Connect a 67 5 MHz 800 mV leveled sine wave to the SDI Ch A input Terminate the SDI Ch A input with a 50 precision terminator NOTE If you are using the Tektronix SG 5030 connect the Output Head directly to the
68. are 0 dB and the notch filter is off VM700T Video Measurement Set Service Manual Troubleshooting Procedures Troubleshooting Option 48 GPIB Troubleshooting the GPIB board consists of running the GPIB diagnostics The GPIB Diagnostic routine does extensive testing of the interface hardware Failure of any diagnostic test indicates a hardware problem that requires servicing The VM700T may function for local operation but may be faulty for remote operation if a GPIB Diagnostic test fails Refer to Diagnostic Selection File on page 6 78 to configure the Diagnostic Test Selection file to either run or skip the GPIB diagnostic when running the high level diagnostics The main test titles are as follows VM IPC Register VM Program RAM VM Shared RAM VM Private RAM VM Cen Ctl Reg VM Gpib Chip GP Program RAM GP Shared RAM GP Private RAM GP Spurious Ints GP Int From VM GP Clk Tick Int GP Get Int Each of these main tests have a number of subtests Refer to Appendix B of the VM700T GPIB Interface Programmer Manual for the complete test list if you need to further troubleshoot the GPIB board VM700T Video Measurement Set Service Manual 6 99 Troubleshooting Procedures Troubleshooting Option 1S SDI 6 100 No Signal From the SDI Ch A Input The purpose of the troubleshooting techniques described here is to isolate an SDI option fault to one or both of the SDI boards After isolation the faulty board s may be exchanged
69. at J9 replace it now otherwise verify that the cable is seated correctly in the connectors f Replace the carrying handle cover and screws Option 41 Connector VM700T with Option 41 includes 37 pin connector located on the Installation instrument back panel Pin assignments for the connector are listed in Table 6 2 Table 6 2 Audio Option 41 connector pin assignments 1 Left 3 1 Right 20 2 left 6 2 Right 23 3 Left 9 3 Right 26 1 For single ended input connect single ended inputs to a Signal pin connect Signal pin to shield 6 12 VM700T Video Measurement Set Service Manual Maintenance Tektronix supplies a DB 37 mating connector kit for Option 41 users for assembling the signal interconnection cabling The supplied kit provides several sizes of cable adapter collars Select the one fits your cable and put it on the cable before assembling the wiring to the connector as shown in Figure 6 6 See Table 6 2 for the connector pin assignments The connector pin locations are shown in Figure 6 7 The Tektronix part number for the DB 37 connector is 200 3947 00 After assembling the connector and checking out the wiring install the EMI reduction ferrite choke as instructed below Figure 6 6 Orientation of the cable adapter collar Input3 X Input2 Input 1 right right right ENSURE Input 3 Input 2 Input 1 left left left Figure 6 7 Option 41
70. being run Should the diagnostics encounter an error the measurement set waits for user acknowledgement In Interactive Mode the diagnostics display more detail about each test being performed Before starting the next test in the list the measurement set waits for user acknowledgement 6 Observe the displayed diagnostic test results as they are performed Diagnostic tests that do not pass display a highlighted Fail message 7 The Rerun Test soft key lets you rerun diagnostic tests VM700T Video Measurement Set Service Manual Troubleshooting Procedures Option 1S Diagnostics Table 6 13 describes each the SDI diagnostic tests Table 6 13 SDI Option 1S diagnostic test descriptions Test name SDI board version SDI board ID bits Acquisition memory size System size Xcheck SDI serial EEPROM EEPROM initialized EEPROM checksum Description This is a miscellaneous group of tests which verify and or display the particulars of the SDI board and the environment it needs to work properly These tests are as follows There is an 8 bit board ID field encoded on the board The least significant 4 bits of this field are implemented by means of resistors R912 R913 R914 and R915 and can be influenced by installing or not installing these resistors The next 4 bits are encoded with the PAL U730 The first diagnostic in this group simply reads these 8 bits on the least significant 8 bits of the processor s data bus an
71. board J1 on the A18 board VM700T top view J3 on the A22 SDI board Opt 1S only J6 on the A18 board Figure 6 11 Acquisition Memory board A18 cables Option 15 SDI Boards Option 1S hardware consists of an SDI board A22 an SDI Rear Panel Removaland Interface assembly A23 and interconnecting cables As you face the front of Replacement the VM700T in the operating position the SDI board is located in a card cage on the right side To remove this board you must first remove the right side cover and the card cage retainer You must also disconnect five cables from the circuit board Required Tools Use the following tools to remove the Option 1S hardware m Flat blade screwdriver 3 16 or inch blade W Pozidriv screwdriver 1X 2X VM700T Video Measurement Set Service Manual 6 19 Maintenance SDI Board Use the following procedure to remove and replace the Option 1S SDI circuit board l Perform the following steps to remove the SDI board a Remove the right side cover panel refer to Cover Panel Removal and Replacement on page 6 8 Remove the card cage retainer refer to step 1 on page 6 16 The SDI board occupies the second from the top slot in the right side card cage see Figure 6 10 on page 6 17 To remove this board you must first disconnect five cables from the board Disconnect the cables from the SDI board at J8 J7 J10 and J5 see Figure 6 12 Spread the cable ejecto
72. board at 18 Disconnect the wire at J10 Remove the seven board retaining screws and carefully lift the board from the VM700T chassis 2 Perform the following steps to replace the Genlock board a 6 26 Place the Genlock board carefully on its hardware standoffs ensuring that the ribbon cable is positioned with its connector through the slot in the right side of the instrument chassis see Figure 6 16 Install the seven board retaining screws Connect the wire at J10 Connect the flat 10 conductor cable between J111 on the ADC board and J6 VM700T Video Measurement Set Service Manual Maintenance i n Power bus cable Een s on the VM700T top view A18 board J8 on the A2 board uec T Ml J10 2 J6 Jtt Figure 6 16 Removing the Genlock board e Install the power bus cable at its fi
73. cage VM700T Video Measurement Set Service Manual 6 10 Maintenance Option 40 and Option 41 As you face the front of the VM700T in its operating position the Audio Audio Boards Removal Processor A12 and Audio Analog A17 boards are located in the left side card and Replacement cage with the I O board A20 and if installed the GPIB Interface Option A19 board You may use these procedures to remove and replace both boards To remove these boards you must first remove the left side cover panel to gain access Then remove the retainers and screws holding the boards in the card cage If you are removing only one of the boards first remove the flat cable between the boards at connector J9 Otherwise leave the flat cable connected and remove both boards at the same time Figure 6 5 shows where the audio option boards are located in the left side card cage Card cage center support Audio Analog board A13 option 40 000000000000 or A17 option 41 o 0000000000000 A12 Audio Processor board Seco ub DD BO gt Front 00000000000 A19 GPIB Interface board 9 0000000000000 000000000000 2 20 1 0 board o sooo with RS 232 K ports on rear of N J the board l4 Left side of the measurement set Figure 6 5 Locating audio option boards in the left side card cage Required Tools Use the following tools to remove the Option 40 or Option 41 circuit boa
74. connected to the DSP address and data buses The program memory the instructions for the DSP may be held in either 16K X 4 or 64K X 4 memory parts Jumper connections on the board select the correct device memory size for the parts installed These memories are the X data memory for the DSP and the Y data memory The DSP also has some small internal P X and Y memory These three internal memories P X and Y can be accessed at the same time by the DSP Access to the external P X and Y memories is one at a time These memories are used mainly for storing look up tables and data and results for example fft and other intermediate results are stored here The program instructions are loaded into the P memory from the audio processor The usual action is for the audio processor to set the RESET bit to keep the DSP shut off and download the instructions into P memory Then the RESET is removed and the DSP executes the newly loaded code Each memory device has three memory control lines WE write enable CE chip enable and OE output enable All memory devices are output enabled at the same time the read enable signals determine which memory is actually accessed by the DSP VM700T Video Measurement Set Service Manual Theory of Operation Audio Analog Board 13 Input Amplifiers Signal Input Stepped Attenuator Input Amplifier The following paragraphs discuss the Audio analog board Refer to Figure 3 15 as you
75. cord removed from electrical mains The instrument should be cleaned often enough to prevent dust or dirt from accumulating Dirt acts as a thermal insulating blanket that prevents effective heat dissipation and can provide high resistance electrical leakage paths between conductors or components in a humid environment Use the following tools to clean the instrument Clean nonabrasive lint free cloth m Nonabrasive liquid glass cleaner Isopropyl alcohol W Static free vacuum cleaner with small brush attachment Cleaning the Exterior Clean the dust from the outside of the instrument by wiping with a soft cloth You may use a brush to remove dust from around the selector buttons knobs and connectors Hardened dirt may be removed with a cloth dampened in water that contains a mild detergent or non abrasive glass cleaner Abrasive cleaners should not be used Cleaning the CRT Touch Screen Clean the CRT touch screen by carefully applying a small quantity of glass cleaner and wiping the screen dry with a clean nonabrasive lint free cloth Cleaning the Front Bezel Air Filters At regular intervals inspect the air filters through the front bezel air intake slots for accumulated dust Carefully vacuum the front of the instrument to remove any accumulated dust Cleaning the Interior Use low pressure dry air to remove accumulated dust and dirt high velocity air can damage some parts Hardened dirt or grease may be remove
76. data from the A D converter and the Frame Out and Line Out signals VM700T Video Measurement Set Service Manual 3 13 Test Equipment Depot 800 517 8431 99 Washington Street Melrose MA 02176 FAX 781 665 0780 TestEquipmentDepot Theory of Operation Filter Switch Board A4 Filter Select and Control Slot 0 Slots 1 5 Output Amplifier The filter switch board performs analog filtering of the video signal Filtering is performed by one of five filters mounted as daughter boards on the main circuit board The video signal is intercepted on the analog input board just after channel selection and then returned for analog processing offset gain and dither Figure 3 4 shows the filter switch board block diagram The filters are NTSC band width limit Chroma bandpass IEEE low pass differentiated step and low frequency noise The acquisition controller board provides inputs to the filter select and control block After decoding these inputs select and control the desired filter Note that only the low frequency noise filter has controllable characteristics This block also requests a six bit filter ID from the filter in each slot and transmits it to the acquisition controller board The filter select and control block provides three types of outputs m Filter selection m Filter poll a request for filter I D m Filter control used only by the low frequency noise filter Slot 0 is the straight through path of t
77. for Bar and 0 5 or NTC 7 Combination when Zero Carrier is not IRE for no Zero Carrier and used and 20 to 130 IRE no Bar when Zero Carrier and Bar are not used Multiburst Packet 0 to 10096 of Flag 1 of Flag FCC Multiburst Amplitudes or NTC 7 Combination Table 1 79 Incidental Carrier Phase Modulation Measurement Range Accuracy Measurement specifications ICPM requires Zero Carrier Pulse and the FCC or NTC 7 Composite quadrature output of the demodulator on channel C 1 28 VM700T Video Measurement Set Service Manual Specification Table 1 80 Color Bar measurements Measurement Color Bar Amplitude Errors Color Bar Phase Errors Color Bar Chrominance to Luminance Gain Ratio 100 of nominal FCC Color Ba 180 from nominal FCC Color Bars 0 to 200 of nominal FCC Color Bars Table 1 81 Out of Service measurements Measurement Field Time Distortion 0 to 40 Field Square Wave Table 1 82 Waveform Distortion measurements Measurement Line Time Distortion Pulse to Bar Ratio Short Time Waveform Distortion IEEE 511 Chrominance Nonlinear Gain Distortion Chrominance Nonlinear Phase Distortion Chrominance to Luminance Intermodulation 2T K Factor Table 1 83 VIRS measurements Measurement VIRS Setup Reference Black VIRS Chrominance Reference Amplitude VM700T Video Measurement Set Service Manual 0 to 40 of Bar FCC or NTC 7 Composite 10 to 125 FCC or NTC 7 Composite
78. for channel B and channel C 6 Disconnect the VAC from the measurement set VM700T Video Measurement Set Service Manual 4 7 Performance Verification 4 8 Measure Sinewave This procedure is to be used as a check for proper measurement set system level adjustment It checks the frequency response flatness over the instrument s operating range Test Equipment Required Leveled sine wave generator 75 Q output impedance output flat within 0 025 dB 20 3920 to 6 MHz Example HP 3336C with option 005 m Termination 75 Q precision BNC Tektronix 011 0102 01 or equivalent Coaxial cable 75 Q high quality noise free 1 meter length Tektronix 012 0074 00 Procedure Measure Sinewave 1 Connect the leveled sine wave generator output to the measurement set channel to be tested start with channel A Terminate the channel loop through output connection in 75 Q 2 Set the leveled sine wave generator for 50 kHz at an output level of 500 mV into 75 Q NOTE If the example leveled sine wave generator is being used the output level should be set for 3 81 dBm 3 Press the Measure hardkey then if necessary display the measurement set Diagnostics directory by pressing the Diags soft key In diagnostics run the sine wave measurement application by pressing the Measure Sinewave soft key 4 After the measurement application has initialized turn Averaging on by pressing the Average hardkey until the Avera
79. for the VM700T Video Measurement Set at the time of printing of this manual The Standards options refers to the television standard either Option 01 NTSC or Option 11 PAL for which measurements are made The application options make the appropriate measurements for the installed television standard Standard Options Option 01 and Option 11 When ordering the VM700T you may specify the video standard you what your instrument to be capable of making measurement with Option 01 is the System M NTSC video standard and Option 11 is the System BG i PAL video standard You may also order the VM700T with both standards installed or purchase a firmware upgrade to add a standard to make the VM700T a dual standard Video Measurement Set Application Options Option 1G Option 20 Option 21 Option 30 Option 42 2T Echo and Rounding of Black and White Measurement Option 1G Teletext Measurement Option 20 Camera Measurements Option 21 The application options provide additional measurement capabilities not provided in the standard Option 01 NTSC or Option 11 PAL firmware as part of the base instrument measurements These may be ordered as part of the original purchase or added later with an option upgrade The VM700T Video Measurement Set Option 1G 2T Echo and Rounding of Black amp White gives you access to two measurements named Echo and Rounding Errors respectively Echo determines multipath distortion Rounding Errors
80. from the measurement set 2 Press the Measure hardkey and touch the Video soft key if necessary to recall the Video measurement menu 3 Touch the Burst Frequency soft key With no signal applied the measure ment set displays a warning message that tells you to check the signal source because a signal cannot be found The burst frequency measurement starts automatically after 3 seconds the Loss of Sync indicator blinks VM700T Video Measurement Set Service Manual Performance Verification 4 Press the Menu hardkey and touch the Reference soft key in the menu display 5 Touch the Zero Set soft key to set the measurement reference for the internal oscillator 6 Connect the signal generator full field and burst to the channel A input terminate the loop through with a 75 Q BNC termination 7 Check that the burst frequency measurement is 0 10 Hz using the internal frequency reference NOTE If the measurement result obtained is outside of the specification limits go to Adjusting the Genlock Voltage Controlled Oscillator on page 5 3 in the Adjustment Procedure section VM700T Video Measurement Set Service Manual 4 11 Performance Verification 4 12 VM700T Video Measurement Set Service Manual ae Audio Option Verification Procedure The procedures in this section are designed to verify the operation of the VM700T Video Measurement Set Audio Option 40 and Audio Option 41 Before perfo
81. interconnec tion diagram to assist in faulty module isolation procedures Replaceable Mechanical Parts List has exploded views and gives the lists of the replaceable mechanical parts to aid in locating a replacement mechanical part The assembly Tektronix part numbers are also included in this list as a convenience VM700T Video Measurement Set Service Manual xix RE S Specification The performance limits in this specification are valid with the following conditions This instrument must have been calibrated adjusted at an ambient tempera ture between 420 C and 430 m The instrument must be in an environment with temperature altitude humidity and vibration within the operating limits described in this specification The instrument must have had a warm up period of at least 20 minutes m The instrument must have had its signal path compensation routine last executed after at least a 20 minute warm up period at an ambient temperature within 5 C of the current ambient temperature Any conditions that are unique to a particular characteristic are expressly stated as part of that characteristic Electrical Characteristics Table 1 1 Input characteristics Characteristic Performance requirement Supplemental information Channel A B and C User selectable Differential A B A C B A B C C A and C B may also be digitized for parallel component testing Input Type Loop through BNC connectors Ret
82. is the example Except for the name it is the same for all the high level diagnostic choices 6 74 VM700T Video Measurement Set Service Manual Troubleshooting Procedures NOTE The GPIB diagnostic can be started through the GPIB interface itself execute GPIB Diagnostic but this is not recommended As soon as the GPIB diagnostic starts the interface ceases to talk to the controller To halt the GPIB diagnostic and return to remote control press one of the front panel hard keys Upon exiting the diagnostic the VM700T reboots and an SRQ is asserted A serial poll after the reboot returns the power on status byte 65 There are two run mode choices Power up and Interactive Each diagnostic consists of a series of tests and each series is organized into test families When running individual diagnostics you have two display choices Power Up Mode and Interactive Mode These are described below To run a diagnostic touch the icon representing that diagnostic in the directory window When each diagnostic starts you are prompted to select a run mode from the soft keys at the bottom of the screen as shown in Figure 6 52 The available choices are Power up Mode and Interactive Mode GPIB Diagnostic Select Run Mode Powerup Interactive Mode Mode Figure 6 52 Select run mode the high level diagnostic initial menu Power up Mode Runs the selected diagnostic the same way it would run du
83. level diagnostics run at power up If the VM700T does not complete system initialization because of a fault the diagnostics are not available to assist in isolating the problem In this case you can force Auto Reset mode to ensure that all diagnostic routines run at power up To force Auto Reset mode perform the following steps 1 Power off the VM700T Press and hold the Menu button as you turn the power back on After the VM700T beeps twice release the Menu button to display the VM700T Startup Menu see Figure 6 40 on page 6 66 2 Use the front panel knob to select R in the menu and then press the Select Line button This displays the Instrument Run Modes menu shown in Figure 6 56 3 Use the front panel knob to select A in the Instrument Run Modes menu This restarts the VM700T and runs the full set of internal diagnostics 4 Check that all tests pass as they run If a test fails refer to High Level Diagnostics Test on page 6 78 If the VM700T diagnostics detect a problem the Console and the Diagnostic Errors files may contain information useful for troubleshooting a problem Both files can be printed using the Print File soft key Console File Whenever the VM700T initializes information is stored in the console file located in the directory the topmost If a malfunction causes the VM700T to auto reset the console file could contain useful information The console file is rewritten each time the VM700T is powered on Comp
84. list cont Fig amp index number 10 4 1 2 3 20 21 22 24 25 26 27 28 29 30 Tektronix part number 390 1020 03 390 1020 05 211 0658 00 390 1023 01 390 1023 02 211 0658 00 390 1022 01 390 1022 02 211 0658 00 367 0366 00 211 0755 00 213 0940 00 354 0025 00 210 0894 00 351 0104 03 210 0458 00 351 0636 00 390 1020 04 211 0658 00 390 1025 01 390 1025 02 211 0658 00 390 1028 01 390 1028 02 211 0658 00 390 1021 03 390 1021 05 211 0658 00 390 1021 01 348 0879 01 211 0538 00 348 0596 00 200 3634 01 161 0066 00 011 0102 03 348 0080 01 174 3726 00 070 9647 XX 070 9650 XX 159 0005 00 210 0863 00 343 0136 00 Serial no effective B010100 B030100 B010100 B030100 B010100 B030100 B010100 B030100 B010100 B030100 B010100 B030100 Serial no discont d B029999 B029999 B029999 B029999 B029999 B029999 Qty Name amp description 2 qo qo oe MOH HB HP BA Be hw Be Pp n on CABINET COVER RACK MOUNT TOP amp BOTTOM CABINET COVER RACK MOUNT TOP amp BOTTOM SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ CAB SIDE ASSY LEFT RACK MOUNT CAB SIDE ASSY LEFT RACK MOUNT SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ CAB SIDE ASSY RIGHT RACK MOUNT CAB SIDE ASSY RIGHT RACK MOUNT SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ HANDLE CARRYING VM700T SCREW MACHINE 10 32 X 0 5 PNH POZI THUMBSCREW 10 32 X 1 15 0 375 OD SST RING RETAINING EXTERNAL
85. manual modes The parameter files are reached through the directory and file structure accessed by the Configure button Freeze Source Selection and Average Functions The second row in the keypad contains the Freeze button the input channel selection buttons grouped as SOURCE A B and C and the Average button m Freeze Button When you select Freeze signal acquisition is halted The display can be moved expanded or contracted as described below under Control Knob but the display is not updated m Source Selection Button For all operational modes one of the input sources is always selected For some of the manual modes an input source can be inverted In Waveform and Vector modes an inverted source can be the sole input or it can be added to another input In Measure mode an inverted source can only be added to another source m Source Invert To invert a single source press and hold the source button until the measurement set beeps approximately one second When a source 15 inverted the LED on the source button flashes To invert a second source and add it to another press and hold the normal source and while holding it quickly press and release the inverted source The LED on the inverted source will flash m Average Button The Average button enables uncorrelated or random noise reduction on the signal in Waveform and Vector modes and averaging of the signal in Measure mode The amount of noise reduction up to 30
86. measures rounding of the black to white and white to black signal transitions The VM700T Video Measurement Set Option 20 Teletext gives you access to two measurements Teletext and SoundInSync These measurement applications determine various parameters related to the transmission of digital information in the vertical interval and in the sync pulse respectively The following Camera Testing measurements are available with Option 21 of the VM700T Video Measurement Set Colorimetry measures the color fidelity of a camera s output CCD or tube cameras Defects identifies defective cells in CCD devices CCD cameras only VM700T Video Measurement Set Service Manual 7 1 Options Component Measurements Option 30 Detail measures the artificial sharpening transitions added to the video in both the horizontal and vertical directions as a percentage of transition amplitude CCD or tube cameras m Fixed Pattern Noise identifies unwanted signal non uniformities correlated to CCD cells CCD cameras only Frequency Response measures the degradation in waveform amplitude as the frequency of modulation increases CCD or tube cameras Measures aliasing components for CCD cameras m Gamma measures the input to output light transfer characteristic of an imaging or display device CCD or tube cameras m Geometry and Registration measures geometric distortions in camera imaging elements CCD or tube cameras Shad
87. module is field removeable for replacement only it is not a field serviceable unit 1 Perform the following steps to remove the power supply a Remove the instrument cover panels refer to Cover Panel Removal and Replacement on page 6 8 b Position the VM700T with its bottom facing up and remove the wires and connectors from the power supply Disconnect the wires to the On Off switch from the switch NOTE The connections are labeled on the power supply You should also tag each wire with a label as you remove it for easy replacement later c From the instrument bottom remove four attaching screws one screw is accessed through a slot in the power supply housing See Figure 6 24 VM700T Video Measurement Set Service Manual Maintenance d Atthe rear panel remove five retaining screws e Move power supply to clear the corner rail overhang and holding the wires aside carefully lift it straight up and out of the VM700T chassis f Remove the cable to the On Off switch from the power supply y X X Figure 6 24 Removing the power supply retaining screws 2 Replace the power supply by performing step 1 in reverse order CAUTION When replacing the power supply make sure the replacement power N supply line voltage switch is set to the correct line voltage If the line voltage switch is not set correctly the VM700T a
88. ns on the horizontal scale See Figure 5 13 y Touch the Horz Pos 360 Mbit soft key to save the adjustment A wait message will appear 5 30 VM700T Video Measurement Set Service Manual Adjustment Procedure Z Press the VM700T front panel Menu button aa Touch the Waveform soft key and then deselect the Falling Edge and Non Transitn soft keys leave only Rising Edge selected ab Touch the Calibrate soft key and then touch the Delay4 soft key ac Turn the front panel knob to center the displayed rising edge of the signal See Figure 5 14 ad Touch the Delay4 soft key to save the adjustment A wait message will appear ae Slide back the right side cover to access the CPU board dip switch af Set switch 4 of the dip switch to closed and then slide the cover forward to enclose the circuitry See Figure 5 12 on page 5 28 ag Press the VM700T front panel Menu button ah Touch the Waveform soft key and then touch the Full Signal soft key 270Mb 525 line Auto detect F2 L97 scanning mv Eye Diagram f 500 400 p i 300 f tul Fi P 200 f M 100 5 E f Adjust distances A and B i DOM f to the same size f 200 f f 300 rl A00 dass i 500 x d e UN td i 0 0 0 2 0 4 0 6 0 8 1 0 1 2 Unit Intervals DC OffsetlO 5 mv 8281 22 meters Cable Len Bel Filter 1
89. on power up The remaining choices are used in diagnostic testing in manufacturing and factory service When a selection is made the choice is stored in the diagnostics NVRAM and the Diagnostics Configuration menu returns At this point the quickest way to start the instrument for normal operation is to turn off the VM700T and turn it back on again You can also use the Abort Menu selection to back up the menu tree to the VM700T Startup Menu and then select one of the run modes to restart the VM700T Low Level Diagnostic Interface knob moves cursor Select Line inputs selection SET DIAGNOSTICS POWERUP MODE Select a Powerup Mode from the list below The mode selected will be stored in Diag NVRAM and will be effective for NORMAL powerups ie Boot Switches in NORMAL position The current Powerup Mode setting is STARTUP MENU Key Selection QUICK STAR mm nm Skip Diagnostics start Instrument M STARTUP MENU s Goto VM700T Startup Menu P POWERUP 0 1 0 Do Diagnostics start Instrument L LOW LEVEL DIAGS LOOP Loop on Low Level Diagnostics D HIGH LEVEL DEBUG Run Instrument in DEBUG MODE Reprint Abort Menu Input your selection Figure 6 48 Set diagnostics power up mode menu Bypassing the Boot Switch Power Up Mode The boot switch can be set to start in various power up modes for Factory Service use in troubleshooting and testi
90. only After exiting the stepped attenuator the signal is applied to an input clamp circuit The clamp circuit 11 2 V input clamping protects the operational amplifier by holding its input below the supply voltage low noise performance can be degraded or circuit devices can be damaged if input voltage exceeds supply The nominal signal expected at the input to the amplifier is approxi mately 3 5 V peak just over 2 V rms The positive half and negative half of the differential signal are applied to operational amplifiers that form an instrumentation amplifier This is normally a unity gain stage but it has selectable gain of 10 dB and 20 dB The attenuator preceding can be 0 no attenuation 10 dB or 20 dB The differential input VM700T Video Measurement Set Service Manual 3 37 Theory of Operation signal is converted to a single ended signal and common mode voltage is suppressed or cancelled Calibration DAC Control From Processor Gain amp Offset CAL Serial LEFT OU ut INPUT 9 Balanced Differential ADC Input 400Hz Notch Overload NORM Amplifier Filter Gain Protection Filter SELECT SELECT 0 10 20dB 0 10 20dB INPUT Balanced pa ut Notch C NORM Amplifier ilter Protection Filter 6 144 MH divide by 3 2 Master 18 432 MHz i Oscillator divide by 8 2 304 MHz divide by 64 3 072 MHz
91. or a high precision 5 V reference and is chopped at 120 Hz The symmetrical square wave developed by the switching is applied to the selected analog input through a coupling capacitor Capacitive coupling shifts the DC level of the signal to 2 5 V When the chop signal is not running the output is at ground Calibration Channel Selection A set of relay contacts determine the channel and side of the differential channel input that the calibration signal is applied to The calibration selections signals drive this set of relays In the unenergized state channel 1 gets the calibration signal The unselected channel is grounded Other relays switch the sense of the calibration signal so that both sides of the balanced differential inputs may be calibrated using the single ended calibration signal During calibration the noninverting input is calibrated first grounding the inverting input When that half is finished the relays switch to apply the calibration signal to the inverting input to calibrate that side VM700T Video Measurement Set Service Manual 3 39 Theory of Operation Option 40 A D Converter Input Clamp CH 2 and CH 1 Amplifier Audio Board Control 3 40 AJD Converter Opto Isolators The channel 1 and channel 2 circuits are identical only the channel 2 circuit is discussed here The channel 2 signal is applied to a clamp circuit at the input of the amplifier This clamp circuit protects the input of the A D c
92. output of the ADC provides calibration information that is stored in a look up table The VM700T uses the look up table information to maintain its luminance accuracy specification without the need for periodic readjustments VM700T Video Measurement Set Service Manual 3 5 Theory of Operation Sync Selection DVM Selection and DVM 3 6 The VM700T gets sync from one of two sources directly from the channel A B or C loop through inputs from the external sync loop through input To maintain a high impedance level for the video loop through inputs the sync selection buffers the selected signal Following the sync selection is an amplifier that returns the video to the nominal one volt level required by the sync stripper circuitry on the genlock board The sync stripper needs a negative going sync pulse To enable the instrument to lock to inverted video the amplifier following the sync selection can be programmed to invert the inverted video selected as the sync source push down the front panel SOURCE A B C button for about one second to invert the video NOTE Video appears on the display in whatever orientation inverted or non inverted it appears at the input connector When you push the SOURCE A B C button only the video used as the sync source is inverted The DVM measures the average picture level APL The VM700T measures the analog average as the video exits to the filter switch board This analog voltage
93. overall system response If the verification checks fail the system may need readjustment The adjustments provided are to compensate the system frequency response after a board replacement they are not complete board level adjustments Use the adjustments only as necessary to return the instrument to specification NOTE This procedure requires precision test equipment to make the needed measurements for alignment If you do not have the required test equipment it is recommend that you have the adjustment procedure done by Tektronix Customer Service Contact your nearest Tektronix representative for information Test Equipment Required m Gain phase analyzer 75 output impedance Example Hewlett Packard 4194A Impedance Gain phase analyzer m Leveled sine wave generator 75 Q output impedance output flat within 40 025 dB 0 3 to 6 MHz Example Hewlett Packard 3336C Sine wave generator with option 005 W Coaxial cable 75 2 high quality low noise BNC 1 meter length 2 each Tektronix part number 012 0074 00 m Termination 75 Q feed through BNC Tektronix part number 011 0055 01 m Termination 75 precision BNC Tektronix part number 011 0102 01 m Female to female adapter BNC Tektronix part number 103 0070 00 Adapter snap on SMB male to BNC female 2 each Example Omni Spectra part number 3280 2224 00 m Non metallic flat blade adjustment tool Tektronix part number 003 1364 00 Specification Checked
94. pins 4 and 5 replace the SDI board If the time code signal is not present remove the SDI Rear Panel Interface assembly Disconnect the flat cable from the SDI Rear Panel Interface assembly and then check each of the 10 wires in the cable for continuity If the cable is good replace the SDI Rear Panel Interface assembly VM700T Video Measurement Set Service Manual 6 103 Troubleshooting Procedures No Signal From the SDI Output Connector Perform the following steps when the SDI Output connector provides no signal but the SDI Ch A and SDI Ch B inputs operate 1 Connect a digital video signal to the SDI Ch A input and terminate the loopthrough connector 2 Connect a cable from the SDI Output connector to the SDI Ch B input 3 Check that you can display the SDI Ch B signal on the VM700T NOTE Set the Source Selection Digital configuration file to output the selected channel to the SDI Output connector 4 Ifthere is no signal display disconnect the cable from J10 on the SDI board see Figure 6 65 5 Check the center pin of the J10 connector for a digital video signal 6 Ifthe video signal is not present replace the SDI board 7 Ifthe video signal is present replace the SDI Output cable SDI Option Diagnostics Running the Option 1S 6 104 Diagnostics Option 1S is composed of three modules and two sets of interconnects see Figure 6 66 The SDI and the Acquisition Controller diagnostic
95. read the discussion This section discusses the channel 2 right channel input amplifier but the channel 1 left channel input amplifier circuitry and function is the same The input amplifiers are labeled on the board s back panel The channel 2 analog signal enters the board through a 3 pin mini XLR connector on the VM700T back panel This connector is a balanced differential input From the input the analog signal is applied to NORM CAL relay In normal operation the relay is not energized and the signal passes through Cal operation is described later The audio differential signal is AC coupled to remove DC offset from the input signal NOTE On option 41 boards the analog signal enters through pins on a DB37 connector rather a mini XLR connector On Option 41 boards relays select one of the three different inputs for each channel The control signals for these relays travel on the audio signal ribbon cable but control and signal lines are isolated by ground runs From the coupling capacitors the signal is applied to an attenuator circuit Each step of the attenuator is 10 dB The default position provides unity gain no attenuation Attenuation steps of 10 dB and 20 dB are selectable The top of the range at unity gain is 10 dBu With a 10 dB attenuator it is 20 dBu and with the maximum attenuation it is 30 dBu NOTE Load resistance is not considered in measuring dBu Similar to dBm dBu is voltage referenced
96. screw holes in the box Place the box in any convenient location within the rack where you can make the power cord connections see Figure 2 1 NOTE Do not mount the power line conditioning box in any location that blocks the air flow in or out of the VM700T or any other product installed in the rack VM700T 9 9 00000000 0000 VM700T Power line conditioner Install at a convenient location within the rack 230VAC mains power strip O 000000 0 Figure 2 1 Power line conditioner with a rackmounted VM700T VM700T Video Measurement Set Service Manual 2 3 Operating Information Power On Diagnostics Benchtop Mounting For a standalone VM700T on a benchtop or for portable use apply the four adhesive rubber feet provided with the accessory to the bottom of the box at the corners Place the conditioner box in a convenient location where you can make the power cord connections Power Cord Connections Connect the Power Line Conditioner in the power line between the AC mains and the VM700T power input connector in the following order 1 Plug the output power cord connected to the box into the AC power input connector of the VM700T 2 Plugthe AC mains power cord into the AC input connector of the power line conditioner box 3 Plug AC mains power cord into the 230 Vac mains source The measurement s
97. the Diags soft key to switch to them m Touch the DiagsLoop soft key to loop the selected continuously Use the Abort Looping soft key to halt diagnostic looping at the end of the warm up period Return to the Configure menu and check the Diagnostic Errors file for new errors Refer to the Diagnostics information in the Maintenance section of this manual for more information on the diagnostics tests and their operation Audio Limit Audio Source Audio Source Files Files Identification Auto Limit Camera Communication Files Testing Setup Diagnostics Diagnostic component Selection Errors Echo Rounding Measure 111 Measunement 2 Files Locations NTSC Files In nvram ConfigFiles Switch Print Leave NTSC PAL File Directory Figure 4 3 Configure directory Selecting High Level Diagnostics All diagnostic routines on the Selected side execute during Powerup Diagnos tics if not set to Quick Start and when DiagsLoop is selected To select or unselect a diagnostic from the Diagnostics Selection file 1 Press the Configure button 2 Press the Configure Files soft key 3 Select the Diagnostics Selection file 4 Turn the control knob until the name of the diagnostic is highlighted Touching the vertical center of the left half of the screen sel
98. the four times subcarrier 4Fsc clock from the phase locked loop or the 20 25 MHz crystal clock A transparent latch stops the clock output when changing sources ensuring a smooth transition between them Line strobe output multiplexer selects either composite sync or the window pulse from the phase locked loop and converts it into a pulse one sample clock period in duration Frame strobe output A multiplexer selects either the decoded frame pulse from the frame decoder or the synthesized frame pulse and converts it into a pulse one sample clock period in duration Control An 8 bit read write register is used for mode control Control bits select the video standard sampling mode frame mode and sound in sync SIS mode Logic provides enables for various hardware functions with LEDs on the circuit board to indicate which of them are in use Status An 8 bit read only register is used to read genlock status Some of the bits indicate the current lock status and history The remaining bits indicate VCO on off status and the genlock hardware revision level LEDs on the circuit board indicate the current lock status and whether any unlocks have occurred since the last read of the status register 3 10 VM700T Video Measurement Set Service Manual Theory of Operation The Analog to Digital ADC Board 2 5 V and 2 5 V Regulators Signal Conditioning Amplifier AJD Converter Buffer Output Latch The 2 5 V and 2
99. to make a repair Before You Troubleshoot If you suspect that Option 1S is not operating properly perform the following steps before you perform the troubleshooting procedures 1 Verify that the VM700T is set to Mode Digital NOTE The VM700T must be set to Mode Digital before you can access any Option 1S functions You cannot access any Option 1S functions if the VM700T is set to Mode Analog 2 Verify that all Option 1S and VM700T diagnostics pass refer to SDI Option Diagnostics on page 6 104 3 Inspect the rear panel connectors for damage 4 Inspect the internal cable connections between the SDI Rear Panel Interface assembly and the SDI board and the cable between the SDI board and the Acquisition Controller board The instructions for isolating the SDI option faults listed below are found on the following pages m No signal from the SDI Ch A input m No signal from the SDI Ch B input No signal from the Analog Ref input m No signal from the AES EBU Digital Audio input m No signal from the LTC Time Code input m No signal from the SDI Output connector Perform the following steps when the VM700T will not display a known signal on the SDI Ch A input 1 Connect a digital video signal to the SDI Ch A input and terminate the loopthrough connector 2 Setthe VM700T to display the channel A signal using the SDI Waveform application VM700T Video Measurement Set Service Manual Troubleshooting
100. to permit a rack p mounting installation Cabinetizing Kit This field installable option provide a conversion kit to install a cabinet on a rack VM7FC1 mounted measurement set Auxiliary Software Options VMBKUP VMT VMREMGR VMBKUP This software package assists in backing up the VM700T user created files These files can be reloaded to the same instrument or to another VM700T to generate a common set of configuration files This software package assists in remote control of the VM700T using a personal computer The software also allows you to capture text and graphics VMREMGR This software package aids you in handling the graphic displays and transferring them to a personal computer for filing display or printing Optional Accessories Table 7 1 Optional accessories Tektronix part or Accessory Description product number Service manual VM700T servicing information 070 9630 XX GPIB accessories Available with Option 48 Cables 1 m double shielded 012 0991 01 2 m double shielded 012 0991 00 3 m double shielded 012 0991 02 GURU 11 GPIB User s Resource Utility for the IBM Personal Computer This package S3FG100 includes software and manual plus National PC2A GPIB controller board GPIB cable software on floppy diskettes VM700T Video Measurement Set Service Manual 7 5 Options Power Cord Options Table 7 2 Optional power cords Plug configuration North America Standard 125 V 15A Plug
101. wire at J933 only installed on instruments with serial numbers below B050100 Figure 6 22 Orienting connector J933 for installation on the Keypad board serial numbers below B050100 CRT Touch Panel Use the following procedure to remove and replace the CRT touch panel l Perform the following steps to remove the CRT touch panel a Remove the CRT bezel refer to CRT Bezel on page 6 32 b Remove the Keypad board assembly refer to Keypad Board Assembly on page 6 34 NOTE It is not necessary to remove the ground wire on the Keypad board assembly if you are removing just the CRT or CRT touch panel c Remove the four nuts that hold the touch panel and then lift the CRT touch panel away from the CRT to remove the touch panel see Figure 6 23 2 Replace the CRT touch panel by performing step 1 in reverse order VM700T Video Measurement Set Service Manual Maintenance CRT Assembly Use the following procedure to remove and replace the CRT assembly 1 Perform the following steps to remove the CRT assembly a Remove the CRT bezel refer to CRT Bezel on page 6 32 b Remove the right side card cage retainer refer to step 1 on page 6 16 c Remove the Keypad board assembly refer to Keypad Board Assembly on page 6 34 NOTE It is not necessary to remove the ground wire on the Keypad board assembly if you are removing just the CRT or CRT touch panel d Remove the CRT touch panel refer to the prece
102. 0 6 VM700T Video Measurement Set Service Manual Replaceable Mechanical Parts Replaceable parts list cont Fig amp index Tektronix Serialno Serial no number effective discontd Qty amp description Mfr code part number 10 2 1 672 1473 00 1 CKT BD ASSY ADC A3 80009 672 1473 00 1 CKT BD ADC A3A1 1 CKT BD ASSY ADC FILTER A3A1A1 2 211 0661 00 7 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 3 Not used 4 Not used 5 Not used 6 Not used 7 Not used 8 Not used 9 211 0008 00 SCREW MACHINE 4 40 X 0 25 PNH STL TK0435 ORDER BY DESC 10 174 1164 00 CA ASSY SP ELEC 10 26 AWG 6 5 L RIBBON 9M860 ORDER BY DESC 11 174 0837 00 CA ASSY SP ELEC 10 18 AWG 14 05 L RIBBON 00779 ORDER BY DESC 12 672 1344 04 B010100 B010169 CKT BD ASSY FILTER SW A4 80009 672 1344 04 672 1344 06 B010170 CKT BD ASSY FILTER SW A4 80009 672 1344 06 BD ASSY FILTER SW WO FILTERS MAT CKT BD ASSY CHROMA BANDPASS FILT 4 1 1 CKT BD ASSY DIFF STEP FILTER A4A1A2 CKT BD ASSY LF NOISE FILTER A4A1A3 CKT BD ASSY IEEE LOWPASS FILTER A4A1A4 CKT BD ASSY NTSC BW LIMIT FILTER A4A1A5 m P 18 Not used 14 211 0661 00 6 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 15 Not used 16 Not used 17 Not used 18 Not used 19 174 2008 00 1 CABLE ASSY RF 75 OHM COAX 3 75 L 0 N TK2469 174 2008 00 20 337 3515 00 1 SHIELD ELEC POLYMIDE 2K262 ORDER BY DESC
103. 0 VAC Input surge current and overvoltage protection components are included in the input rectifier circuit to prevent major component damage in the event that incorrect line voltage is applied to the AC input Housekeeping Power second power supply provides the housekeeping or keep alive power source Supply This supply provides power to the logic circuitry that controls the power supply STBY ON logic circuitry One of the sensing signals LINE SENSE to the power supply logic circuitry is developed from the secondary of the house keeping supply transformer Inverter Switching Circuit This circuitry comprises the Pulse Width Modulator the Switching Transistor Drivers the Switching Transistors and the Secondary Rectifiers and Filters Secondary outputs of the power transformer are full wave rectified and filtered to provide 5 V 5 V 16 5 V and 16 5 V The 16 5 V and 16 5 V are further regulated to produce the 15 V and 15 V supplies to the VM700T and the 12 V display module power The source voltage for the Fan Drive circuit is also provided by the 12 V supply VM700T Video Measurement Set Service Manual 3 31 Theory of Operation Line Voltage Inverter Secondary Switch Rectifier Switching Rectifiers 45 Va Circuit 52 Va lt 5 7 Housekeeping Supply HOUSEKEEPING 15V 12V amp 15V 15V Power Primary Regu
104. 0 family of video measurement sets Substitute test equipment may be used if available Refer to the Minimum Specification column to determine the key specifications needed to verify the accuracy of the VM700T Video Measurement Set The specific pieces of equipment required to perform a procedure are shown at the beginning of that procedure Note that the Gain Phase analyzer is required for the extended adjustment procedure only Table 5 1 Test equipment required for verification and adjustment Equipment Minimum specification Example Video amplitude calibrator Square wave 0 0 mV to Reference standard for Tektronix 067 0916 00 not 999 9 mV peak accuracy amplitude verification currently available for 0 0596 resolution 0 1 mV purchase Leveled sine wave generator 75 Q output impedance Measure sine wave filter Hewlett Packard 3336C output flat within 0 025 dB flatness adjustment Sine wave generator with 0 3 to 6 MHz option 0052 Television signal generator NTSC full field and burst NTSC test signal source Tektronix TSG 170A or equiv capability accurate to 1 Hz alent Television signal generator PAL full field and burst PAL test signal source Tektronix TSG 271 or equiva capability accurate to 1 Hz lent Frequency counter External reference capability Adjust the GenLock VCO Tektronix DC 503A TEGAM or ratio A B 8 digit display DC 503A or equivalent Digital multimeter DC Volts range 20 mV to Adjust the GenLock VCO Tekt
105. 0 mV nominal 30 to 70 0 3 B2 CCIR Rec 569 700 mV nominal 0 to 90 of 0 3 B2 and Zero Carrier Maximum Carrier 0 to 90 of B2 and Zero Carrier Live picture area Maximum Carrier 0 to 90 of Zero Carrier CCIR Rep 624 1 75 of bar G1 or G2 CCIR Rec 569 amplitude 300 ns 5 ns F or G1 or G2 CCIR Rec 569 0 ns nominal 20 to 110 2 CCIR Rec 569 05Vto2V B2 CCIR Rec 569 VM700T Video Measurement Set Service Manual Specification Table 1 41 Amplitude and Phase measurements cont Measurement Burst Quadrature Error Differential Gain Peak and p p Differential Phase Peak and p p 0 to 100 096 nominal 0 to 360 0 nominal CCIR Rec 569 CCIR Rec 569 Table 1 42 Frequency Response measurements Measurement MultiBurst Flag Amplitude MultiBurst Amplitude 60 nominal 21 596 of flag CCIR Rec 567 2 596 of 5 8 MHz packet 0 to 20096 of flag 100 nominal Table 1 43 Waveform Distortion measurements Measurement Baseline Distortion 2T Pulse Bar Ratio Error 2T Pulse K factor Bar Tilt End Points Bar Tilt Peak to Peak Line Time Distortion Bar Tilt Rec 569 Field Time Distortion Chrominance Luminance Intermodulation Luminance Non linear Distortion 42596 to 90 0 596 CCIR Rec 569 096 nominal 0 3 Kf Moo o CCIR Rec 569 0 to 10 Kf 096 Kf nominal 0 to 40 20 296 B2 CCIR Rec 567 096 nominal 0 t
106. 0 to 25 SD 0 5 SD NTC 7 Composite 5 IRE to 35 IRE 0 4 IRE NTC 7 20 IRE chroma Combination 45 IRE to 160 IRE 80 IRE chroma 0 to 360 1 0 NTC 7 Combination x50 IRE 0 2 IRE NTC 7 Combination 0 to 10 Kf 0 3 Kf FCC or NTC 7 Composite 20 to 130 of Bar 0 2 0 5 IRE when Bar VIRS 20 IRE to 130 IRE when 15 not used Bar is not used 0 to 200 of burst ampli tude 0 to 8096 of Bar when burst is not used and 0 IRE to 80 IRE when burst and bar are not used VIRS 1 0 196 when burst is not used and 1 IRE when burst and bar are not used 1 29 Specification Table 1 83 VIRS measurements cont Measurement VIRS Chrominance Phase Relative to Burst VIRS 30 to 100 of Bar 80 IRE to 100 IRE when bar is not used VIRS Luminance Reference Table 1 84 Signal to Noise Ratio measurements Measurement Unified Unweighted SNR Unified Luminance Weighted SNR 26 dB to 60 dB 61 dB to 70 dB NTC 7 Unweighted SNR 26 dB to 60 dB 61 dB to 70 dB NTC 7 Luminance Weighted SNR 26 dB to 60 dB 61 dB to 70 dB Periodic SNR 1 30 0 2 0 2 IRE VIRS 26 dB to 60 dB 1 0 dB Quiet Line 61 dB to 70 dB 2 0 dB 1 0 dB Quiet Line 2 0 dB 1 0 dB Quiet Line 2 0 dB 1 0 dB Quiet Line 2 0 dB 26 dB to 60 dB 1 0 dB Quiet Line 61 dB to 70 dB 2 0 dB VM700T Video Measurement Set Service Manual Specification Audio Option 40 Option 41 and Option 42 Specifications
107. 00T Video Measurement Set Service Manual f 48 TERRITI T Figure 10 1 Front assemblies and power supply 10 15 VM700T Video Measurement Set Service Manual 10 16 VM700T Video Measurement Set Service Manual Figure 10 2 Circuit boards 10 17 VM700T Video Measurement Set Service Manual 10 18 VM700T Video Measurement Set Service Manual S Figure 10 3 Chassis assembly 10 19 VM700T Video Measurement Set Service Manual 10 20 VM700T Video Measurement Set Service Manual Figure 10 4 Cabinet and accessories VM700T Video Measurement Set Service Manual 10 21 10 22 VM700T Video Measurement Set Service Manual E MT E MI AAA M S KP 07 Figure 10 5 Option 1S circuit boards 10 23 VM700T Video Measurement Set Service Manual 10 24 VM700T Video Measurement Set Service Manual 1 1 10 12 D or A17 a P695 VM700T Video Measurement Set Service Manual A19 AT A1 F1 F1 F100 A5 A20 x Fuse located on the back of board tab U48 050 A11A2 front of board Figure 10 6 Circuit board fuse locations 10 25 10 26 VM700T Video Measurement Set Service Manual Test Equipment Depot 800 517 8431 9
108. 00T front panel Menu button Select Rate Frame if necessary using the Rate soft key Select Filter 10 Hz if necessary using the Filter soft key Touch the Cursors Units soft key Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 50 Hz as read in the readout Check that the Spectrum Cursor 1 amplitude readout is 2 4 to 8 4 dB Check that the Timing p p readout is 1600 to 2600 ps VM700T Video Measurement Set Service Manual SDI Option 1S Verification Procedure 2 Perform the following steps to check the Jitter application at 270 Mb and 580 Hz a g h Adjust the digital television signal generator for a jitter frequency of 580 Hz and a jitter amplitude of 2 ns on the signal output Press the VM700T front panel Menu button Select Filter 1 kHz using the Filter soft key Touch the Rescale soft key and then touch the Cursors Units soft key Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 580 Hz as read in the readout Check that the Spectrum Cursor 1 amplitude readout is 7 4 to 15 4 dB Check that the Timing p p readout is 1600 to 2600 ps Check that the Alignment p p readout is 700 to 1500 ps 3 Perform the following steps to check the Jitter application at 270 Mb and 15 kHz a Adjust the digital television signal generator for a jitter frequency of 15 kHz and a jitter amplitude of 2 ns on the signal outp
109. 0T Video Measurement Set Service Manual Theory of Operation Analog Digital MUX The analog digital MUX selects between the Channel A analog data stream and the digital data stream Audio Video MUX The audio video MUX selects between the analog or digital data stream and the audio data stream It also has the capability to insert the external audio data stream in place of the SDI chrominance samples of the data stream for A V timing measurements of external audio Flag Selection MUX The SDI board has many status lines that can be multi plexed onto the six flag lines into the Acquisition Memory board The flag selection MUX controls this mapping Analog Data Path The analog signal path is comprised of the following blocks as shown in Figure 3 20 High Performance Clock Recovery This block performs the same function as the regular clock recovery function block but it has been calibrated and has a far greater jitter tolerance Jitter Demodulator The jitter demodulator converts timing variations in the recovered clock into an analog voltage Various filters can be selected for the output that goes to the 10 bit ADC Analog Peak Detectors This block tracks the analog control voltage from the jitter demodulator The detectors have rapid charging and slow decay 10 Bit ADC The 10 Bit ADC block is used to generate the samples for the eye diagram and for the jitter waveform When fed the raw SDI signal and clocked by the output of th
110. 0T Video Measurement Set Service Manual Troubleshooting Procedures CAL DAC Bias and A1 Analog Input Acquisition Data Path A4 Filter Switch Acquisition Aid Clampin iis Input Select Acquisition Data Data Path Ink Gain Path Aic Acquisition Data Path Dynamics Control gt Dynamics Control Dynamics Control 8 bit Offset 5 bit Gain 6 bit Dither A2 Genlock Genlock NTSC VCO PAL VCO A2a Synch Detect A2b Frame Detect A2c Acquisition Data Path Timing Data State Dynamics RAM A18a Acquisition Machine A18 Acquisition Memory Dynamics Control Access lt lt Acquisition Data Path Controller Access Synch State Machine Frame Trigger RAM amp 18 E A18b e Acquisition Data Path S Timing Data E DVM 184 lt Acquisition Data Path Acquisition Data Path 1 A18f Access Accessory Board s Audio GPIB etc Figure 6 55 High level diagnostics test blocks VM700T Video Measurement Set Service Manual A5 CPU a Acquisition Acquisition Data Path Data i th Front Panel Display Aba Display Memory Aba NVRAM 54 ROM Acquisition Data Path Access 1 Acquisition Data Path Front Panel CPU Abg Access F
111. 1 Coaxial cables 75 Q high quality noise free BNC 1 meter length 2 each Tektronix 012 0074 00 m Non metallic flat blade adjusting tool Tektronix 003 1364 00 NOTE This procedure requires access to a radio frequency standard signal If you do not have access to a radio frequency standard signal do not attempt to adjust the frequency of the VM700T genlock crystal oscillator Specification Checked Genlock VCO within 5 Hz of a radio frequency standard 1 MHz signal when checked with the following procedure Single standard instruments either NTSC or PAL need only one VCO checked For dual standard instruments both the PAL and the NTSC VCO must be checked Verifying the Genlock Voltage Controlled Oscillator 1 Connect a radio frequency standard 1 MHz signal to the external reference input of the frequency counter channel B of the example counter 2 Connect the subcarrier output of the appropriate video signal generator NTSC or PAL to the signal input of the frequency counter channel A of the example counter 3 Using the suggested frequency counter the ratio of the channel A to channel B signal is used to determine when the frequency of the test signal is adjusted correctly Adjust the signal generator until the frequency counter displays the exact TV standard subcarrier frequency for the VCO being checked 3 579545 MHz for NTSC or 4 43361875 for PAL 4 Connect the composite video output of the signal gen
112. 1 1 2 1 3 1 4 1 4 1 4 1 6 1 7 1 7 1 8 1 9 1 10 1 10 1 11 1 12 1 12 1 13 1 13 1 13 1 13 1 13 1 14 1 14 1 14 1 14 1 15 1 15 1 15 1 15 1 15 1 15 1 16 1 16 1 16 1 16 1 16 1 17 xi Table of Contents xii Table 1 38 Table 1 39 Table 1 40 Table 1 41 Table 1 42 Table 1 43 Table 1 44 Table 1 45 Table 1 46 Table 1 47 Table 1 48 Table 1 49 Table 1 50 Table 1 51 Table 1 52 Table 1 53 Table 1 54 Table 1 55 Table 1 56 Table 1 57 Table 1 58 Table 1 59 Table 1 60 Table 1 61 Table 1 62 Table 1 63 Table 1 64 Table 1 65 Table 1 66 Table 1 67 Table 1 68 Table 1 69 Table 1 70 Table 1 71 Table 1 72 Table 1 73 Table 1 74 Table 1 75 Line Blanking timing measurements Field Blanking timing measurements Other Timing measurements Amplitude and Phase measurements Frequency Response measurements Waveform Distortion measurements Low Frequency Error Noise measurements Incidental Carrier Phase Modulation Bar Line Time Bounce Burst Frequency Chrominance to Luminance Gain and Delay Chrominance Frequency Response Chrominance Noise Chrominance Non Linearity ColorBar SMPTE color bar nominal values Differential Gain and Phase Frequency Response and Group Delay Horizontal Blanking Horizontal Timing Incidental Carrier Phase Modulation Jitter uii K Factor Level Meter Line Fr
113. 1 Optional power cords Table 1 12 AC Electrical Characteristics Table 1 13 Power Line Conditioner Mechanical Characteristics Table 1 14 Power Line Conditioner Environmental Characteristics Table 1 15 Bar Line Time Table 1 16 Bounce Table 1 17 Burst Frequency Table 1 18 Chrominance to Luminance Table 1 19 Chrominance Noise Table 1 20 Chrominance Nonlinearity Table 1 21 Color Re y hh Table 1 22 Differential Gain and Phase Table 1 23 Frequency Response and Group Delay Table 1 24 Horizontal Blanking Table 1 25 Horizontal Timing Table 1 26 Incidental Carrier Phase Modulation Table 1 27 Jitter Table 1 28 K Factor Table 1 29 Level Meter Table 1 30 Line Freq lC 5 eese ont ke EX ER due x d Ru Table 1 31 Luminance Nonlinearity Table 1 32 Mul B rst Table 1 33 Noise Spectrum Table 1 34 SCH Phase Table 1 35 Two Field Table 1 36 Vertical B Table 1 37 VITS ID VM700T Video Measurement Set Service Manual lanking eee rU EI RR RIP 1
114. 1 39 Specification Table 1 100 SDI Jitter application cont Characteristic Performance requirement Supplemental information 270 Mb s 360 Mb s 3 dB to 5 MHz 3 dB to 6 dB at 10 MHz 3 dB at 8 MHz typical Timing amp Alignment Jitter Readout Accuracy 143 Mb s 200 ps 20 of actual for components from 100 ps 5 of actual for components from 50 Hz to 1 MHz 50 Hz to 1 MHz typical 200 ps 2096 30 of actual for components from 1 MHz to 3 MHz 270 Mb s 360 Mb s 200 ps 20 of actual for components from 100 ps 5 of actual for components from 50 Hz to 1 MHz 50 Hz to 1 MHz typical 200 ps 60 30 of actual for components from 1 MHz to 10 MHz Table 1 101 SDI Wander application Characteristic Supplemental information Wander Measurements Lo Measurements performed on SDI Ch A input signals only 149 Mbs 360 Mb s Drift Rate Accuracy 5 ppb s Table 1 102 SDI Interchannel Timing application Characteristic Performance requirement Supplemental information Digital to Digital Accuracy 1 sample Range 0 5 frame Digital to Analog Accuracy 400 ns Range 0 5 frame 1 40 VM700T Video Measurement Set Service Manual Specification Table 1 103 SDI Audio Video Timing application Characteristic Performance requirement Supplemental information Embedded Signal Accuracy 200 us Range 2 seconds less range on data streams heavily loaded with ancillary data External Signal Accuracy 200
115. 1 99 SDI Eye Diagram application cont Characteristic Performance requirement Supplemental information Full temperature range 10 for signals between 600 mVp p and 1 Vp p 20 to 80 Rise Time Accuracy 100 ps for rise times between 400 ps and 1 5 ns Signal Aberrations lt 5 for 800 mV step with 400 ps rise time Amplitude EI 10 mV tangential noise Timing es lt 100 ps tangential noise DC Offset Accuracy 10 mV 2 of reading from 1 V to 1 V Filter Performance EE 10 Hz filter 1 kHz filter oo 8dBattKz Table 1 100 SDI Jitter application Characteristic Supplemental information Jitter Measurements Measurements performed on SDI Ch A input signals only Maximum Amplitude 143 Mb s 3 ns pk to pk for frequencies of 0 5 MHz and above Max jitter ns 1500 jitter frequency kHz for frequencies below 0 5 MHz 270 Mb s 1 ns pk to pk for frequencies of 1 5 MHz and 1 2 ns pk to pk for frequencies of 1 25 MHz above and above typical Max jitter ns 1500 jitter frequency kHz Max jitter ns 1500 jitter frequency kHz for frequencies below 1 5 MHz for frequencies below 1 25 MHz typical 360 Mb s 0 9 ns pk to pk typical frequencies of 1 33 MHz and above Max jitter ns 1200 jitter frequency kHz for frequencies below 1 33 MHz Frequency Response of Jitter Waveform and Spectrum displays 143 Mb s 3 dB to 0 5 MHz 3 dB to 5 dB at 3 MHz VM700T Video Measurement Set Service Manual
116. 10 dB is set with the Noise soft keys The number of averages up to 256 is set with the Average Num soft keys Support Functions The third row down in the keypad contains support functions Menu Help Configure Function and Copy Turn any of these functions on by pressing the associated front panel button Of these Copy turns off either after the copy is sent or after pressing the Cancel soft key that appears in the Configure menu when a copy is pending Help is turned off by pressing the Help button a second time The remaining functions are turned off either by pressing the button a second time or by selecting a different operational mode in the top row Menu Button The Menu button displays a menu of soft keys across the bottom of the touch screen In some cases touching a soft key displays a further submenu of soft keys VM700T Video Measurement Set Service Manual 2 13 Operating Information Control Knob Help Button Pressing the Help button activates the Help function While Help is activated pressing a button or selecting a soft key displays a brief explanation of that button or soft key s function When the Help function is active all buttons and soft keys except Help lose their normal function and the LED on the Help button flashes Pressing the Help button a second time turns off the Help function Configure Button Configure accesses the Configuration files used to control the operation of the measurement set Yo
117. 10046 color bars signal q Check that the readout text in the upper right corner of the display reads 270 Mb r Touch the Horz Pos 270 Mbit soft key s Turn the front panel knob to center the left zero crossing of the Eye Diagram at approximately 0 15 UI 0 5 ns on the horizontal scale See Figure 5 13 VM700T Video Measurement Set Service Manual 5 29 Adjustment Procedure mv Eye Diagram F2 L97 scanning 270Mb 525 line Auto detect a BIRD SRS RECESS 300 pe in i ic ge E ul f amp fF 100 Wi f uH amp f 0 E Ei 6b A Adjust eye crossing to 0 15 UI f 200 FX 300 A fi E ld ER ME UE RU REL RE 0 2 0 0 0 2 0 4 0 6 0 8 Unit Intervals Filter 1 Khz Rise Fall Adjusted on DC OffsetiO0 5 mv Cable Len Bel 8281 22 meters Mode Waveform Measure Cursors Rescale Eye Units 2 Figure 5 13 Adjusting the eye crossing horizontal position t Touch the Horz Pos 270 Mbit soft key to save the adjustment A wait message will appear u Replace the 270 Mb signal on the SDI Ch A input with a 525 line 360 Mb television signal Check that the readout text in the upper right corner of the display reads 360 Mb w Touch the Horz Pos 360 Mbit soft key X Turn the front panel knob to the left eye crossing to approximately 0 15 UI 0 4
118. 105 Figure 6 67 Signal connections for performing Option 1S diagnostic 6 105 Figure 9 1 VM700T Video Measurement Set simplified block diagram EO pa e Rai Se ERU Se ag E 9 3 Figure 9 2 VM700T Video Measurement Set interconnection diagram 420 Vea es ER GC EO AKTE MM YO TCR 9 4 Figure 10 1 Front assemblies and power supply 10 15 Figure 10 2 Circuit boards 10 17 Figure 10 3 Chassis assembly 10 19 Figure 10 4 Cabinet and accessories 10 21 Figure 10 5 Option 1S circuit boards 10 23 Figure 10 6 Circuit board fuse locations 10 25 VM700T Video Measurement Set Service Manual Table of Contents List of Tables Table 1 1 Input characteristics Table 1 2 Digitizer Table 1 3 Synchronization Table 1 4 Physical characteristics Table 1 5 Power requirements Table 1 6 Environmental specification Table 1 7 Certifications and compliances Table 1 8 Safety standards Table 1 9 Safety certification compliance Table 1 10 Rear panel signal connectors Table 1 1
119. 2 dB at levels of 50 dBu and greater VM700T Video Measurement Set Service Manual 1 33 Specification Audio Spectrum Specifications Table 1 89 General Audio Spectrum specifications Specification Description Normal Res mode High Res mode Display bandwidth DC to 24 kHz Any 3 kHz within the display bandwidth Cursor readout accuracy Frequency 24 Hz 3 Hz Amplitude 0 5 dB 1 0 dB 0 5 dB 1 0 dB Frequency range for noise level 188 Hz to 20 kHz Selected 3 kHz window within the range of measurement 24 Hz to 24 kHz Signal Noise ratio 85 dB at full scale gt 70 dB for inputs gt 20 dBu with appropriate range selection Table 1 90 Audio Spectrum Level measurement specifications 188 Hz 20 kHz z 20 dBu 0 1 dB 20 dBu to 50 dBu 0 1 dB 50 dBu to 60 dBu 0 1 dB 60 dBu to 70 dBu 0 1 dB Table 1 91 Harmonic Analyzer measurement specifications measured Description Comments Highest Fundamental Frequency Harmonics up to the 20 kHz measurement bandwidth are displayed Measurement Update Rate View Harmonic Measurement Window All signal energy within the view window is 1 34 VM700T Video Measurement Set Service Manual Specification Table 1 92 Miscellaneous specifications Description Specification Channel separation crosstalk gt 100 dB 20 Hz to 20 kHz Input connectors Option 40 Two mini XLR Switchcraft TY3F requires Switchcraft TA3M mini XLR plug Two mini XLR to X
120. 21 671 3770 00 B010100 B010108 1 CKT BD ASSY ANALOG INPUT A1 80009 671 3770 00 671 3770 01 B010109 1 CKT BD ASSY ANALOG INPUT A1 80009 671 3770 01 22 211 0658 00 2 SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ 93907 821 12790 024 23 211 0661 00 8 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 24 174 1165 00 2 CABLE ASSY RF 75 OHM COAX 7 5 L 9M860 ORDER BY DESC 25 174 0843 01 1 ASSY RF COAX RFD 750HM RG174 RTANG SMB 2469 174 0843 01 26 672 1460 01 B010100 B010859 1 CKT BD ASSY GENLOCK A2 80009 672 1460 01 672 1460 02 B010860 B030531 1 CKT BD ASSY GENLOCK A2 80009 672 1460 02 672 1460 03 B030532 1 CKT BD ASSY GENLOCK A2 80009 672 1460 03 27 Not used 28 211 0661 00 7 SCR ASSEM WSHR 4 40 X 0 25 PNH STL POZ TK0435 ORDER BY DESC 29 Not used 30 343 1331 02 1 HOLDER PCB CIRCUIT BOARD RETAINER RIGHT 5Y400 343 1331 02 31 211 0507 00 2 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 32 Not used VM700T Video Measurement Set Service Manual 10 7 Replaceable Mechanical Parts Replaceable parts list cont Fig amp index Tektronix Serial no Serial no number effective discontd Qty amp description Mfr code part number 33 671 3922 01 B010100 B010212 1 CKT BD ASSY ACQUISITION MEMORY A18 80009 671 3922 01 671 3773 00 B010213 B019999 1 CKT BD ASSY ACQUISITION MEMORY A18 80009 671 3773 00 671 4108 00 B020100 B020230 1 CKT BD ASSY ACQUISITION MEMORY A18
121. 27 volts in 10 mV steps This offset is summed with the video signal to keep the signal centered in the dynamic range of the analog to digital converter ADC The video signal with offset applied is buffered by the offset amplifier and passed to the variable gain amplifier Variable Gain Amplifier variable gain amplifier consists of a resistive divider range switch followed by an amplifier with continuously variable voltage controlled gain The control voltage comes from a 12 bit DAC whose input code comes from a look up table contained in a programmable logic device Outputs from the look up table also control the range switch The input to the look up table is the five bit gain control word from the acquisition controller board Together these components provide a gain range of 0 to 7 75 in steps of 0 25 Dither Generator and Dither data bits from the acquisition controller board can be converted to 64 Dither Amplifier analog levels usually only the first 32 levels are used to effectively increase the resolution of the 10 bit ADC The dither amplifier buffers the processed video signal before passing it to the ADC board where it is digitized Calibration DAC The calibration DAC is a precision digital to analog converter used for gain compensation over the analog signal path including the analog to digital converter A calibration switch on each input channel couples the calibration signal onto the signal path at regular intervals The
122. 34 32 AWG 10 0 L 2X17 0 05X0 1CTR RCPT CTR PLZ BOTH ENDS CA ASSY SP RIBBON HDI 60 30AWG 10 7 L 2X80 CTR PLZ 0 5X0 1CTR BOTH ENDS OPTION BOARDS NOT SHOWN CKT BD ASSY AUDIO PROCESSOR A12 CKT BD ASSY AUDIO ANALOG A13 CKT BD ASSY TRIPLE INPUTAUDIO ANALOG A17 CKT BD ASSY INPUT SELECTOR A17A2 CKT BD ASSY GPIB A19 VM700T Video Measurement Set Service Manual Mfr code 05791 73743 93907 TK1547 TK1547 80009 80009 80009 80009 Mfr part number A 6941 0440 1 375 22 12157 50 ORDER BY DESC 174 3657 00 174 3616 00 671 1787 05 671 1788 05 672 1348 06 671 2337 00 10 9 Replaceable Mechanical Parts Replaceable parts list Fig amp index Tektronix Serial no Serial no number partnumber effective discontd Qty amp description Mfr code Mfr part number 10 3 0 441 2113 00 010100 019999 1 CHASSIS ASSY VM700T 80009 441 2113 00 441 2113 01 020100 CHASSIS ASSY VM700T 80009 441 2113 01 1 407 3649 00 B010100 B019999 1 BRKT MTG CRT VM700T 0J260 407 3649 00 407 3649 01 020100 1 BRKT MTG CRT VM700T TK1943 407 3649 01 2 212 0040 00 2 SCREW MACHINE 8 32 X 0 375 FLH STL POZ TK0435 ORDER BY DESC 3 211 0507 00 3 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 4 426 1629 04 1 FRAME CABINET OPEN FR 8 75 FULL RACK 80009 426 1629 04 5 213 0760 00 4 SCREW TPG TF 8 32 X 0 875 SPCL TAPTITE T20 93907 ORDER BY DESC 6 426 2204 00 1 FRAME SECT CAB BOTTOM LEFT 0
123. 39 Tektronix part number 331 0508 06 331 0508 07 211 0517 00 210 0055 00 210 0802 00 Not used 378 0322 00 354 0691 01 378 0323 00 354 0691 01 378 0325 00 354 0691 01 378 0324 00 354 0691 01 333 3521 00 671 0111 00 210 0405 00 210 0001 00 174 1163 01 672 1299 08 672 1299 09 212 0040 00 366 2159 01 333 4215 00 211 0658 00 211 0658 00 407 4289 00 337 3662 00 657 0098 03 657 0099 03 Not used 440 3786 01 119 6974 00 213 1014 00 210 1454 00 210 1456 00 348 0085 00 337 3448 00 211 0507 00 220 0625 00 671 1922 02 Serial no effective B050100 B010100 B010140 B050100 Serial no discont d B049999 B010139 B049999 Qty Name amp description 00 Ne xc DH O SCALE CRT FRAME FRONT FINISHED SCALE CRT FRAME FRONT FINISHED SCREW MACHINE 6 32 X 1 0 PNH STL POZ WASHER LOCK 6 SPLIT 0 031 THK STL WASHER FLAT 0 15 ID X 0 312 OD X 0 032 STL FILTER AIR FOAM 1 O RING 0 196 OD X 0 070 ID ETHYLENE PROPYL FILTER AIR FOAM 2 O RING 0 196 OD X 0 070 ID ETHYLENE PROPYL FILTER AIR FOAM 4 O RING 0 196 OD X 0 070 ID ETHYLENE PROPYL FILTER AIR FOAM 3 O RING 0 196 OD X 0 070 ID ETHYLENE PROPYL PANEL FRONT ON OFF CKT BD ASSY ON OFF A16 NUT PLAIN HEX 2 56 X 0 188 BRS CD PL WASHER LOCK 2 INTL 0 013 THK STL CD PL CA ASSY SP ELEC 5 26 AWG 7 7 L RIBBON CKT BD ASSY FRONT PANEL A10 CKT BD ASSY FRON
124. 4 If the amplitude is in tolerance skip to step 8 If it isn t turn off Averaging so you can see response changes Adjust C57 Mid Frequency on the ADC board to bring the flatness at 4 43 MHz into specification approximately 0 02 or less difference when compared to the 50 kHz reference 8 Set the leveled sine wave generator for 5 8 MHz but do not change the output level setting 9 If Averaging is on speed up the response to the frequency change by toggling the Average hard key off then back on again after the display has re stabilized 10 Check that the amplitude is within 0 55 of the reference level stored in step 4 If it is in tolerance skip to step 11 If the amplitude is out of tolerance you can try the adjustment of step 7 again to set the amount of change Delta Amp to the positive side of the tolerance that is nearer the 0 02 limit as a compromise You may also need to start the procedure all over again to re establish the reference level it may have drifted slightly from when you first acquired it You should next determine if the problem is only on one channel or on all channels If only one channel is involved the Analog Input board may need the flatness adjustments for the input channels done that procedure is described in the Extended Adjustment Procedure later in this section If all channels are involved the ADC board may need adjustment or repair part of the Analog Input board is also a sing
125. 465 10 ns div two input channels ence oscillator Adjusting the 18 MHz refer WWV 1 MHz ence oscillator Simulate 100 meters of Belden 8281 Adjusting the Cable Meter SC75A37B Cable Clone or cable 100 meters of Belden 8281 cable 75 Q impedance high quality noise Signal connections Tektronix part number free 1 meter length Adjusting the Cable Meter 012 0074 00 Adjusting the Cable Meter Tektronix part number 012 0074 00 75 Q high frequency 26 dB to 300 Tektronix part number MHz BNC connector 011 0163 00 Non metallic flat blade Adjust potentiometer Tektronix part number 003 1364 00 1 You can measure the jitter of your clock source using the SDI Eye Diagram application Select Free Run mode on Filter 10 Hz Average mode on and Average set to 4 The horizontal width of the rise and fall traces at the 0 mV level must be less than 150 ps as measured with the timing cursors 5 22 VM700T Video Measurement Set Service Manual Adjustment Procedure Preliminary Setup Prepare the equipment as listed below to perform the adjustment procedure 1 Remove the right side cover retaining screws on the VM700T as shown in Figure 5 10 Leave the side cover closed In some steps of the adjustment procedure you will slide the cover back to access internal components Connect the power cable to the VM700T and then power on the VM700T measurement set Watch the power up text to verify that the VM700T passes all diagnostics a
126. 48 kHz SELECT SELECT 0 10 20dB 0 10 20dB rowel P5 upply COM OPTO L R To Processor board for DAC and Control Clocks OPTO CLK To OPTO CONTROL Control Control Registers Relays OPTO DATA Figure 3 15 Audio Analog block diagram 3 38 VM700T Video Measurement Set Service Manual Theory of Operation 400 Hz Notch Filter DAC Output Notch Filter Operation DAC Output The signal enters on the left and is applied to the contact arm of a relay that switches the notch filter in or out of the Channel 2 signal path The filter is normally out When the relay is energized the 400 Hz notch filter is inserted in the signal path The notch filter circuitry has a bandpass filter at 400 Hz The output of the bandpass filter is combined with the input signal The gains are set 2 1 for a resulting output equal to the input signal minus the bandpass circuit output forming a notch at 400 Hz The output of notch filter goes to the A D converter The incoming signal current from the DAC is applied to the summing junction of a high speed operational amplifier This circuit converts the incoming current to a signal voltage and applies it to the CAL side of the NORM CAL relay Calibration Signals There are two calibration signal choices m The output of the DAC used during diagnostics m The output a high speed solid state switching device This device selects either ground
127. 5 MHz sampling mode VM700T Video Measurement Set Service Manual 3 7 Theory of Operation Ramp timeout pz Phase Locked Loop cem RTO li e Video Sync GENES Composite Sync Correction Stripper Syne Lock oH in 20 25 MHz clock Clock Mascus E FH Generator 1 Out Sync sync or Syne wey Phase indow aa a A Mode jue Mode Comparator O esr 182 227 4FSC Sync Mode L Video Std Main Mode Frame Mode Sound in Sync Composite sync Frame mode control CPU Bus Frame Decoder Frame Ref Clock approx 2 3 MHz Too High Lock Status Status Locke Coarse ie Low Correction i Decoded Frame Pulse 4FSC r Output Generator 4FSC Sync or Async Mode Sync or Async Mode b y Deglitcher Sample 20 25 MHz Mode Cloc 20 25 MHz Out Clock Frame Rate Synthesizer a Decoded 1 rame NAR Decoded Frame Pulse Frame Mode m i ising Edge Lf ZH Synthesized Frame Pulse Detect crame Synthesized E 105 125 Frame Mode E FH Clock Sync window Synthesized Synchronous Frame Mode F Mode Rising Edge Line Composite Sync Detect Pulse
128. 54 F hr max gradient 20 to 8096 relative humidity non condensing Max wet bulb temperature 29 4 C or 84 9 F derates relative humidity to 46 at 40 C or 104 F 8 to 80 relative humidity non condensing Max wet bulb temperature 40 C or 104 F derates relative humidity to 54 at 50 C or 122 F 2000 meters maximum Up to 40 000 ft 12 190 m Tektronix Class 5 Random Vibration Non operating Test For Laboratory Benchtop Instruments 10 minutes of vibration in each of the 3 major axes including the following levels 0 0175 g2 Hz from 5 to 100 Hz 3 dB octave from 100 to 200 Hz 0 00875 g2 Hz from 200 to 350 Hz 3 dB octave from 350 to 500 Hz 0 006132 at 500 Hz Overall level of 2 28 GRMS Tektronix Class 5 Random Vibration Operating Test For Laboratory Benchtop Instruments instrument meets performance specifications at these levels 10 minutes of vibration in each of the 3 major axes including the following levels 0 00015 g2 Hz from 5 to 350 Hz 3 dB octave from 350 to 500 HZ 0 000105 g2 Hz at 500 Hz Overall level of 0 27 GRMS Tektronix Class 5 Shock Test 16 drops 4 axes 30 Grms 11mS half sine wave 1 See the VM700T Environmental Characteristics in Table 1 6 for the operating temperature range of the VM700T operating without the Power Line Conditioner box inline VM700T Video Measurement Set Service Manual Specification PAL Measurement Specifications Measure Mode T
129. 59 5014 00 FUSE 2 0A 125V FAST BLOW 0 1 X 0 1 X 0 24 UL CSA 75915 R451 002 6 4 159 5014 00 FUSE 2 0A 125V FAST BLOW 0 1 X 0 1 X 0 24 UL CSA 75915 R451 002 6 5 159 5011 00 FUSE THRM CHIP SELF RESETTING FUSE 1 25A 06090 SMD125 2 HOLD 2 5A TRIP AT 20 DWG C 15V MAX 6 6 159 0193 00 FUSE WIRE LEAD 10A 60V FAST BLOW 5 SEC 61857 SP5 10A 6 7 159 0145 00 FUSE WIRE LEAD 15A 32V 10 SECONDS 61857 SP7 15A 6 8 159 0145 00 FUSE WIRE LEAD 15A 32V 10 SECONDS 61857 SP7 15A 6 9 159 5011 00 FUSE THRM CHIP SELF RESETTING FUSE 1 25A 06090 SMD125 2 HOLD 2 5A TRIP AT 20 DWG C 15V MAX 6 10 159 5011 00 FUSE THRM CHIP SELF RESETTING FUSE 1 25A 06090 SMD125 2 HOLD 2 5A TRIP AT 20 DWG C 15V MAX 6 11 159 5021 00 FUSE 15A 125V FAST BLOW 0 1 X 0 1 X 75915 R451 015 0 24 UL CSAR451 015 6 12 159 5010 00 FUSE SMD 7A 125V FAST BLOW 0 1 X 0 1X 75915 451007 0 24 UL CSA 6 13 159 0145 00 FUSE WIRE LEAD 15A 32V 10 SECONDS 61857 SP7 15A 6 14 159 0059 00 FUSE WIRE LEAD 5A 125V 61857 SPI 5A 6 15 159 0193 00 FUSE WIRE LEAD 10A 60V FAST BLOW 5 SEC 61857 SP5 10A 6 16 159 0194 00 FUSE WIRE LEAD 5A 125V 0 125 SEC 61857 SP5 5A LEAD TAPE REEL 6 17 159 0205 00 FUSE WIRE LEAD 1A 125V 5 SEC 61857 SP7 1A 6 18 159 0208 00 FUSE WIRE LEAD 2A 125V 5 SEC 61857 SP5 2A 6 19 159 5011 00 FUSE THRM CHIP SELF RESETTING FUSE 1 25A 06090 SMD125 2 HOLD 2 5A TRIP AT 20 DWG C 15V MAX 6 20 159 5011 00 FUSE THRM CHIP SELF RESETTING FUSE 1 25A 06090 SMD125 2 HOLD 2 5A TRIP AT 20 DWG C 15V MAX 10 14 VM7
130. 70 Figure 6 48 Set diagnostics power up mode menu 6 71 Figure 6 49 Instrument run modes menu 6 72 Figure 6 50 Normal Boot switch setting 6 73 Figure 6 51 High level diagnostics 6 74 Figure 6 52 Select run mode the high level diagnostic initial menu 6 75 Figure 6 53 Interactive run mode menu after running first main oes x ER VR CON QU MUS De aeg alo QU ne 6 77 Figure 6 54 Power up diagnostics selection display 6 78 Figure 6 55 High level diagnostics test blocks 6 79 Figure 6 56 Instrument Run Modes menu 6 85 Figure 6 57 Boot switch setting to enable diagnostic output to Serial port Ov jis ie isa EY DER EVE er RAV Vae ts 6 86 Figure 6 58 Diagnostics Configuration menu 6 86 Figure 6 59 VM700T rear 6 87 Figure 6 60 Front panel power supply and over temperature IndiCcators ieci wv o verdes cs EE EU CHE UE P TU 6 90 Figure 6 61 Power supply LED indicators 6 91 Figure 6 62 Power supply test points 6 93 Figure 6 63 Procedure for troubleshooting the audio option boards 6 95 Figure 6 64 Test positions on the Audio Analog board 6 96 Figure 6 65 SDI board cable connections and J5 pinouts 6 102 Figure 6 66 Option 1S simplified block diagram 6
131. 9 Washington Street Melrose MA 02176 FAX 781 665 0780 TestEquipmentDepot com
132. A1 Replacing the Analog Input Board VM700T displays the Faulty genlock board 2 Replace the genlock board Refer to Removing and re initializing message or Replacing the Genlock Board hangs Faulty ADC board A3 Replace the ADC board Refer to Removing and Replacing the ADC Board Faulty acquisition memory Replace the acquisition memory board Refer to A18 Removing and Replacing the Acquisition Memory Board Faulty Flash SIMM onthe Replace the Flash SIMM on the CPU board This will CPU board require a complete reprogramming of the CPU board Faulty memory on the Replace the memory SIMM on the CPU board CPU board Faulty CRT touch panel Replace the CRT touch panel Refer to Removing and Replacing the CRT Touch Panel Faulty front panel A10A1 Replace front panel keypad board assembly Refer to or keypad board A10A2 Removing and Replacing the Keypad Board 6 52 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Table 6 3 VM700T symptoms and corrective actions cont Symptom Possible cause Corrective action CRT touch panel not oper Touch panel out of calibra Try to calibrate the touch panel ating tion Faulty CRT touch panel or Replace the CRT touch panel Refer to Removing and cabling Replacing the CRT Touch Panel Loose connections Check connections on back of front panel board Refer to Removing and Replacing the CRT Touch Panel Faulty front panel A10A1 R
133. Apply a signal between 20 dBu and 30 dBu from a sine wave generator to the VM700T Audio Option See to Figure 4 9 for connec tions b Run the Audio Analyzer measurement and verify that residual THD N is 0 03 or less An applied signal of 8 to 10 dBu yields an optimal reading while a 20 dBu signal yields a worst case reading 2 Check THD N Measurement Accuracy a With 600 output resistance selected connect the outputs of two sine wave generators in parallel to the left channel of the dual female XLR to DB 37 female adapter cable see Figure 4 9 A To Option 41 audio input connector b 5 5 Figure 4 9 Option 41 cable connections distortion measurement accuracy check b Set one sine wave generator for a 2 V rms output at 1 kHz 4 22 VM700T Video Measurement Set Service Manual Audio Option 41 Triple Input Verification Procedure c Set the second sine wave generator for a 0 02 V 20 mV rms at 3 kHz These two signals add across the termination resistance to produce a 1 kHz signal with a 1 third harmonic distortion d Run the Audio Analyzer measurement and check for a THD N reading of 0 9 to 1 1 e Move the generator signals to the right channel input and repeat step 2 part d 3 Repeat step 2 for channels B and C substitute the appropriate channel when channel A is called for Check Frequency and Phase Measurement Accuracy This procedure requires an acc
134. Connector Option 48 VGA Connector Parallel Printer Connector Remote Contact Closure Relay Alarm Maximum Current Maximum Voltage Control Logic CH A CH B CHC and Ext Sync Feed Through Connectors 1 8 Description DB 9 male connectors configured as RS 232C DTE ports to provide hardcopy output to serial printers and remote control Meets electrical specifications described in IEEE 488 for parallel GPIB connectors 15 pin D type Outputs VGA signals DB 25 female Centronics compatible connector and signals Contacts are not debounced 50 mA 30 VACnys or 30 VDC set GRLY 1 closes the relay set GRLY 0 opens the relay BNC 75 2 Termination required when not used as feed through signal path VM700T Video Measurement Set Service Manual Specification Table 1 11 Optional power cords Plug configuration Option number North America Standard 125 V 15A Plug NEMA 5 15P Europe A11 230 V United Kingdom 230 V North America 230 V Switzerland 230 V 1 European and United Kingdom power cord options A1 and A2 also require the VM700T power line conditioning box for operation in EU countries The power line conditioner prevents power spikes from the VM700T power supply from entering the commercial power mains VM700T Video Measurement Set Service Manual 1 9 Specification Power Line Conditioner for Option A1 and A2 Power Cords Table 1 12 AC Electrical Characteristics Characteristic Vol
135. Control ce dece et ee Re hae Res 3 40 Opto IsolatotS et e tr tee were bette ve get ev eT ee eb Rn es 3 40 Sy OCONEE pe NR MR TERM 3 41 Counter Decoder oun rt TH RR een s 3 41 Control RegisteE cues dem d etre D RR e RT Ue Se Rer n d 3 41 Master Oscillator and Clock Divider 3 41 Calibration DAC xt Ere tat ere pte d havea ed 3 42 Floating Power Supply 0 0 ec nen 3 42 te TENE Dee tata vate aed 3 42 Option 41 Audio Analog Board 3 42 6 Balanced Input Selector ee ee eee eee 3 42 Option 48 GPIB Interface Board A19 3 44 Option 1S Serial Digital 3 47 SDI Rear Panel Interface Assembly 3 47 SDDBoatd ted 3 47 Performance Verification Self Diagnostics uoc o Spach ete ton d ace Moe b Ds nee ace io Ad 4 1 Test Equipment Required ccc cee eee 4 6 System Verification Procedures 4 7 Audio Option Verification Procedure vus tyes uui ee m 4 13 Test Equipment Required risos oe rer he 4 13 Audio Option 40 Verification Procedure 4 15 Check Level Measurement Accuracy and Flatness 4 15 Specifications Checked ime i E eee ee 4 15 Option 40 Level Accuracy a
136. Decoded Async or 20 25 MHz Mode Frame Mode Figure 3 2 Genlock board A2 block diagram 3 8 VM700T Video Measurement Set Service Manual Theory of Operation FH Generator FH generator provides an NTSC or PAL line rate frequency reference clock to the phase locked loop using either the horizontal sync output from the sync stripper or the line rate frequency derived from the 20 25 MHz crystal clock The FH generator also provides a timing reference to the frame decoder Phase Locked Loop PLL PLL takes in a reference clock at the PAL or NTSC line rate frequency and outputs a frequency of 8 times the color subcarrier frequency 8Fsc The PLL is not used in 20 25 MHz sampling mode The phase comparator compares the reference clock to the output of the PLL feedback circuit and generates a correction voltage to keep the two synchronized The feedback circuit outputs a window centered on the leading edge of the reference clock If the reference clock falls outside the window the PLL is unlocked and the coarse correction circuitry activates to quickly bring the reference clock back into the window The loop filter smooths and integrates the correction voltage which is then used to drive the voltage controlled oscillators VCO Two VCO generate the 8Fsc clock one for PAL and the other for NTSC Control logic enables one VCO at a time The output of the selected VCO is divided to the line rate frequency and fed back
137. ECL data to single ended TTL data and stores it in the acquisition memory The data acquisition memory consists of static RAM accessible by the CPU during data acquisition the memory appears to be dual ported Besides converting ECL data to single ended TTL the controller portion of the board controls data acquisition patterns that handle the following analog processing hardware functions clamping input selection sync source filter selection offset gain dither and genlock VM700T Video Measurement Set Service Manual 3 1 Theory of Operation 3 2 The CPU board A5 contains a microprocessor a floating point unit real time clock Flash EPROM NVRAM display memory and display driver hardware The display driver hardware converts acquired data to video and drives the VM700T display A monochrome output to the rear panel is also derived from the display driver hardware The Flash EPROM stores application programs and the NVRAM stores system and configuration files created by the user The front panel interface hardware is also on the CPU board This interface controls the touch panel control knob and keyboard interfaces to the CPU microprocessor The audio option boards for Option 40 and 41 provide the interface for audio test signals into the VM700T Operation of the audio option measurements are discussed in VM700T Option 40 41 42 Audio Measurements User manual A second option requiring additional hardware is Optio
138. Fall Time 300 ns to 1 us 30 ns Line Sync 1 4 us to 6 6 us 10 ns 4 7 us nominal Sync to Start of Burst 2 2 us to 8 us 20 ns 5 6 us nominal Burst Duration 1 4 us to 3 us 25 ns SCH Phase 5 Table 1 39 Field Blanking timing measurements Equalizing Pulse Duration 1 4 us to 20 us 2 35 us nominal 10 ns Broad Pulse Separation 1 4 us to 20 us 4 7 us nominal 10 ns VM700T Video Measurement Set Service Manual 1 17 Specification Table 1 40 Other Timing measurements Measurement Bar Rise Time x20 ns B2 Measured from 1096 to 30 ns 9096 points 120 ns to 300 ns 0 3 us to 1 0 us Table 1 41 Amplitude and Phase measurements Measurement Average Picture Level Sync Amplitude Error Sync Amplitude Error with Sound in Sync Burst Amplitude Error Chrominance Reference Amplitude Error Luminance Bar Amplitude Error Luminance Bar Amplitude Luminance Bar Amplitude 96 of carrier Residual Carrier Bar Top Blanking Level Chrominance Luminance Gain Inequality Chrominance Luminance Delay Inequality Sync Bar Rel 3 7 Sync to Bar Top C L Gn Err using modulated Pulse Sync Amplitude Burst Amplitude Burst Amplitude Difference 100 to 50 0 3 300 mV nominal of nominal 100 to 50 0 3 Last broad pulse in field CCIR Rec 569 300 mV nominal of nominal 80 to 50 1 0 Live picture area CCIR Rec 569 300 mV nominal 80 to 50 1 0 D2 CCIR Rec 569 30
139. IB processor In normal operation when the VM700T processor request access the Dual Port RAM controller grants it access However as long as both processors are making accesses they will be alternated so that the GPIB processor is not blocked During normal operation communications between the two processors take place through the shared RAM and the IPC register The IPC register allow either processor to set an interrupt flag to the other processor When an interrupt occurs the inter processor communication is written to buffer then the other processor is interrupted to let it know a message is ready When the interrupt has finished the interrupted processor accesses the data to complete the communica tion A second type of access occurs in the debug mode There is a debug window that allows the VM700T processor to see all 16 Mbytes of the 24 bit addresses of the GPIB processor Access by the VM700T processor through the debug window halts the GPIB processor The GPIB processor relinquishes control of its address bus and the VM700T processor takes control The GPIB processor memory decoding circuitry is used by the VM700T processor to see the address space so the debug window can be used to test most of the GPIB hardware An exception to this is the GPIB processor interrupts The VM700T processor has no means to see or handle interrupts to the GPIB processor LED status indicators for are on the rear panel of the GPIB interface board The
140. ICS INTERFACE will revert to its factory default settings and ERROR LOGGING will be disabled until instrument power is cycled or the instrument is otherwise reset Press MENU BUTTON to clear NVRAM any other button to abort Figure 6 43 Clear CPU NVRAM Utility menu Calibrating the Touch VM700T is shipped from the factory with its touch screen fully calibrated Screen Although it will seldom be necessary the touch screen can easily be recalibrated To calibrate the touch screen 1 Switch off power to the VM700T at the front panel 2 Press and hold the Menu button while turning on the power After the VM700T beeps twice to acknowledge the startup mode release the Menu button The VM700T then initializes directly into the Low Level Diagnos tics Interface with the VM700T startup menu as shown in Figure 6 40 on page 6 66 3 Inthe startup menu use the large control knob to highlight the T in the Calibrate Touch Panel Interface line 6 68 VM700T Video Measurement Set Service Manual Troubleshooting Procedures 4 Press the Select Line button to make the selection to calibrate The first touch screen calibration instructions are then displayed as shown in Figure 6 44 5 Follow the written directions You can press AUTO to abort the calibration process and returns to the VM700T startup menu Press any other button to store the setting in NVRAM and brings up the next touch screen calibration menu 6 Afte
141. J7N4 426 2204 00 7 211 0507 00 1 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 8 426 2203 00 1 FRAME SECT CAB BOTTOM RIGHT 0J7N4 426 2203 00 9 211 0507 00 3 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 10 426 2202 00 2 FRAME SECT CAB TOP RIGHT LEFT 0J7N4 426 2202 00 11 211 0507 00 7 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 12 124 0430 00 4 STRIP TRIM CORNER W STEP 20 0 61153 124 0430 00 13 348 0632 00 4 SHLD GSKT ELEK FINGER TYPE 19 0L CNR LEFT 80009 348 0632 00 14 348 0633 00 4 SHLD GSKT ELEK FINGER TYPE 19 0 L CNR RIGHT 80009 348 0633 00 15 343 1070 00 8 RTNR ELEK SHLD STAINLESS STEEL 0J7N4 343 1070 00 16 386 6950 00 1 PANEL REAR REAR PANEL 0 100 ALUM TK1943 386695000 17 211 0507 00 11 SCREW MACHINE 6 32 X 0 312 PNH STL POZ TK0435 ORDER BY DESC 17a 211 0504 00 2 SCREW MACHINE 6 32 X 0 250 PNH STL POZ TK0435 ORDER BY DESC 18 213 0808 00 4 SCREW TPG TR 8 32 X 0 625 L TAPTITE STL POZ 93907 ORDER BY DESC 19 200 2222 00 B010100 B029999 1 GUARD FAN 7912AD 81041 6 182 033 20 119 2616 02 1 FAN 24VDC 28A 6 7W W LEADS 17 0L 0J260 119 2616 02 21 212 0010 00 4 SCREW MACHINE 8 32 X 0 625 PNH STL POZ TK0435 ORDER BY DESC 22 210 0458 00 4 NUT PL ASSEM WA 8 32 X 0 344 STL 73893 ORDER BY DESC 23 348 0014 00 4 FOOT CABINET BLACK PHENOLIC 0 25 ORDER BY DESC 24 212 0010 00 4 SCREW MACHINE 8 32 X 0 625 PNH STLPOZ TK0435 ORDER BY DESC 25 348 0276 01 6 SHLD GSKT ELEK MESH TYPE 0 124
142. Khz Rise Fall Adjusted on Mode Waveform Measure Cursors Rescale Eye Units 2 Figure 5 14 Adjusting the rising edge of the SDI Eye Diagram application 5 31 VM700T Video Measurement Set Service Manual Adjustment Procedure 5 32 NOTE The following step adjusts the 18 MHz reference oscillator by observing the slip rate between the oscillator and the 1 MHz WWV reference signal A slip rate of 10 ns per second results in a maximum error of 0 01 ppm 5 Perform the following step to adjust the 18 MHz reference oscillator a Slide back the right side cover to access the SDI board test point and adjustment resistor See Figure 5 12 on page 5 28 Connect the 1 MHz WWV reference signal to channel 1 of your oscilloscope Connect a probe from channel 2 of the oscilloscope to TP17 on the SDI board See Figure 5 12 on page 5 28 Set the oscilloscope as follows 10 ns div DC coupled channel 1 to 500 mV div and 1 MQ DC input channel 2 to 500 mV div and 50 Q DC input and triggered to channel 1 WWV Adjust R490 on the SDI board see Figure 5 12 on page 5 28 so that the channel 2 signal display on the oscilloscope is stationary maximum horizontal drift of less than 1 division per second Remove the probe from TP17 on the SDI board Slide the cover forward and install the side cover retaining screws See Figure 5 10 on page 5 23 Remove all cables and terminators from the VM700T VM700T V
143. LR female adapters and two mini XLR male plugs are supplied Option 41 One male DB 37 connector One DB 37 female connector is supplied Input impedance 50 kQ balanced differential 1 Noise limited source impedance for both channels is lt 600 Q Multitone Analyzer Specifications Table 1 93 Multitone Analyzer measurement specifications Description Specification Comments Level of Individual Tones Relative to Multitone RMS Level Multitone 1 Multitone 2 Multitone 3 Multitone 4 Reference Frequency for Multitone Recognition Multitone 1 Multitone 2 Multitone 3 Multitone 4 VM700T Video Measurement Set Service Manual 1 35 Specification Table 1 93 Multitone Analyzer measurement specifications cont Description Specification Comments Minimum Amplitude of Reference Tone for Multitone Recognition Input Range Window m U gt AUTO RANGE Minimum Multitone Recognition Time 1 second first time Measurement Update Rate After Recogni 5 readings per second tion Maximum Frequency Error for Multitone Within 10 of reference frequency Recognition Level Measurement Accuracy Same as Audio Analyzer Frequency Measurement Accuracy Same as Audio Analyzer AN Timing Specifications Option 42 Table 1 94 Audio Video Timing measurement specifications Characteristic Performance requirement Audio Amplitude Window 92 dB Audio Amplitude Range 102 dB to 30 dB in five ranges Timing Range 65 ms
144. LSTN TALK SREQ and CACT controller active bits are all derived from the various control and handshake lines coming from the GPIB controller Figure 3 19 shows the rear panel and status LED arrangement for the circuit board LSTN SREQ LOCK SYSCTL TALK REM CACT Figure 3 19 GPIB rear panel arrangement VM700T Video Measurement Set Service Manual Theory of Operation Option 1S Serial Digital Measurements Option 1S is composed of three boards the SDI Rear Panel Interface assembly the SDI board and a modified Acquisition Memory board SDI Rear Panel Interface SDI Rear Panel Interface assembly contains the low distortion loopthrough Assembly circuitry for both the SDI Channel A and the Analog Reference inputs For the other signal connectors the purpose of the assembly is to provide physical connections for the signals into the measurement set SDI Board The SDI board contains the analog and digital processing circuitry for the SDI applications The board s purpose is to perform a variety of conversions on the incoming signals so they can be acquired by the Acquisition Memory board The SDI Board is split between a digital signal path and an analog data path The circuit blocks of each data path shown in Figure 3 20 is discussed below Digital Signal Path The digital signal path is comprised of the following blocks as shown in Figure 3 20 Equalizer For SDI signals the equalizer active
145. Main Board Board CPU Diags Display Diags Diags Main Board Front Panel Interface Diags Overall Run Mode Power Up Auto Reset Custom Sequence Dm Mode Result Display Mode Result Logging Mode Build a Sequence CPU Diags Display Diags Front Panel Diags Test List Test List Diags Test List Test List Use Abort or press the Auto button to back up the tree to the VM700T Startup Menu Audio Diags GPIB Diags Test List Test List Figure 6 32 VM700T diagnostic menus overview cont 6 58 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Low Level Diagnostics Access to the diagnostics menu is available during power up by holding in the Menu front panel button in when the power is turned on Press and hold the Menu button while turning on the power After the VM700T beeps twice to acknowledge the startup mode release the Menu button The VM700T then initializes directly into the Low Level diagnostics mode The diagnostic operation begins with the Low Level Diagnostic Interface VM700T Startup Menu shown in Figure 6 33 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection VM700T STARTUP MENU Key Selection R Instrument RUN MODES Menu U UTILITIES Menu D Low Level DIAGNOSTICS Menu C Diagnostics CONFIGURATION Menu H Diagnostics HELP Menu T Calibrate TOUCH PANEL INTERFACE Reprin
146. OGRAM Instrument Show FIRMWARE Date Codes Show INSTRUMENT ID number Reset Software OPTION KEY or m Reprint Q Abort Menu Input your selection Figure 6 41 Diagnostic Utilities menu 6 66 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Clearing the CPU NVRAM and FILE SYSTEM NVRAM The diagnostic utilities include the NVRAM utilities These utilities have a couple of uses one is to recover after removing the CPU NVRAM or file system NVRAM plug in modules from the CPU board the other is to clear the file system of user files if the VM700T is being transferred to another user or work location The backup battery for the CPU NVRAM and file system NVRAM is on the CPU board If the memory SIMM is removed from the CPU board the stored memory is lost and the memory cells will be in random states Clearing the memory restores factory default settings for the file system and CPU so that the VM700T can be booted up Use the following procedure to clear the CPU NVRAM or the file system NVRAM 1 Access the Utilities menu following the procedure on the preceding page 2 From the Utilities menu see Figure 6 41 use the front panel knob to select N and then press the Select Line button This displays the NVRAM utilities menu with the following two choices F Clear FILE SYSTEM NVRAM C Clear CPU NVRAM 3 Use the front panel knob to select F to clear the file syst
147. OL DYNAMIC ADDRESS lt BUFFER Figure 3 8 Controller section block diagram VM700T Video Measurement Set Service Manual CONTROL gt SETTINGS STATIC RAM OUTPUT 2K X 32 DATA BUFFER 3 23 Theory of Operation Status Counter ECL To TTL Conversion Data and Address Latches 3 24 onto the BCDo 2 Bus Trigger RAM Sequencer State Machine A triple timer counter counts status pulses from the acquisition section of the board The status pulses may be used by applications to indicate events occurring in an acquisition pattern The differential ECL signals from the ADC board D0 D9 FRAME OUT LINE OUT CKD and OVERRANGE are converted to single ended TTL outputs before being used by the Acquisition Controller board A TTL to ECL conversion of OLS and PSR to ECL levels is also done These signals Sync Reset and Async Set control the modes of the ADC board so that it either outputs all ones or zeros or does conversion operations The data from the ADC board are latched into data latches and clocked out by to resynchronize the data to the clock signal Controller ASIC loads address latch with 10 bits of address Three additional bits BCD 3 15 are added from to complete the address Bits from the control register RUN and STOP can switch the trigger RAM input from data latch output normal operation to address latch output Switching the trigger RAM input to the outpu
148. ON SERIAL PRINTER 070 9630 XX 1 MANUAL TECH SERVICE MANUAL 80009 070 9630 XX POWER LINE CONDITIONER for use with Option A1 and A2 European Power Cord Options 075 0705 XX 1 KIT INSTRUCT EURO EMC POWER LINE COND TK2548 075 0705 00 119 6589 XX 1 FILTER ASSY PWR SPLY LINE FILTER ADAPTER 80009 119 6589 00 212 0518 00 4 SCREW MACHI 10 32 X 0 312 PNH STL CD PL POZ 93907 ORDER BY DESC 348 0430 00 4 BUMPER PLASTIC POLYURETHANE BLACK 2K262 ORDER BY DESC 407 4893 00 1 BRACKET ADAPTOR LINE COND BOX 0 050 AL TK1943 407 4893 00 10 12 VM700T Video Measurement Set Service Manual Replaceable Mechanical Parts Replaceable parts list Fig amp index Tektronix number part number 10 5 1 671 4136 00 671 4136 01 671 4136 02 671 4136 03 671 4136 04 2 174 3779 00 3 174 3850 00 4 174 3848 00 5 174 3891 00 6 174 3849 00 7 343 0549 00 8 672 1504 00 9 386 4247 00 10 211 0409 00 11 333 4247 00 12 159 5010 00 18 159 5011 00 Serial no effective B030100 B030210 B030412 B030850 B030920 B030100 B030100 B030100 B030100 B030100 B030100 B030100 B030100 B030100 B030100 B030100 B030100 Serial no discont d B030209 B030411 B030849 B030919 Name amp description BD ASSY SDI BD TESTED 389 2417 00 WIRED BD ASSY SDI BD TESTED 389 2417 00 WIRED BD ASSY SDI BD TESTED 389 2417 00 WIRED BD ASSY SDI BD TESTED 389 2417 00 WIRED CKT BD ASSY SDI BD TESTED 389 2417 00 WIRED
149. OVERTEMPERATURE ES Ol OVERCURRENT LS OV OVERVOLTS S UV UNDERVOLTS Red LED indicators Green LED indicators all off en normal all on n normal ooooeeeeoceo OV OT 15 5 2 5 412 415 Figure 6 61 Power supply LED indicators Check that the VH housekeeping supply LED indicator comes on see Figure 6 61 If it does not come on replace the power supply Refer to Power Supply Module on page 6 38 for power supply removal instructions Check the green LED indicators on the power supply Each voltage supply is provided with an indicator to show that the associated voltage is up All the green indicators should be on for normal operation of the power supply Check that none of the RED indicators are lit If any are on a power supply problem is indicated If the VH housekeeping voltage LED is on and the other green voltage indicators are flashing on and off check the status of the OI over current LED If the OI LED is flashing or on solid there may be excessive loading on the power supply by the VM700T circuitry See Table 6 9 for checks and actions for the various trouble indications VM700T Video Measurement Set Service Manual 6 91 Troubleshooting Procedures Table 6 9 Power supply trouble indicators Indicator Undervoltage LED on Over Voltage LED on Over Temperature LED on Over Current LED on 6 92 Check Supply LED indicators to check for a Replace power supply using board exchan
150. OWER SUPPLY FAIL LED lit For no display blank screen CRT display symptoms follow this procedure 1 Connect an external VGA monitor to the rear panel VGA connector If there is no display on the external monitor the problem may be in the CPU or display driver circuitry on the CPU board Exchange the CPU board with a known good one to see if the display returns If there is a VGA output display but none on the CRT continue with these checks 2 Make sure that 12 V is present on pin 7 of the CRT display connector on the back of the display module If 12 V is not present remove the 10 pin drive connector to see if the 12 V comes up If it does the CRT display may be loading the power supply Change to CRT display assembly and check again to see if the display returns 3 With an oscilloscope probe pins 6 horizontal sync 8 video and 9 vertical sync of the CRT display connector for valid drive signals 4 Adjust the brightness and contrast controls on the bottom of the CRT display unit to see if they affect the display For blank screen and lighted POWER SUPPLY FAIL LED symptoms follow this procedure 1 Switch the instrument power off at the rear panel switch 2 Disconnect the CRT 12 V power connector P3 at the power supply and switch instrument power on to see if the display monitor was loading the power supply If the POWER SUPPLY FAIL LED is no longer lit with the 12 V cable disconnected replace the CRT display mo
151. S es oe TS EEA AR REE ES 2 9 User Programmable Functions 2 10 Hardcopy rte ee mate rece oa eoe se s 2 10 Remote Operation i cesses eee DIR IRE ERR Er CD ERES LE 2 10 VM700T Video Measurement Set Service Manual i Table of Contents Eront Panel Controls snore sis et tee etu RR wre ees par a 2 11 SCIe en co sso etr wre nie epa e ute ets ove ein de aen ve pease 2 11 etre teet et eis ots ed ser e ete E 2 12 Control Knob codo Lo e e ERR wre eats SR Der Rn we geese 2 14 Equipment Signal Sources 2 15 Bandwidth ir ATE 2 15 Connecting Inputs and Outputs 2 15 Rear Panel and Connections cece eee eee 2 16 Equipment Video Signal Sources Required 2 18 Connecting Audio Option 40 toa Source 2 19 Input Connector Pin Assignments 2 19 Connecting Audio Option 41 toa Source 2 20 Option 41 Audio Signal Interconnection Cable 2 20 GPIB Option 48 Signal Connections and Rear Panel 2 21 GPIB Indicator EED rie onr tate ta e ee pete core e er Ro ena 2 21 SDI Option 1S Rear Panel 2 22 Theory of Operation Overview of The VM700T System
152. SC Measurement Specifications Measure Mode Table 1 47 Bar Line Time Measurement Bar Level Sync Level Sync to Bar Top Sync Bar Ratio Bar Tilt Rec 569 Line Time Distortion Rec 567 Bar Width Table 1 48 Bounce Measurement Peak Deviation Settling Time Table 1 49 Burst Frequency Measurement Burst Frequency Error This section lists the specifications for each NTSC measurement The accuracies shown for measurements with averaging capabilities assume the default averaging factor of 32 Test signals of known parameters are provided by characterized and traceable television signal generators to test the accuracy of these derived measurements Due to the statistical nature of digitizing measure ment methods reported results will meet these specifications 97 of the time Range specifies the extremes between which a measurement can be made All measurement accuracies specified are valid only with nominal inputs signals with an unweighted signal to noise ratio of at least 60 dB on the incoming signal and a termination accuracy of 0 025 Accuracies shown for measurements with relative mode accuracy assume that an averaging factor of 256 was used to create the reference An IRE is a voltage unit of measure and is equal to 1 140 of a volt or 7 14285 mv 100 IRE is 714 285 mV This value often rounded to 714 mV or with less rounding to 714 3 mV A 1 V pk pk signal is 140 IRE Relative mode accuracy 1096 to 12596 0 5
153. T PANEL A10 SCREW MACHINE 8 32 X 0 375 FLH STLPOZ KNOB TV GRAY SCROLL 1 243 ID X 1 4 OD X 0 42 H PANEL FRONT FRONT PANEL LEXAN SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ CKT BD ASSY KEY A10A2 FOR REPLACEMENT SEE A10 SCREW MACHINE 6 32 X 0 312 PNH STL POZ CKT BD ASSY FRONT PANEL A10A1 FOR REPLACEMENT SEE A10 SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ BRACKET KEY BD 407 3922 00 amp 337 3662 00 SHIELD ELEC 4 96 L BE CU CLIP ON RIGHT MODULAR SUBASSY W TOUCH PANEL A14 STD MODULAR SUBASSY W TOUCH PANEL OPT 74 PANEL CONDCT ETCHED CONVEX TYPE 0927 TOUCH PANEL SCREW TPG TF 10 16 X 0 5 HEX HD STL ZN PL WASHER FLAT WASHER SHLDR 0 5 DIA W 0 203 DIA ID GROMMET PLASTIC GRAY U SHAPE 0 48 ID SHIELD ELEC CRT SCREW MACHINE 6 32 X 0 312 PNH STL POZ NUT SHEET SPR 6 32 STLCLIP ON TYPE CKT BD ASSY DISPLAY A14A1A1 VM700T Video Measurement Set Service Manual Mfr code 0JR05 7X318 TK1907 86928 86928 85471 02697 85471 02697 85471 02697 85471 02697 0KB05 80009 73743 78189 9M860 80009 80009 TK0435 TK1163 0KB05 93907 TK0435 93907 80009 30817 80009 80009 80009 80009 3M099 5Y400 TK0588 0KBZ5 5Y400 TK0435 78553 80009 Mfr part number 331 0508 06 ORDER BY DESC 211 0517 00 ORDER BY DESC ORDER BY DESC 378 0322 00 2 004 E803 70 378 0323 00 2 004 E803 70 378 0325 00 2 004 E803 70 378 0324 00 2 004 E803 70 ORDER BY DESC 671 0111 00 12157 50 1202 00 00 0541C 174 1163 01 672 1299 08
154. TC7 combination signal Leave the SDI Ch A input terminated with the high frequency terminator Adjust the digital television signal generator for a jitter frequency of 3 MHz and a jitter amplitude of 1 ns on the signal output Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 3 MHz as read in the readout Check that the Spectrum Cursor 1 amplitude readout is 14 to 22 dB Check that the Timing p p readout is 700 to 1400 ps Check that the Alignment p p readout is 700 to 1400 ps 8 Perform the following steps to check the Jitter application at 360 Mb and 15 kHz a c d Replace the 143 Mb signal on the SDI Ch A input with a 360 Mb 525 line 10 step signal Leave the SDI Ch A input terminated with the high frequency terminator Adjust the digital television signal generator for a jitter frequency of 15 kHz and a jitter amplitude of 2 ns on the signal output Check that the Timing p p readout is 1600 to 2600 ps Check that the Alignment p p readout is 1600 to 2600 ps 9 Perform the following steps to check the Jitter application at 360 Mb and 9 9 MHz a Adjust the digital television signal generator for a jitter frequency of 9 9 MHz and a jitter amplitude of 0 7 ns on the signal output Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 9 9 MHz as read in the readout Check that the Spectrum Cursor 1 amplitude
155. Test Equipment Depot Service Manual 1 800 517 8431 Tektronix VM700T Video Measurement Set 070 9630 05 Test Equipment Depot 800 517 8431 99 Washington Street Melrose MA 02176 FAX 781 665 0780 TestEquipmentDepot com Table of Contents Specification Operating Information General Safety Summary xv Service Safety Summary 0 0 cece cece eee tenn eee E Contents ofthe Manual eee eee eens Electrical Characteristics 1 1 Physical Characteristics assores sereine cece eee ee 1 4 Power Requirements eens 1 4 Environmental xp ET EELE ENRIQUE Ie dee BRL dE uus 1 4 Power Line Conditioner for Option A1 and A2 Power Cords 1 10 PAL Measurement Specifications 1 12 Measure Mode olei DES DUI VER Pe ERRARE DR refs 1 12 AUTO MOG RR eco Gath as cain veas Lee Calan ah 1 17 NTSC Measurement Specifications 1 21 Measure Mode ioco EL ier VE SUD CER eR RR NP Vers 1 21 Auto Mode i vbi tua PRESE Vb eV AG AG Ede veros 1 26 Audio Option 40 Option 41 and Option 42 Specifications 1 31 Automatic Audio Test 1 31 Audio Analyzer
156. The following tables give the specifications for the audio measurements Automatic Audio Test Specifications Table 1 85 0 33 Automatic audio test measurement specifications Measurement Accuracy includes flatness Insertion Gain Error 0 2 dB Sweep Gain Min and Max 20 1 dB THD N at 1020 Hz 10 1 digit 2nd Harmonic at 60 Hz 10 1 digit 3rd Harmonic at 60 Hz 0 03 to 70 10 1 digit Crosstalk into channel 1dB Test Level 6 dBu lt 66 dB to 0 dB 0 dBu lt 60 dB to 0 dB 6 dBu lt 54 dB to 0 dB SNR unweighted 4 1 dB Test Level 6 dBu 10 dB to 2 76 dB 0 dBu 10 dB to 2 70 dB 6 dBu 10 dB to 2 64 dB SNR weighted 5 2 dB Test Level 6 dBu 10 dB to 76 dB 0 dBu 10 dB to 70 dB 6 dBu 10 dB to 64 dB Max Compandor Error rise fall 0 2 dB Gain Difference 12 dB 0 2 dB Phase Difference 180 to 180 1 1 Assumes insertion gain is within 6 dB 2 The measurement range specification assumes that the input level is within 6 dB of the 0 33 test level the audio configuration The actual 0 33 test level range is 6 dBu to 14 dBu 3 The value for other test levels can be calculated from the formula 60 Test Level Measured with Quasi Peak response as per CCIR 468 4 recommendation The measurement range can be determined from the formula 70 Test Level 5 Weighting filter as per CCIR 468 4 recommendation VM700T Video Measurement Set Service Manual 1 31 T
157. Triple Input Audio input connector pin locations Installing the EMI Reduction Ferrite Choke The EMI reduction parts consist of two ferrite forms and two cable tie wraps to secure the ferrite forms on a multicon ductor cable The ferrite forms fit together on a cable that has an outside diameter of 0 5 inch or less The ferrite choke consists of the following parts Ferrite forms 2 ea Tektronix part number 276 0832 00 m Cable tie wraps 2 ea Tektronix part number 346 0120 00 When installed as described on the assembled audio cable the ferrite forms act as a choke to reduce the level of high frequency noise emitted from the signal interconnection cabling VM700T Video Measurement Set Service Manual 6 13 Maintenance Option 48 GPIB Interface Board Removal and Replacement Perform the following steps to install the ferrite choke after assembling the cable to the supplied connector 1 Place a cable tie wrap around the cable with the tie wrap end started through the tie binder to form a loop 2 Place both ferrite forms on the cable as shown in Figure 6 8 The parts must be placed as close to the to the connector as possible 3 Slide the loop of the tie wrap over the two ferrite halves and tighten the tie wrap firmly Trim off the excess end of the tie wrap 4 Place an additional tie wrap around the cable behind the ferrite forms to eliminate the possibility of the assembled parts slipping on the cable Tighten the
158. U O 0 187 DIA SFT WASHER FLAT 0 19 ID X 0 438 OD X 0 031 POLTHN SL SECT DWR EXT 12 625 L W O HARDWARE NUT PL ASSEM WA 8 32 X 0 344 STL RACK MOUNT SIDE COVER SLIDE DWR EXT 20 0 X 1 69 PAIR R amp L 15 INTER CABINET TOP PORTABLE SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ CAB SIDE ASSY RIGHT PORTABLE CAB SIDE ASSY RIGHT PORTABLE SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ CABINET SIDE LEFT PORTABLE W HANDLE CABINET SIDE LEFT PORTABLE W HANDLE SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ CABINET ASSY BOTTOM PORTABLE CABINET ASSY BOTTOM PORTABLE SCR ASSEM WSHR 6 32 X 0 312 PNH STL POZ CABINET ASSY BOTTOM PORTABLE FOOT CABINET BOTTOM BLACK POLYCARBONATE SCREW MACHINE 6 32 X 0 312 FLH 100 DEG PAD CAB FOOT 0 69 X 0 255 X 0 06 PU COVER PROT 17 164 X 9 0 PLASTIC CA ASSY PWR 3 18 AWG 250V 10A 98 INCH STR IEC320 RCPT X NEMA 5 15P US TERMN COAXIAL 75 OHM BNC Mfr code 5Y400 5Y400 93907 80009 80009 93907 80009 80009 93907 80009 0KB01 TK0588 2X013 86928 06666 73893 06666 5Y400 93907 5Y400 5Y400 93907 5Y400 5Y400 93907 5Y400 5Y400 93907 5Y400 TK1161 93907 85471 80009 0B445 80009 FOOT CABINET CHARCOAL GRAY POLYURETHANE 0JRO05 CABLE ASSY ADAPTER RS 232 9 PIN FEMALE TO 80009 25 PIN MALE MANUAL TECH USER OP 01 11 NTSC AND PAL MANUAL TECH PROGRAMMER RS232 FUSE CART 3AG 3A 250V 30SEC UL CSA CERT WSHR LOOP CLAMP 0 091 ID U W 0 5 W CLP CLAMP LOOP 0 25 ID PLASTIC VM700T Video Measurement Set Service M
159. UMENT RUN MODES MENU see Figure 6 49 In that menu select A AUTO RESET That causes all the diagnostic test to run one time before doing the system initialization Interactive Mode Interactive Mode provides a greater level of detail for most tests within a diagnostic routine than Power Up Mode Interactive Mode when selected displays the Change Run Mode soft key Touching the Change Run Mode soft key returns you to the SELECT RUN MODE screen In interactive mode each main test block runs and the test halts at the end of each block The main test title and all the subtest titles are shown with a Pass or FAIL label You are given the choices of continuing the testing looping on the selected test block re running the test block or changing the run mode for the testing program as shown in Figure 6 53 Selecting to continue resumes the testing and runs the next main test When all the tests within a diagnostic routine have been completed and the Continue soft key is selected the Select Run Mode screen is displayed 6 76 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Test meas t units min max result VMIPC Register Pass Readable Pass Writalbe Pass Bit 0 Control Pass Bit 1 Control Pass Bit 2 Control Pass Bit 3 Control Pass Bit 4 Control Pass Bit 5 Control Pass Bit 6 Control Pass Bit 7 Control Pass Continue Loop On Rerun Change Test Test Run Mode
160. VGOSOm ContolCircuity 1 Total Periodic and Random Deviations Pard measured at the power supply output connector includes peak to peak noise ripple switching spikes etc within a bandwidth from 5 Hz to 20 MHz 2 The housekeeping voltage VH is 11 4 V before the rest of the power supply comes on line VM700T Video Measurement Set Service Manual 6 93 Troubleshooting Procedures Troubleshooting the CRT 6 94 Display The display module is a 9 inch diagonal 640 x 480 pixel monochrome CRT unit The display is adjusted at the factory for optimum viewing brightness The interactive touch screen is attached in front of the CRT It can be removed for replacement of the touch screen or the display module if necessary If the CRT display fails the faulty unit must be removed and replaced For information on replacing the CRT display module refer to Removing and Replacing Display and Control Components on page 6 32 When a CRT display module is replaced minor adjustments may be necessary to center the display or fine adjust its brightness level Refer to Adjusting the Display on page 5 10 if readjustment is needed Part of the Touch Screen calibration procedure also makes some adjustments to the display If you replace the touch screen perform the touch screen calibration procedure on page 6 68 Isolating a CRT Display Fault Two types of CRT display failures can occur No display blank screen display and P
161. Voltage Selector was not set to the correct setting the fuse may have opened If the line fuse is good the master switch is ON the Line Voltage Selector set correctly and the power supply still does not operate troubleshoot the power supply P SFAIL POWER OVER TEMP O Figure 6 60 Front panel power supply and over temperature indicators If the Over Temp indicator is on and the instrument is still operating then an over temperature condition exists If the temperature continues to rise a power supply shutdown may occur The over temperature warning occurs at about 50 C and the power supply will shut down at about 60 C The ambient temperature may be too high to operate the VM700T or the flow of cooling air is cut off or restricted The VM700T should be shut off to let it cool down before a shutdown occurs VM700T Video Measurement Set Service Manual Troubleshooting Procedures Internal Checks If the PS Fail indicator is on then there is a power supply problem Turn off the master ON OFF switch on the rear panel of the VM700T and remove the holding screws from the right side as viewed from the front cover Slide the cover back about 8 inches to gain visual access to the power supply LED indicators Locate the power supply LED indicators near the front at the bottom of the chassis see Figure 6 61 Turn the master ON OFF switch back ON Front i OT
162. Waltham MA 02254 USA or 77 Milford Road Reading Berks RG1 8LG England The example connector is a distributor part System Adjustment Procedures 5 2 NOTE This equipment requires a 20 minute warm up period before starting the verification procedures The instrument must be powered on for at least 20 minutes After a board replacement certain adjustments may be needed to compensate the overall system performance The procedures in this section may be used to make those adjustments NOTE These procedures are not complete board level adjustments Most of the factory adjustments are made during testing before the boards are assembled into the VM700T The adjustments given here are those used to verify and adjust the instrument at the system level VM700T Video Measurement Set Service Manual Adjustment Procedure Adjust the Genlock This procedure verifies the VM700T genlock VCO by comparing it to a Voltage Controlled frequency standard and describes the adjustment process if that is needed Oscillator VCO Test Equipment Required m Signal generator Tektronix TSG 170A or equivalent for NTSC or Tektronix TSG 271 or equivalent for PAL Both signal generators are needed for dual standard instruments Frequency counter with external reference or Ratio Tektronix DC 503A TEGAM DC 503A or equivalent m Digital voltmeter with 3 1 2 digit display Termination 75 precision BNC Tektronix 011 0102 0
163. a Remove the right side cover panel refer to Cover Panel Removal and Replacement on page 6 8 Remove the card cage retainer refer to step 1 on page 6 16 The SDI board occupies the second from the top slot in the right side card cage see Figure 6 10 on page 6 17 Disconnect the cables from the SDI board at J8 J7 J10 and J5 see Figure 6 12 Remove the four retaining screws from the SDI Rear Panel Interface assembly see Figure 6 13 Remove the SDI Rear Panel Interface assembly by carefully pulling the four cables out through the hole in the chassis VM700T Video Measurement Set Service Manual 6 21 Maintenance 6 22 SDI Rear Panel Interface assembly A23 2nd hole Dress SDI GS AN CPU A5 Right side Board Figure 6 13 Installing the SDI Rear Panel Interface A23 assembly 2 Perform the following steps to replace the SDI Rear Panel Interface assembly a Position the SDI Rear Panel Interface assembly at the rear of the measurement set Slide all four cables through the second hole from the bottom on the rear panel as shown in Figure 6 13 b Secure the SDI Rear Panel Interface assembly to the rear panel using the four retaining screws c Slide the CPU A5 board halfway out of the measurement set d Lay the SDI multicolored ribbon cable on the CPU A5 board as shown in Figure 6 13 e Reinstall the CPU board VM700T Video Measurement Set Service Manual Mai
164. able 1 15 Bar Line Time Measurement Bar Level 61 or Back Porch Sync Level Sync to Bar Top Sync Bar Ratio Bar Tilt Rec 569 Line Time Distortion Rec 567 Bar Width Table 1 16 Bounce Measurement Peak Deviation Settling Time This section lists the specifications for each PAL measurement The accuracies shown for measurements with averaging capabilities assume the default averaging factor of 32 Test signals of known parameters are provided by characterized and traceable television signal generators to test the accuracy of these derived measurements Due to the statistical nature of digitizing measure ment methods reported results will meet these specifications 97 of the time All measurement accuracies specified are valid only with nominal inputs signals with an unweighted signal to noise ratio of at least 60 dB on the incoming signal and a termination accuracy of 0 025 Accuracies shown for measurements with relative mode accuracy assume that an averaging factor of 256 was used to create the reference Range specifies the extremes between which a measure ment can be made Relative mode accuracy 20 2 20 2 10 to 125 0 5 0 2 100 nominal 0 to 50 1 0 to 10 sec 100 msec VM700T Video Measurement Set Service Manual Specification Table 1 17 Burst Frequency Measurement Burst Frequency 100 Hz 0 5 Hz Table 1 18 Chrominance to Luminance Measurement Chrominance to Lumi
165. accessible on the rear panel Both are 9 pin male D connectors The Communications Setup file is found in the Configure Files directory press Configure and then touch the Configure Files soft key and contains parameter settings for both ports Configuring the Communication Setup file is covered in the VM700T Option 01 amp Option 11 User Manual Table 6 7 describes the signals the VM700T outputs and the input signals required on all the active pins of the serial ports Table 6 7 VM700T RS 232 connector pin outs Pin number Function Description 1 DCD Data Carrier Detect This signal typically comes from a modem and indicates that a phone connection is made 2 RD Receive Data The VM700T receives data on this pin 3 TD Transmit Data The VM700T transmits data on this pin 4 DTR Data Terminal Ready This pin is always high when the VM700T is turned on Modems typically require this signal to be a high level or they won t answer the phone 5 SG Signal Ground 6 DSR Unused in the VM700T and not internally connected 7 RTS Request To Send data With hardware flow control CTS RTS selected to the VM700T normally RTS connects to the CTS line of a terminal and the line is active when the VM700T is ready to receive data When the receive buffers of the VM700T are nearing capacity RTS goes inactive indicating to the sending device to stop transmitting data With software flow control XON XOFF selected or None s
166. al generator to the SDI Ch A input using a standard length cable 1 m length Be sure the SDI Ch A loopthrough is terminated using a 75 high frequency terminator 3 meter cable Cable clone r Total length 3 meters Ow re Figure 5 11 Cable requirements for adjusting the Cable Meter 5 26 VM700T Video Measurement Set Service Manual Adjustment Procedure d Touch the Calibrate soft key and then touch the Proceed soft key e Setthe cable clone for 100 m of cable or replace the standard length cable on the SDI Ch A input with 100 m of cable f Touch the Proceed soft key g Replace the 143 Mb signal with a 525 line 270 Mb 100 color bars signal Leave the SDI Ch A input terminated h Setthe cable clone for 0 m of cable or replace the 100 m of cable with the standard length cable i Touch the Proceed soft key j Set the cable clone for 100 m of cable or replace the standard length cable on the SDI Ch A input with 100 m of cable k Touch the Proceed soft key Replace the 270 Mb signal with a 525 line 360 Mb television signal Leave the SDI Ch input terminated m Set the cable clone for 0 m of cable or replace the 100 m of cable with the standard length cable n Touch the Proceed soft key o Setthe cable clone for 100 m of cable or replace the sta
167. al 6 49 Troubleshooting Procedures Troubleshooting Techniques 6 50 The following procedure is designed to assist in isolating problems which in turn expedites repairs and minimizes down time 1 Ensure that the malfunction actually exists This is done by running the diagnostics to ensure that the instrument is operating as intended by Tektronix Refer to Diagnostics beginning on page 6 55 for a description of the diagnostic tests and information on using diagnostics for troubleshooting module problems 2 Determine and evaluate all trouble symptoms This is accomplished by isolating the problem to a general area such as a replaceable module CAUTION Use extreme care when probing with meter leads or probes because of the high component density and limited access within the instrument The inadvertent movement of leads or a probe could cause a short circuit or transient voltage capable of destroying components 3 Determine the nature of the problem Attempt to make the determination of whether the instrument is out of calibration or if there has been a component failure Once the type of failure has been determined identify the functional area most likely at fault 4 Visually inspect the suspect assembly for obvious defects Most commonly these will be broken or loose components improperly seated components overheated or burned components chafed insulation etc In the case of overheated components determine the caus
168. am The Acquisition Memory board also adds a FIFO that allows the controller state machine to communicate information to the CPU without having to place the information in acquisition memory This is the FIFO that the SDI Format application s FIFO Overflow error refers to 3 50 VM700T Video Measurement Set Service Manual _ I Lee Performance Verification Self Diagnostics The Verification procedures in the this section are done with the covers on the measurement set to verify its operation and may be used to determine the need for readjustment After a board exchange certain adjustments may be needed to compensate the overall system performance Follow the directions found in the adjustment section of this manual when readjustment is needed Performance to published specifications is verified by other methods during a factory calibration of the measurement set You can configure the measurement set to run the diagnostics at power up or to bypass all diagnostics at power up Refer to Setting the Power Up Mode on page 6 70 As received from the factory the diagnostics are configured to be bypassed for a quicker startup The diagnostic routines of the VM700T Video Measurement Set check the operation of the digital hardware Passing the diagnostics is part of the performance verification procedure Hold down the Menu hard key when you power up the instrument After about 5 seconds release the Menu hard key In the VM700T Startup Menu shown in
169. an wire harness to the bottom of the left card cage Reconnect the VGA cable to the fan housing with a cable tie When reinstalling the fan make sure you have the fan positioned so that the air flow is out of the VM700T VGA Connector Board Use the following procedure to remove and replace the VGA Connector board 1 Perform the following steps to remove the VGA Connector board a Remove the instrument cover panels refer to Cover Panel Removal and Replacement on page 6 8 b Remove the attaching hardware for the VGA Connector board from the rear of the VM700T see Figure 6 26 c Pull the VGA Connector circuit board away from the fan housing and disconnect the VGA ribbon cable from the connector on the rear of the Connector board d Remove the VGA Connector board from the VM700T 2 Perform the following steps to replace the VGA Connector board a Reconnect the VGA ribbon cable to the connector on the circuit board b Position the VGA Connector board on the mounting plate against the inside surface of the rear panel under the fan housing c Align the holes in the circuit board with the holes in the rear panel mounting plate and install and tighten the attaching hardware d Replace the cover panels refer to Cover Panel Removal and Replace ment on page 6 8 VM700T Video Measurement Set Service Manual 6 43 Maintenance VM700T Rack Mounting Instructions Unpackaging Power Requirements A Changin
170. ange Frequency Range 143 Mb s 270 Mb s 360 Mb s Jitter Maximum for No Bit Errors 143 Mb s 270 Mb s 360 Mb s Cable Length Maximum for No Bit Errors Table 1 106 LTC Input Characteristic Electrical Characteristics Input type Input Impedance Signal Characteristics Format VM700T Video Measurement Set Service Manual Performance requirement Supplemental information BNC 75 terminated Channel on or off z 25 dB 1 MHz to 360 MHz z 15 dB 1 MHz to 360 MHz 800 mV 415976 25 20 ppm 20 ppm 20 ppm 2 ns p p for frequencies of 160 kHz and above Max jitter ns 320 jitter frequency KHz for frequencies below 160 kHz 1 ns p p for frequencies of 160 kHz and above Max jitter ns 160 jitter frequency KHz for frequencies below 160 kHz 0 8 ns p p typical for frequencies of 160 kHz and above Max jitter ns 130 jitter frequency KHz for frequencies below 160 kHz Equivalent to 200 meters of Belden 8281 cable Equivalent to 250 meters of Belden 8281 cable typical Performance requirement Supplemental information Miniature XLR gt 10 Longitudinal Time Code per IEC pub 461 1 43 Specification Table 1 107 SDI Output Characteristic Electrical Characteristics Output type Return Loss Power On Power Off Signal Characteristics Amplitude 20 to 8096 Rise Fall Time Table 1 108 Analog Ref Input Characteristic Electrical Characteristics Input type Return Loss Signal C
171. annel can either DC couple or DC restore clamp the video signal Clamping is applied before channel selection to allow independent clamping of video signals that are synchronous but mis timed relative to each other The bias level for each channel is summed with the buffered video just before clamping The clamp and bias generator supplies the analog clamp and bias voltages to each clamped input amplifier Three dual DAC devices are used to provide the six outputs used a clamp and bias level to the clamped input amplifier in each channel The DAC devices receive data and address information from the acquisition con troller board The 3 address bits select the appropriate DAC clamp or bias for channels A B or C while the 8 data bits are converted to the actual clamp or bias voltage Output from the clamped amplifiers is fed to a switching matrix that enables the user to select various combinations of input channels VM700T Video Measurement Set Service Manual 3 3 Theory of Operation Clamped Input Amplifier Channel Selection To Filter Cal Switch Switch Board Loop Through Inputs 8 5 A Ont gt ChanA 2 Differential Amplifier oq o Chan B l 2 5 Chan C 4 2 3 Cal DAC
172. ansmission paths This feature is used in conjunction with the VITS200 NTSC or VITS201 PAL insertion generators and the ASG100 or ASG140 Audio Signal Generators that are also equipped with the Audio Video Timing measurement The VM700T must have either Option 40 or Option 41 installed to operate with the Option 42 firmware Audio Options Option 40 and Option 41 Option 40 and Option 41 The VM700T audio measurement options expands the power of the VM700T Video Measurement Set to include comprehensive audio measurement capabili ties VM700T Option 40 and Option 41 capabilities include automated and manual audio measurements audio spectral analysis with harmonic analyzer W stereo monitoring real time display of audio parameters m multitone testing These options also enable the VM700T to continuously monitor audio test lines for the presence of a test sequence designed for automated testing the TEK sequence The audio option tests to ANSI standard T1 502 1988 EIA TIA 250 C or CCITT Recommendation O 33 The audio results received with automatic monitoring can be included in the VM700T Auto Mode video measurements display with the time and date of the last sequence received Timed reports and the logging of results can be performed automatically Also a file in the VM700T Measurement Results directory is updated each time an audio auto test sequence is received and measured Option 40 has two stereo input channels conn
173. anual TK2548 TK2548 71400 85480 5Y400 Mfr part number 390 1021 03 390 1021 03 821 12790 024 390 1023 00 390 1023 00 821 12790 024 390 1022 00 390 1022 00 821 12790 024 367 0366 00 211 0755 00 213 0940 00 IRR 7100 18 2B ORDER BY DESC C 720 3 ORDER BY DESC C 1252 390 1020 04 821 12790 024 390 1025 01 390 1025 01 821 12790 024 390 1028 01 390 1028 01 821 12790 024 390 1021 03 390 1021 03 821 12790 024 ORDER BY DESC ORDER BY DESC ORDER BY DESC 348 0596 00 200 3634 01 ECM 161 0066 00 011 0102 03 ORDER BY DESC 174 3726 00 070 9647 XX 070 9650 XX MSL 3 C191 343 0136 00 10 11 Replaceable Mechanical Parts Replaceable parts list cont Fig amp index Tektronix Serialno Serial no number effective discontd Qty amp description Mfr code part number OPTIONAL ACCESSORIES 31 161 0066 09 1 CA ASSY PWR 3 0 75MM SQ 250V 10A 99 2W733 ORDER BY DESC INCH STR IEC320 RCPT EUROPEAN 32 161 0066 10 1 CA ASSY PWR 3 1 0 MM SQ 250V 10A 2 5 TK2541 ORDER BY DESC METER STR IEC320 RCPT X 13A FUSED UK PLUG 13 FUSE UNI 33 161 0066 11 1 CA ASSY PWR 3 1 0MM SQ 250V 10A 2 5 METER 80126 ORDER BY DESC STR IEC320 RCPT AUSTRALIA 118 8792 00 1 PRINTER EPSON SERIAL 80009 118 8792 00 174 2740 00 1 CA ASSY SP ELEC RS 232 4 28 AWG 72 INCH 25 80009 174 2740 00 POS FEMALE D SUB X 25 POS MALE D SUB 018 0225 00 1 CKT BD ASSY SERIAL INTERFACE CARD 80009 018 0225 00 W MANUAL FOR EPS
174. ard Refer to Removing and A1 Replacing the Analog Input Board Screen brightness does Faulty CRT display module Replace the CRT module Refer to Removing and not adjust Replacing the CRT Display Faulty front panel A10A1 Replace the front panel keypad board assembly A10 or keypad board A10A2 Refer to Removing and Replacing the Keypad Board assembly Faulty display memory Replace the display memory SIMM on the CPU board SIMM on the CPU board Fault display memory Replace the CPU board This action requires a circuit on the CPU board complete reprogramming for the replacement CPU board No GPIB Operation Bad orloose GPIB cable Check GPIB cable connection Replace the GPIB cable No controller or incorrect Check for correct controller operation controller configuration Faulty GPIB Interface Replace the GPIB interface board board No RS232 Operation Incorrect RS 232 cable Check for correct cable and port connection Incorrect communication Check for correct parameters in Communication parameters Configuration file Faulty 1 O board Replace the I O board 6 54 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Diagnostics Diagnostics in the VM700T Video Measurement Set are divided into two sets low level and high level The distinction between the two types is based upon the operating system those diagnostics that run before the instrument s operating system is booted are refe
175. are and requires the appropriate programming and upgrade software disks and a personal computer connection to the parallel printer port Resetting the option key should only be needed if the VM700T does not boot up after a firmware upgrade Its use requires knowing the authorized Option Key for the instrument VM700T Video Measurement Set Service Manual 6 65 Troubleshooting Procedures Accessing the Diagnostic Utilities To access the diagnostic utilities perform the following steps 1 Turn off the VM700T 2 Press and hold the Menu button as you turn the power back on 3 After the VM700T beeps twice release the Menu button The VM700T Startup Menu is then displayed see Figure 6 40 4 Use the front panel knob to select U in the menu and then press the Select Line button This displays the Utilities Menu shown in Figure 6 41 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection VM700T STARTUP MENU Key Selection Instrument RUN MODES Menu UTILITIES Menu Low Level DIAGNOSTICS Menu Diagnostics CONFIGURATION Menu Diagnostics HELP Menu Calibrate TOUCH PANEL INTERFACE qa zz Reprint Abort Menu Input your selection Figure 6 40 VM700T Startup menu Low Level Diagnostic Interface knob moves cursor Select Line inputs selection UTILITIES MENU Key Selection ERROR L0G utilities NVRAM utilities REPR
176. are the failure symptoms with the information in Table 6 3 on page 6 52 and run the self test diagnostics to isolate a problem High Level Diagnostic Errors File When user selectable diagnostics are run at power up or during DiagsLoop refer to Diagsloop on page 6 77 all errors detected are written to the Diagnostic Errors file found in directory nvram0 ConfigFiles The Diagnostic Errors file is automatically created when an error is detected by user selectable diagnostics NOTE The maximum capacity for the Diagnostic Errors file is 100 lines If the number of errors detected produces a longer file the earliest results are scrolled out and a message stating that fact is included VM700T Video Measurement Set Service Manual Troubleshooting Procedures Low Level Diagnostic Interface knob moves cursor Select Line inputs selection INSTRUMENT RUN MODES MENU The instrument will be reset to run in the mode selected below overriding current boot switch settings Key Selection N NORMAL POWERUP Start Instrument in Powerup Mode Current Powerup Mode is QUICK START abort this menu and go to the DIAGNOSTICS CONFIGURATION MENU to change it P ee POWERUP DIAGS scr menn Do Diagnostics start Instrument QUICK START n dirimere Skip Diagnostics start Instrument L LOW LEVEL DIAGS LOOP Loop on Low Level Diagnostics D HIGH LEVEL DEBUG Start Instrum
177. assembly 15 Disconnect the flat cable and the green channel A cable from the SDI Rear Panel Interface assembly 16 Check each of the wires in the flat cable and the green cable for continuity 17 If the cables are good replace the SDI Rear Panel Interface assembly VM700T Video Measurement Set Service Manual 6 101 Troubleshooting Procedures 6 102 No Signal From the SDI Ch B Input side SDI board back side Pin 8 of J5 Figure 6 65 SDI board cable connections and J5 pinouts Perform the following steps when the VM700T will not display a known signal on the SDI Ch B input but the SDI Ch A input operates 1 Connect a digital video signal to the SDI Ch B input and set the VM700T to display the channel B signal Swap the SDI Ch A and SDI Ch B cable connections on the SDI board at J7 and J8 see Figure 6 65 Connect the signal input to the SDI Ch A input connector leave the VM700T front panel set to display the channel B signal Check that there is a signal display If there is still no signal display on channel B replace the SDI board If there is a signal on channel B replace the SDI Ch B cable VM700T Video Measurement Set Service Manual Troubleshooting Procedures No Signal From the Perform the following steps when the Analog Ref input does not operate but the Analog Ref Input SDI Ch A input operates 1 2 Connect an NTSC television signal to t
178. ating information drives a triple timer counter U6 The ATRIG BTRIG and CTRIG outputs from the triple timer counter drive a one shot multivibrator on the analog input board Trigger pulses are generated for each line where clamping is to be applied These pulses determine the point on a line where clamping begins other control lines on this board control circuitry on the analog input board that sets the clamp level and duration VM700T Video Measurement Set Service Manual Theory of Operation CPU SYSTEM BUS STATUS PULSES FROM BOARD TO ANALOG INPUT BOARD CLAMP COUNTERS 32 BDO 31 00 31 A2 10 ADDRESS BUFFER 16 BD16 31 STATUS COUNTERS CLAMP COUNTERS ADDRESS LATCH CONTROL BA10 15 A24 31 A0 1 ADDRESS DECODER A1223 CONTROL CONTROLLER ASIC NNNNNNN LSYNC BAO 15 CONTROL 2 TTL TO ECL 2 CONVERTER MODE CONTROL OE SEQUENCER ADDRESS BUFFER Lp E SEQUENCER gt CLR ADDRESS sclk OE DATA LATCH 13 BCDO 12 ADDRESS TRIGGER RAM em a ACQUISITION A SECTION TAO 3 3 SD29 31 gt REGISTER SCLK y CONTROL SEQUENCER STATIC RAM 16K X 32 14 SMA0 13 500 31 32 SMA9 12 500 8 sD1 282 164 5012 27 CONTROL DAT 16 BIT COUNTER RCO TO DATA ACQUISITION SECTION CONTR
179. ator to 50 kHz do not change the output level To speed up the response to the frequency change toggle the Average hardkey off then back on again after the display has re stabilized Check that the amplitude is within 0 5 of the reference level stored in step 4 Reset the leveled sine wave generator for 3 6 MHz do not change the output level To speed up the response to the frequency change toggle the Average hardkey off then back on again after the display has re stabilized Check that the amplitude is within 0 5 of the reference level stored in step 4 Change the Filter parameter from NTSC BW Lim to Chroma BP by pressing the Move Expand hardkey Don t change the settings on the leveled sine wave generator To speed up the response to the filter change toggle the Average hardkey off then back on again after the display has re stabilized Check that the amplitude is within 0 5 of the reference level stored in step 4 Change the TV standard parameter to PAL by pressing the XY Arrow hardkey Change the leveled sine wave generator frequency to 4 43 MHz do not change the output level To speed up the response to the frequency change toggle the Average hardkey off then back on again after the display has re stabilized Check that the amplitude is within 0 5 of the reference level stored in step 4 Repeats steps 1 through 7 for channel B and channel C VM700T Video Measurement Set Service Manual 4 9 Per
180. cage connector b Align the circuit board connector pins with the main interconnection board connector and press firmly to seat the connector c Reinstall each of the four cables ensuring that they are firmly seated 4 Perform the following steps to replace the right side card cage retainer a Install the card cage retainer by first inserting its upper tabs through the chassis slots Complete the installation by guiding the retainer slots carefully over the circuit board locator tabs See Figure 6 9 b When the screw heads extend through the slotted holes lock the card cage retainer in position by sliding it to the right c Tighten the retaining screws d Install the cover panel refer to Cover Panel Removal and Replacement on page 6 8 VM700T Video Measurement Set Service Manual 6 17 Maintenance Acquisition Memory Board Removal and Replacement As you face the front of the VM700T in the operating position the Acquisition Memory board A18 is located in a card cage on the right side To remove this board you must first remove the right side cover and the card cage retainer You must also disconnect four cables from the circuit board Required Tools Use the following tools to remove the Acquisition Memory circuit board m Flat blade screwdriver 3 or inch blade W Pozidriv screwdriver 1X Procedure Use the following procedure to remove and replace the Acquisition Memory board 1 Perform the follo
181. ce are added to the list of menu choices To build a custom testing sequence select B Build to display the entire list of diagnostics for the selected board In Figure 6 37 Display Diagnostics was the selected set of tests The other low level diagnostics have a different list of test choices as appropriate for the board being tested VM700T Video Measurement Set Service Manual Troubleshooting Procedures Low Level Diagnostic Interface Display Diagnostic Build a new CUSTOM TEST SEQUENCE by selecting test from those listed Key Selects Unselects Video ASIC Video RAM Video Interrupt Int l Brite DAC Ext Brite DAC Int l RAM DAC Ext 1 RAM DAC e gt Reprint Q Abort Menu Select All Un Sel All Done Selecting Selection s NONE Figure 6 37 Build CUSTOM TEST SEQUENCE menu for display When the menu first appears there are no selections made as indicated in the figure To add a test to the list rotate the large control knob to highlight the choice then press the Select Line button The selected choices are indicated by opening and closing angle brackets around the key letter and shown in the selections list You can select all the choices in the list by highlighting the and selecting it All the choices can be unselected by highlighting the and selecting it After you have made the test selections you want in the custom list
182. cedure 4 24 VM700T Video Measurement Set Service Manual SDI Option 1S Performance Verification This section contains the performance verification procedure for Option 1S The test equipment required to perform the Option 1S verification procedures is listed in Table 4 7 Test equipment examples are based on the test equipment that many customers and the Tektronix service centers have installed for supporting the VM700 family of video measurement sets Substitute test equipment meeting the minimum specifications may be used if available Table 4 7 Test equipment required for Option 1S verification Test equipment Minimum specification Example Leveled sine wave Output source resistance 50 Q 1 Amplitude Checking Eye Diagram Tektronix SG5030 generator accuracy at 67 5 MHz 3 Amplitude flatness amplitude accuracy and at 550 MHz 4 of 50 kHz reference frequency response Digital television signal SMPTE 259M SDI signals 270 Mb 525 line Serial digital television test Tektronix TG2000 Signal generator 10096 color bars 143 Mb 525 line NTC7 signal source Generation Platform combination 360 Mb 525 line 10 step DVG1 generator module with Option S1 SDI signal jitter Amplitude range of 0 to 15 ns 10 at 2 ns Frequency range of 50 Hz to 10 MHz Variable vertical signal timing of 262 lines Television signal generator Nominal NTSC video signal synchronized with a Analog television signal seria
183. consists of register files and a controlling device The controller makes the synchronous register files behave as a FIFO file This block is the control and timing center of the Acquisition system It handles static RAM access arbitration CPU dual porting state machine instruction interpretation CPU handshaking the real time control FIFO control Min Max control static RAM control and address sequencing for these RAM The acquisition control clock circuit crystal oscillator running at 20 000 MHz Various delayed versions of it are derived by a delay line The clocks are used in the acquisition ASIC for accurate timing of the control activities One clock output is fed to the controller section Because the Acquisition Controller board has its own 20 MHz clock it is independent of the CPU microprocessor the CPU microprocessor interface is asynchronous into the acquisition section of the board The data bus interface controls connection between the CPU data bus and the acquisition data bus to allow static RAM accesses The acquisition memory consist of sixteen 64 K x 4 bit fast 25 ns or lower access times static type RAM in two rows of eight devices with 17 total address bits and 32 bit wide data bus The min max ASIC keeps a running record of the minimum and maximum video data read from the FIFO as well as latching whether a line or frame pulse or an over flow or under flow has occurred Reading the Min Max results resets the circui
184. cted to a write read test using the test patterns 0x55555554 OxAAAAAAAA OxFFFFFFFE 0x00000000 0x33333332 OXCCCCCCCC 0 77777776 and 0x88888888 If the data written does not match the data read the test fails and a message indicating expected and actual results is printed to the console Each of the 2 SDI channels on the board can be forced into a manual lock mode by setting the autorate bit for the channel bit 1 for channel A and bit 6 for channel B in control register 0 to 0 When this is done bits lt 3 2 gt and lt 8 7 gt are used to select the manual rate desired 143 177 270 or 360 MHz These values are then reflected back in the status register in bits lt 4 3 gt and lt 9 8 gt respectively This fact is used to do a loop back test between control register 0 and the status register If the bits match the test passes Channel A is commanded to lock to each of 4 frequencies on the input 143 177 270 and 360 MHz and the frequency to which the channel locks is displayed If the front end logic detects the absence of a signal then this test is flagged as N A If there is no signal this is flagged N A Otherwise the SDI board is placed in autorate mode and after a waiting period the status register is checked to see which frequency the circuit locks to This frequency is displayed If there is no signal this is flagged N A Otherwise the manually determined frequency is compared with the frequency detected in aut
185. d RAM Li o c c 10 11 Load eae i2 18 HHHH A s e ox ne ams qme smao x Be x ipea Dc quee DET cup sie cien Dae f L w L1 1 DENEN EOS i 288250807 DTE Deum go HE NIELSEN I 2 eese T ede Ime EI R7 23 Input Selection Input Selection Peete X 24 Bias Control Range for each channel 25 Clamp for each channel 26 Tmes8Gan 8 Gain 27 Filter Slot n Sen slots EN through 5 1 Test depends on miscellaneous control logic on the A18 board independent of the hardware components indicated in Figure 6 55 Thetiming data path depends on the presence of the ADC board but does not rely on the ADC itself being operational VM700T Video Measurement Set Service Manual 6 83 Troubleshooting Procedures Auto Reset Running All Diagnostics Viewing Stored Diagnostic 6 84 Information If a malfunction causes the VM700T to reinitialize during normal operation the VM700T tries to initialize in Auto Reset mode This mode forces execution of all diagnostics both low level and high level regardless of the state of the Diagnostics Selection file If all diagnostic routines in the Diagnostics Selection file are set to Not Selected or if the Power Up diagnostics are set to Quick Start no high
186. d Press the VM700T front panel Configure button e Touch the Configure Files soft key and then touch the Source Selec tion Digital soft key f Highlight the Digital A line using the front panel knob and then touch the highlighted line to cause a box to appear around the current selection g Turn the knob to select Auto Detect touch the Accept Input soft key and then touch the Update amp Exit soft key to exit the configuration file h Press the VM700T front panel Measure button i Touch the SDI soft key and then touch the SDI EyeDiagram soft key j Press the VM700T front panel Menu button k Touch the Waveform soft key and then select Full Signal on and Free Run off Check that the readout text in the upper right corner of the display reads 143 Mb NOTE You can set the Eye Diagram horizontal scale units to UI unit intervals or to ns nanoseconds To set the horizontal scale touch the Cursors Units soft key and then touch the Jitter Units soft key m Touch the Calibrate soft key only visible if the CPU dip switch S4 is set to Open and then touch the Horz Pos 143 Mbit soft key n Turn the front panel knob to center the left zero crossing of the Eye Diagram at approximately 0 15 UI 1 ns on the horizontal scale See Figure 5 13 o Touch the Horz Pos 143 Mbit soft key to save the adjustment A wait message will appear p Replace the 143 Mb signal on the SDI Ch A input with a 525 line 270 Mb
187. d displays the vectors if it finds a color bars test signal You can use the Select Line choice in both Waveform mode and Vector mode to quickly specify any line for display or automatic measurement if an appropriate video test signal is being measured Measure Mode Measure mode provides graphic displays of measurements such as noise spectrum group delay and K factor for adjustment or closer analysis of the measurement You can make relative to reference measurements against a stored reference to minimize or eliminate signal source errors Signal averaging can be used to reduce the effects of random noise in measurements where averaging is appropriate Picture Mode Picture mode permits you to quickly verify the signal source You can select line on the picture to view in either the waveform display or the vector display for analysis of that line Auto Mode mode makes standardized video measurements automatically including those specified in the RS 250B EIA 250C NTC 7 and RS 170A video signal standards You can select the limits used on the measurements to determine out of limits conditions The measurement set generates a caution or alarm message if a measurement falls outside the selected limits You can select the format for the auto mode measurement reports and schedule the report printing times Analog Digital Mode If your measurement set has Option 1S installed the VM700T resembles two Option 15 Only separate instrum
188. d displays the results Presently there is no formal method of rolling this ID field but installing and removing these resistors may provide a tool for manufacturing troubleshooting Hence the pass fail field will always show PASS The product configuration requires that any VM700T containing the SDI option also be equipped with a 1Mb acquisition memory on the Acquisition Controller board This test probes the Acquisition Controller board and displays the amount of acquisition memory found on the board Thus the pass fail field will always show PASS This check is intended to allow factory personnel to verify that the VM700T is properly configured for the SDI option The true detected size of the acquisition memory is reported If it is 1 Mb this test will PASS or else it will FAIL The acquisition memory size detected in the above test is compared against the size detected at system boot If the two are different this test will FAIL This test was put in because at one point in the development of the SDI board mismatches of this kind were seen The serial EEPROM U158 is used to store calibration constants It is written by the SDI Calibration application primarily although SDI_EyeDiagram also writes some additional calibration constants to it There are two tests in this group A standard library in the software is used to read and write this device The first time the device is written the library code writes the constant 5A hex to t
189. d together whenever possible Pick up the components by the body never by the leads Do not slide the components over any surface Servicing static sensitive assemblies or components should be done only at a static free work station Avoid handling components in areas that have a floor or work surface covering capable of generating a static charge Use a soldering iron that is connected to earth ground Use only special antistatic suction or wick type desoldering tools VM700T Video Measurement Set Service Manual Maintenance Customer Service For service parts module exchange returns or technical support in the United States call the Tektronix Customer Service line between 8 00 AM and 5 00 PM Pacific Time Monday through Friday at this phone number 1 800 833 9200 Customer service personnel will direct your inquiry to the proper support group Exchanging VM700T Modules If you call for a module exchange you must supply the instrument serial number the firmware version number accessed by pressing the Configure button and the module s complete part number to ensure receiving the correct replacement If the module you request is in stock it will usually be sent to you the same day After you receive the replacement module the faulty module must be returned immediately to Tektronix using prepaid common carrier freight Use the packaging material from the replacement module and the furnished shipping label to prepare the
190. d with a cotton swab or pipe cleaner dampened with isopropyl alcohol Abrasive cleaners should not be used If the circuit board assemblies must be removed for cleaning follow the instructions in the removal and replacement procedures of this section VM700T Video Measurement Set Service Manual Maintenance CAUTION Do not allow water to get inside any enclosed assembly or component N Do not clean any plastic materials with organic cleaning solvents such as benzene toluene xylene acetone or similar compounds because they may damage the plastic After cleaning allow the interior to thoroughly dry before applying power to the instrument Visual Inspection After cleaning carefully check the instrument for defective connections damaged parts and improperly seated transistors integrated circuits or circuit boards The remedy for most visible defects is obvious however if heat damaged parts are discovered determine the cause of overheating before replacing the damaged part to prevent additional damage Periodic checks of the transistors and integrated circuits are not recommended Repackaging the Instrument Repackage the instrument in the original manner to provide adequate protection If the original packaging is not available or is unfit for use repackage and identify the instrument as described here Identification Tag If the instrument is to be shipped to a Service Center for service or repair attach a tag
191. de dumping data to the DACS or receiving data from the A D converter Control Register Control Register is a 24 bit register three 8 bit shift registers that holds the control word that controls operating states on the analog board The serial control word is clocked into the shift registers The control bits from the relay control register are buffered by relay drivers to drive the state controlling relays Master Oscillator and master oscillator is a integrated circuit oscillator generating a signal at Clock Divider 18 432 MHz The 18 432 MHz signal divided by 3 and reapplied to the A D converter Inside the A D converter the 6 144 MHz input clock is divided by 2 to 3 072 MHz and supplied as an output The 3 072 MHz clock is also provided as an inverted output by the A D converter The 3 072 MHz clock is applied to a multiple divide by two divider where it is divided by 64 to supply the 48 kHz that is the effective sampling rate That 48 kHz is applied to the L R input of the A D converter The 48 kHz and the 3 072 MHz clock are also sent off the analog board The 18 432 MHz signal is also divided by 8 to produce a 2 034 MHz signal used by the digital to analog converters This signal clocks the control word to the control registers VM700T Video Measurement Set Service Manual 3 41 Theory of Operation Calibration DAC Floating Power Supply Grounds A control signal used to hold off the 2 034 MHz When
192. diagram Simplified block diagram of the power supply Audio Processor block diagram Audio Analog block diagram Audio Analog block diagram GPIB board location in the measurement set Block diagram of the GPIB interface option board GPIB rear panel arrangement Option 1S block diagram VM700T Video Measurement Set Service Manual 2 3 2 5 2 6 2 6 2 7 2 7 2 8 2 11 2 12 2 16 2 18 2 19 2 19 2 20 2 21 2 23 2 23 3 4 3 8 3 12 3 15 3 16 3 18 3 21 3 23 3 26 3 27 3 28 3 30 3 32 3 34 3 38 3 43 3 44 3 45 3 46 3 48 vii Table of Contents viii Figure 4 1 VM700T Startup Menu Figure 4 2 Instrument run modes menu Figure 4 3 Configure Figure 4 4 Power up diagnostics selection display Figure 4 5 Diagnostic selection file showing an unselected choice Figure 4 6 Option 40 cable connections level accuracy and flatness check Ern Eu Figure 4 7 Option 40 cable connections distortion measurement accuracy check 2 cc cece cece cece cece eee e hh hn Figure 4 8 Option 41 cable connections level accuracy and flatness check RE Ee ERE CERES Fo RE KU ES Figure 4 9 Option 41 cable connections distortion measurement accuracy ChecK cc cece cece cece cece eee hh hn Figure 5 1 Adjustment 1
193. ding procedure e Position the instrument on its right side and remove the four screws holding the CRT assembly to the VM700T chassis see Figure 6 23 Figure 6 23 Removing the CRT assembly retaining screws VM700T Video Measurement Set Service Manual 6 37 Maintenance Power Supply Interconnect Board VGA Board and Cooling 6 38 Fan Removal and Replacement f Slide the CRT assembly out of the chassis enough to remove the 10 wire connector at the rear g Remove the CRT assembly from the VM700T chassis and set it aside 2 Replace the CRT touch panel by performing step 1 in reverse order This section describes how to remove and replace the power supply the main interconnect board and the cooling fan Required Tools Use the following tools to remove the display and control components m Flat blade screwdriver 3 16 or 1 4 inch blade Pozidriv screwdriver 2X m Combination or open end wrench 5 inch Small wire cutters Power Supply Module The power supply module is located on the right side of the VM700T below the right side card cage You may remove the power supply by first removing the cover panels of the VM700T refer to Removing and Replacing a Cover Panel on page 6 8 for more information and turning the instrument upside down The following procedure describes removing and replacing the power supply NOTE The power supply
194. dio Analog checks Audio Processor board board Check F1 F2 check DC DC converter 15 V and 5 V check oscillator output pin 2 U53 Figure 6 63 Procedure for troubleshooting the audio option boards VM700T Video Measurement Set Service Manual 6 95 Test Equipment Depot 800 517 8431 99 Washington Street Melrose MA 02176 FAX 781 665 0780 TestEquipmentDepot com Troubleshooting Procedures oe Le e F2 e 15Ve GND e 5V Y10 4 GND U53 031 M e e Figure 6 64 Test positions on the Audio Analog board 6 96 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Audio Option Diagnostics The Audio Processor board has no test points or adjustments Troubleshooting this board consists of running its diagnostics If the board passes the diagnostics it is operating correctly if it fails it must be replaced The video measurements of the VM700T are still usable if the VM700T passes the rest of the diagnostics Table 6 11 describes the Audio Processor board diagnostics and Table 6 12 describes the Audio Analog board diagnostics Like the other VM700T user selectable diagnostics these can be configured to run at power up on demand or in a continuous loop when either Option 40 or Option 41 is installed in the VM700T Video Measurement Set Table 6 11 Audio Processor board diagnos
195. duce errors into a functional instrument Adjust the VCO adjusting screw for the TV standard you are checking either NTSC or PAL for a DVM reading as close as possible to 0 V 0 V 250 mV or better The VCOs are located in metal housings on the Genlock board near the back of the Display Monitor CRT see Figure 5 1 NOTE If your instrument is a dual standard instrument check both VCOs before continuing with step 9 10 11 12 13 Disconnect the DVM from the VM700T and reinstall the instrument covers Disconnect all signal inputs from the VM700T then wait 5 minutes while the internal temperature of the instrument stabilizes Press the Measure hard key and touch the Video soft key if necessary to recall the Video measurement menu Touch the Burst Frequency soft key With no signal applied the VM700T displays a warning message that tells you to check the signal source because a signal cannot be found The burst frequency measurement starts automati cally after 3 seconds the Loss of Sync indicator blinks Press the Menu hard key and touch the Reference soft key in the menu display VM700T Video Measurement Set Service Manual Adjustment Procedure CHAN CHAN R555 J922 J923 A4 Filter Switch board LI
196. dule VM700T Video Measurement Set Service Manual Troubleshooting Procedures Troubleshooting Option 40 and Option 41 Audio The purpose of the troubleshooting techniques described here is to isolate an audio option fault to one or both of the audio boards You can use the audio diagnostics refer to Audio Option Diagnostics on page 6 97 to help isolate the fault After isolation the faulty board s may be exchanged to make a repair Board level audio option faults can be isolated by following the steps shown in Figure 6 63 The Audio Processor board has no test points or adjustments Troubleshooting this board consists of running its diagnostics If the board passes the diagnostics it is operating correctly but if it fails it must be replaced Diagnostics are also used to verify the Audio Analog board performance However isolating a diagnostic failure to a fault on this board also requires performing the additional checks shown in Figure 6 63 Figure 6 64 shows the Audio Analog board locations for the checks listed in Figure 6 63 Refer to Option 40 and Option 41 Audio Boards Removal and Replacement on page 6 11 for information on removing and replacing the audio option boards in the VM700T Enter diagnostics menu Run Bad Audio Processor Audio Processor diagnostics board Run Does not pass Audio Analog diagnostic diagnostics Does not run Passes Bad Bad Perform checks Audio Analog or Au
197. e A AUTO RESET Mode C CUSTOM Mode Reprint Q Abort Menu Input your selection Figure 6 35 Low level diagnostic OVERALL RUN MODE menu VM700T Video Measurement Set Service Manual 6 61 Troubleshooting Procedures 6 62 Custom Run Mode Choices The Custom Run Mode menu shown in Figure 6 35 permits configuration of the diagnostic testing sequence You can select the Power Up mode the Auto Reset mode or a Custom run mode Low Level Diagnostic Interface CPU Diagnostic Configure CUSTOM RUN MODE parameters as desired build edit sequence then select RUN to begin execution Key Selection S SEQUENCE Type CUSTOM 1l Advance Mode MANUAL 2 Result Display Mode SHOW ALL 3 Result Logging Mode B BUILD New Test Sequence Reprint Abort Menu Input your selection Figure 6 36 Custom run mode menu From this menu you can select how the diagnostic advances to the next test as Automatically Advance on Pass Advance on Fail or Manually You can select how the results are displayed from the choices of Show Show Main Results or Show Minimum Required Results How the results are logged is also selectable from a choice of Log the Main Results Log all the Test Results Log the Minimum Required Results and Disable Results Logging After you have built a custom test sequence the added choices of running the test sequence and editing the test sequen
198. e signals or signals Required from a generator that have the appropriate test signals in the vertical interval No useful measurement information is displayed if the test signals are not correct for the measurement being made Bandwidth bandwidth of the measurement set is 0 Hz DC to approximately 6 8 MHz video signals Connecting Inputs and measurement set has three video loop through inputs one external sync Outputs loop through two RS 232C DTE ports a Centronics compatible printer port and a VGA output connector on the rear panel Figure 2 3 The audio options Option 40 and Option 41 add appropriate connectors for application of the audio signals to the option circuitry The GPIB Interface Option 48 add a standard GPIB connector for remote control and GPIB hardcopy output You can connect any video signal of the appropriate format to any of the three video inputs for normal operation The serial ports Port 0 and Port 1 can be used for output to serial printers or for remote control of the measurement set The printer output port supports Centronics compatible parallel printers The VGA output provides support for viewing the measurement set display on a remote VGA monitor Certain options such as Camera and Component require connections to specific inputs for correct operation Refer to the appropriate option user manual when connecting signals to make those option measure ments VM700T Video Measurement Se
199. e High Performance Clock Recovery block the ADC generates Eye information When fed the control voltage from the jitter demodulator it generates the jitter waveform Wander Detector The Wander Detector block uses a high precision oscillator to provide the time base for precise measurement of minute differences in the interval between TRS marks This timing information is sent down the analog data path for further processing by the instrument software SDI Regenerator The SDI regenerator takes the signal from the equalizer for use as the SDI signal to be output It does not regenerate the clock NOTE The signal from the SDI Ch A input to the SDI regenerator is interrupted whenever an analog application is run AES Audio Receiver The AES audio receiver recovers the external audio serial data stream It outputs a serial data stream that is converted to parallel data by the audio video MUX VM700T Video Measurement Set Service Manual 3 49 Theory of Operation Analog Sync Detector The analog sync detector recovers line and frame sync from the Analog Reference input signal LTC Receiver The LTC Receiver block translates the LTC signal into registers that can be read by the CPU Modified Acquisition modified Acquisition Memory board contains all the analog circuitry plus a Memory Board series of to select between the analog and digital data streams and to change the handling of the flags portion of the data stre
200. e VM700T proceeds with system initialization To bypass each user selectable diagnostic as each begins to run or at any time during the running of the diagnostic press the Abort Diagnostic soft key The VM700T proceeds to the next selected diagnostic in the Diagnostics Selection file After the last selected diagnostic either runs or is aborted the VM700T proceeds with system initialization Low Level Diagnostic Interface SPECIAL INSTRUMENT POWER UP MODES These modes are accessed by powering up the instrument with the indicated button s held in The instrument will beep twice and recognize the mode about 5 seconds after power up after which the buttons must be released NOTE The Boot Switches MUST be in their Factory Default position ALL CLOSED to access these modes POWER UP MODES BUTTON S TO HOLD IN QUICK START INSTRUMENT Waveform RUN STARTUP MENU Menu REPROGRAM INSTRUMENT Display amp Waveform amp Auto Press Any Key to Continue Figure 6 39 Special power up boot modes Diagnostic Utilities diagnostic utilities include selections for viewing or clearing the error log clearing the file system and CPU reprogramming the Flash ROM with the appropriate software and uploading programs showing the firmware date codes finding the instrument ID number and resetting the Option Key Reprogramming the Flash ROM will only be used for actually upgrading the firmw
201. e front panel knob to highlight the source A B C for which you are specifying an audio input and an audio source file Touch the highlighted audio input 1 2 or 3 to select it Rotate the front panel knob to change the audio input selection Touch the highlighted source file to select it Rotate the front panel knob to change the audio source file selection if you are using an audio source file other than the system default When you have specified the audio inputs and source files touch the Accept Input soft key If the change is correct touch the Update amp Exit soft key otherwise touch the No Change amp Exit soft key VM700T Video Measurement Set Service Manual 4 19 Audio Option 41 Triple Input Verification Procedure NOTE If you change audio input and source files and then decide to exit the directory and cancel the change you must press the Accept Input soft key followed by the No Change amp Exit soft key The measurement verifies that you want to exit the Source Selection Audio directory and cancel any changes by asking you to touch the No Change amp Exit soft key again Check Level Measurement Accuracy and Flatness Specifications Checked Option 41 Level Accuracy and Flatness 4 20 This procedure verifies flatness and measurement accuracy by checking signal levels at specified frequencies NOTE Frequencies and levels checked are not specified in this procedure If the measurement accu
202. e mode on the VM700T Then touch the Measure Sinewave soft key The measured reading is the reference used to compare the rest of the measurement to It should be approximately 500 mV peak to peak Set the sine wave generator for a frequency of 4 424959 MHz at a level of 3 82 dBm Check to see that the measured amplitude is within 0 02 of the reference level measured in step 30 If it is not adjust C57 MID FREQUENCY until the measured value is within 0 0246 Set the sine wave generator for a frequency of 5 793146 MHz at a level of 3 81 dBm Check to see that the measured amplitude is within 0 55 of the reference level measured in step 30 Power off the VM700T and remove all the test cables Reinstall the instrument cover panels Run the Diagnostics final test is to run the complete set of VM700T diagnostics to verify that the system passes the tests 1 2 5 20 Press and hold the Menu button and power on the VM700T After about 10 seconds you should hear two beeps from the VM700T Release the Menu button In the VM700T Startup Menu shown in Figure 5 8 use the large control knob to select R Instrument Run Modes Menu VM700T Video Measurement Set Service Manual Adjustment Procedure Low Level Diagnostic Interface knob moves cursor Select Line inputs selection VM700T STARTUP MENU Key Selection Instrument RUN MODES Menu UTILITIES Menu Low Level DIAGNOSTICS Menu D
203. e of overheating and correct the cause before reapplying power 5 Remove defective modules and exchange them with the factory Refer to Removal and Replacement Instructions on page 6 6 Refer also to Customer Service on page 6 3 for information on the board exchange repair service WARNING High voltages are present inside the VM700T chassis These voltages can cause serious injury Leave all service procedures that require removing instrument covers to qualified service personnel Troubleshooting the VM700T is a matter of following a logical series of steps that isolate a problem to a specific system module such as a circuit board power supply or display monitor After isolating the problem repair consists of replacing the faulty module and checking the instrument for correct operation VM700T Video Measurement Set Service Manual Troubleshooting Procedures Some VM700T faults can be isolated to just one system module Correcting these faults requires replacing the faulty module Other faults may be caused by one or more defective system modules In either case the VM700T diagnostics routines can assist in isolating the fault to field replaceable modules These routines can also evaluate each of the instrument s major hardware components to provide a high degree of confidence that measurement results produced by the instrument are correct The best way to repair multiple module faults is to replace one module at a time checkin
204. e square highlights and beeper sounds SQUARE LOCATIONS SEQUENCE SQUARES will appear near Screen the screen corners 1 2 SEQUENCE will be 1 2 3 4 3 4 as indicated to the right Figure 2 4 Touch screen calibration panel VM700T Video Measurement Set Service Manual Operating Information 6 After you have touched the dots at all four corners a screen showing the panel calibration factors is displayed see Figure 2 5 From that screen you can press any key to return to the startup menu PANEL CALIBRATION VALUES XSCALE 471 XOFFSET 292 YSCALE 398 YOFFSET 231 Press Any Key to Continue Figure 2 5 Panel calibration values NOTE Panel calibrations values vary greatly depending on the version of touch panel that is installed in your instrument The sample values shown are typical of an older touch panel Setting the Power On You can configure the measurement set to always skip the power on diagnostics Mode to always run them at power on To access the diagnostics menus l Press and hold the Menu button while turning on the power to display the VM700T Startup menu shown in Figure 2 2 on page 2 5 In the startup menu highlight the C in the Diagnostic Configuration line and press the Select Line button This brings up the Diagnostics Configuration menu shown in Figure 2 6 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection
205. e wave generator for a 2 Vrms output at 1 kHz and set the second sine wave generator for a 0 02 V 20 mVnys at 3 kHz These two signals add across the termination resistance to produce a 1 kHz signal with a 1 third harmonic distortion Run the Audio Analyzer measurement and check for a THD N reading of 0 9 to 1 1 Move the input from the generators to the right channel and repeat step 2 part d Check Frequency and Phase Measurement Accuracy Specifications Checked Option 40 Frequency Accuracy and Channel Phase Difference This procedure requires an accurate frequency sine wave generator or a digital counter to accurately set the frequency The phase measurement requires that both channels have the same signal applied through equal length cables This procedure checks the following parameters Frequency accuracy 1 Hz or 0 01 1 digit whichever is worse for inputs of 60 dBu or greater in the frequency range of 20 Hz to 20 kHz Channel phase difference 1 for inputs of 40 Hz to 20 kHz 2 for inputs of 20 Hz to 40 Hz at a level of 40 dBu or greater Connect the sine wave generator output to both the left and right inputs of the Audio board see Figure 4 6 Set the sine wave generator for a frequency and amplitude in the specified frequency and amplitude range of the Audio option 20 Hz to 20 kHz amplitude of 60 dBu or greater NOTE Use a test signal level of at least 60 dBu and test at
206. ected through mini XLR connec tors Two mini XLR adapters are provided to make signal connections to the inputs Option 41 provides for three stereo input channels connected through a male DB 37 connector A female DB 37 connector is provided with Option 41 to use for fabricating the interconnecting cable that applies the signals to be measured to the three stereo inputs of the VM700T Either Option 40 or Option 4 may be installed in the VM700T not both VM700T Video Measurement Set Service Manual 7 3 Options Serial Digital Interface Option 1S Option 1S provides the capability to display capture and analyze 270 Mbit 525 line and 625 line serial component 143 Mbit serial composite and 360 Mbit serial component digital video signals The Option 1S hardware consists of an SDI circuit board that installs into the right side card cage a two board input assembly that mounts onto the measurement set rear panel updated instrument firmware and several interconnecting cables The Option 1S rear panel connectors include two SDI inputs one loopthrough and one internally terminated in 75 a buffered SDI output of one of the SDI input channels an AES EBU digital audio input a Longitudinal Time Code input for time stamping logged error files and an analog loopthrough input to be used for a timing reference signal Option 1S provides the following key features m Automatic analysis of 270 Mbit component 143 Mbit composite and 360
207. ectro Static Damage instructions and the Customer Service information on the following pages VM700T Video Measurement Set Service Manual 6 1 Maintenance Preventing Electro Static 6 2 Damage This instrument contains electrical components that are susceptible to damage from electro static discharge Static voltages 1 kV to 30 kV are common in unprotected environments Table 6 1 shows the relative static discharge susceptibility of various semiconductor classes Table 6 1 Static susceptibility Relative susceptibility levels 1 Voltage MOS and CMOS 100 500 V ECL 200 500 V Schottky Signal Diodes 250 V Schottky TTL 500 V HF Bipolar Transistors 400 600 V JFETs 600 800 V Linear microcircuits 400 1 000 V est Low Power Schottky TTL 900 V TTL 1 200 V 1 Voltage equivalent for levels voltage discharged from a 100 pF capacitor through a 100 O resistance Observe the following precautions to avoid damage Minimize handling of static sensitive components Transport and store static sensitive components or assemblies in their original containers on a metal rail or on conductive foam Label any package that contains static sensitive components or assemblies Discharge the static voltage from your body by wearing a wrist grounding strap while handling these components Nothing capable of generating or holding a static charge should be allowed on the work station surface Keep the component leads shorte
208. ects the highlighted diagnostic touching the vertical center of the right half unselects it VM700T Video Measurement Set Service Manual 4 3 Performance Verification 5 Press the Update amp Exit soft key to write out save any changes to the file press the No change amp Exit soft key to leave the file as it was when it was last saved Power Up Diagnostics Selection Genlock Diagnostic Controller Diagnostic Acquisition Diagnostic ADC Diagnostic AnalogInput Diagnostic FilterBoard Diagnostic GPIB Diagnostic AudioProcessor Diagnostic AudioAnalog Diagnostic Rotate control knob to highlight the selection to be made Selected Line 8 Not Selected Figure 4 4 Power up diagnostics selection display As shown in Figure 4 5 the FilterBoard Diagnostic routine is in the Not Selected column and will not be performed Power Up Diagnostics Selection Genlock Diagnostic Control ler Diagnostic bp Acquisition Diagnostic the highlighted choice ADC Diagnostic AnalogInput Diagnostic FilterBoard Diagnostic GPIB Diagnostic AudioProcessor Diagnostic AudioAnalog Diagnostic Selected Line 8 Not Selected Figure 4 5 Diagnostic selection file showing an unselected choice 1 The AudioProcessor Diagnostic and AudioAnalog Diagnostic selections are available only with the VM700T Audio option GPIB Diagnostics is added to this list when the GPIB option is installed 4 4 VM700T Video Measurement Set Service Manual
209. eee ale Ro T Po 3 29 Horizontal Detect om i eese cine eee a wre hn are er ie Seta 3 30 HISD Voltage pte eins ret bie gies ore ils RR Wale od ea 3 31 Trace Rotation c esce ep e ere sie gts wre ends Siar Tere atus 3 31 Power Supply esee eee ee E wale etre ere Rack tcn 3 31 Input Power ee eR eh unr ere eget 3 31 Housekeeping Power Supply rea een 3 31 Inverter Switching Circuit eee eee nen 3 31 12V 15 V Regulators ein a eret rate TR Rel Ret 3 32 SONSING Pet eite eo ER eme e cus ate Der tuse REIR 3 33 Alarm THREE reU ope le CRT T E won 3 33 ban DHVe ror ro ete 3 33 Option 40 Audio 3 33 Audio Processor Board 12 3 33 Audio Processor Interface eese 3 34 Address Decoders zm oce du Avira cote eret ee ate er tec exte 3 34 BUS Butters co toute est etes Toe euis dune em Mt ere d beds d 3 34 Address BULLETS ren t ret ete aue as 3 34 Interrupt Generator Status Port gerere nea 3 35 Interrupt Generator etym RM he Rhe s 3 35 Data Butters ciara rele nie gies e te t eoe 3 35 Reset asaya
210. eives data on this pin Data 3 The VM700T transmits data on this pin Data 4 DTR Data Required for modem connections only This pin is always high when Terminal the VM700T is turned on When DTR is asserted the modem knows Ready it is connected to a live PC terminal 5 SG Signal Ground 6 DSR Data Set Unused in the VM700T Ready 7 RTS Request With hardware flow control CTS RTS selected normally RTS to Send data to connects to the CTS line of a terminal and the line is active when the the VM700T VM700T is ready to receive data When the receive buffers of the VM700T are nearing capacity RTS goes inactive indicating to the sending device to stop transmitting data With software flow control set to XON XOFF or with None selected RTS is always active 8 CTS Clear to With Flow Control CTS RTS selected the VM700T is enabled to Send transmit data by a high level on pin 8 and is disabled by a low level It is normally connected to the RTS line of a terminal With Flow Control None or XON XOFF selected the VM700T transmits data regardless of the CTS level 9 Unused in the VM700T Parallel Port Interface multipurpose I O controller provides the interface between the parallel port and the CPU Only the parallel port controller is used for this application 32 Bit Counter clock frequency of this counter defaults to 1 8432 MHz The clock frequency is controlled by bits from a status reg
211. elected RTS is always active 8 CTS Clear To Send With Flow Control CTS RTS selected the VM700T is enabled to transmit data by a high level on pin 8 and is disabled by a low level It is normally connected to the RTS line of a terminal With Flow Control None or XON XOFF selected the VM700T transmits data regardless of the CTS level 9 m VM700T Video Measurement Set Service Manual Troubleshooting Procedures NOTE Not all RS 232C devices use control lines as described in this section Refer to the instruction manual of the equipment you are connecting to the VM700T to determine exactly how it should be connected Table 6 8 gives the null modem cable configurations for 9 pin to 9 pin and 9 pin to 25 pin DTE connectors that should work in most cases for remote control and for viewing the output of the VM700T in debug mode The pin numbers listed for the Terminal DTE are the most common locations for the corresponding signals Table 6 8 Typical RS 232C null modem cable wiring connector DTE connector VM700T pin no Terminal VM700Tpinno Terminal pin no 11000 aom hom 7 zm TUS zm sm seo 4 DTR jc J4 0TR 6 DSR amp 8 DCD 5 Signal Ground 5 Signal Ground f5 Signal Ground 7 Signal Ground 6 Unused 608A else _ 20 0TR TETS bes ECTS ims 9 Unused RI 9 Unused R 9 Un
212. em NVRAM or select C to clear the CPU NVRAM and then press the Select Line button Each NVRAM selection has its own screen explaining what is done and what the resulting state of the file system will be after clearing The Clear File System Utility screen is shown in Figure 6 42 and the Clear CPU NVRAM Utility screen is shown in Figure 6 43 NOTE If you clear the CPU NVRAM you must recalibrate the touch screen 4 Press the Menu button to clear the selected NVRAM or press any other button to abort the utility VM700T Video Measurement Set Service Manual 6 67 Troubleshooting Procedures Low Level Diagnostic Interface CLEAR FILE SYSTEM UTILITY WARNING Clearing File System NVRAM will destroy All user files setups data etc The Diagnostic Selection file and the Diagnostic Errors file The instrument will revert to its Default NVRAM File System 11 diagnostics in the Diagnostics Selection file will be enabled and the Diagnostic Errors file will be deleted Press MENU BUTTON to clear NVRAM any other button to abort Figure 6 42 Clear File System Utility menu Low Level Diagnostic Interface CLEAR CPU NVRAM UTILITY WARNING Clearing CPU NVRAM will destroy The TOUCH PANEL INTERFACE calibration Optional Hardware presence status Low Level Diagnostics configuration Low Level Diagnostics Error Log Low Level Diagnostics NVRAM Map The DIAGNOST
213. en calibration panel 10 After the dots at all four corners have been touched a screen displaying the panel calibration factors is displayed as shown in Figure 5 6 From that screen you can press any key to return to the VM700T startup menu PANEL CALIBRATION VALUES XSCALE YSCALE 471 398 XOFFSET YOFFSET Press Any Key to Continue 292 231 Figure 5 6 Panel calibration values NOTE Panel calibrations values vary greatly depending on the version of touch panel that is installed in your instrument The sample values shown are typical of an older touch panel 11 If the power on display intensity is not satisfactory adjust the brightness level This adjustment is located on the bottom of the CRT display module NOTE The power up brightness level seldom needs adjustment in normal operation VM700T Video Measurement Set Service Manual Adjustment Procedure 12 Power off the VM700T and replace all cabinet covers and retaining screws 13 Hold the Auto button in and power on the instrument This runs the full set of diagnostics at power on Check that the instrument passes all diagnostic tests 5 14 VM700T Video Measurement Set Service Manual Adjustment Procedure Extended Adjustment Procedure Adjust the Frequency After a board exchange in the analog input section of the instrument the analog Response system may need readjustment This procedure first checks the
214. ent Removing the keypad board assembly and other display and control components from the front of the instrument also requires removing the bottom cover panel The four cover panels are positioned with slotted corner extrusions and fastened with screws to the instrument rear panel Removing each cover panel requires removing its fastening screws on the rear panel and sliding the panel toward the rear of the instrument and out of the grooves in the chassis frame Replacing each cover panel is the reverse of the removal procedure Required Tools Use the following tool to remove the cover panels W Pozidriv screwdriver 1X Procedure Use the following procedure to remove and replace the cover panels 1 Remove the screws at the rear edge of the cover panel to be removed 2 Remove the panel by sliding it carefully to the rear of the instrument and out of the grooves in the chassis frame see Figure 6 2 3 Replace the cover panel by guiding it into the chassis grooves sliding it all the way to the front of the instrument and installing the screws Figure 6 2 Removing a cover panel VM700T Video Measurement Set Service Manual Maintenance Board Removal and remove the I O board A20 you must first remove the left side cover panel Replacement and the retainers and screws holding the boards in the card cage Required Tools Use the following tools to remove the I O board m Flat blade screwd
215. ent You can select numeric value displays to confirm signal path quality or graphic displays for more detailed analysis of the applied signal The measurement set can be operated directly using the front panel or remotely using one of the RS 232C ports on the rear panel The standard measurement set is a rack mounted unit Refer to the VM700T Rack Mounting Instructions on page 6 44 for the rack mounting installation instruc tions The following unpacking and power requirements information is repeated there You can also order the measurement set as a cabinet style unit When you unpackage the measurement set keep the shipping carton and packaging material If you need to return the measurement set for servicing you will then have packaging available that provides adequate protection for shipment The VM700T Video Measurement Set operates with line frequencies of 50 Hz or 60 Hz over two line voltage ranges The nominal setting of the low voltage range is 115 VAC The nominal setting of the high voltage range is 230 VAC There are two power switches on the measurement set m The main power switch is on the rear panel above the power cord receptacle m The Stby On switch is on the front panel Both power switches must be on to operate the measurement set WARNING Dangerous voltages are present within the Power Supply module when the rear panel power switch is on regardless of the position of the front panel power switch Do not opera
216. ent in HL Debug Mode A Do EXTRA Diagnostics start Instrument Reprint Abort Menu Input your selection Figure 6 56 Instrument Run Modes menu Viewing Diagnostics You will not be able to view diagnostic results if the VM700T display either is Remotely not operating or is operating improperly The VM700T supplies a method known as Debug mode to view diagnostic results on a terminal or PC should the display be malfunctioning You can isolate a display problem to the display monitor by viewing the output signal from the VGA connector If that display is normal but there is no display on the CRT check the display monitor In Debug mode the VM700T redirects the low level diagnostics display data to the rear panel PORT 0 serial connector To view the diagnostics you must connect a terminal or PC to PORT 0 If you connect a PC you must also run a terminal emulator program on the PC to read the output from the VM700T In Figure 6 57 the Boot switch is shown in the setting that enables output to the serial I O port 0 That is with all switches set to the CLOSED position pushed in at top except S6 The password feature is also enabled by this switch setting but if the password file is empty a password is not needed to make file changes VM700T Video Measurement Set Service Manual 6 85 Troubleshooting Procedures 6 86 1 S2 53 54 55 56 57 58 Closed
217. ent location Adjust the Calibration This procedure adjusts the calibration DAC Run this procedure by selecting it DAC CalDAC with the soft key in the Diags directory Follow the directions displayed on the VM700T screen for adjusting the Analog Input board A1 amplitude and offset voltages Test Equipment Required m Digital voltmeter with 3 1 2 digit display m Non metallic flat blade adjusting tool Tektronix part number 003 1364 00 NOTE Run this procedure only if Verification Procedure 1 Measure Square wave yields incorrect results Adjusting the VM700T unnecessarily for example to get a better reading on a calibration result that is within limits can introduce errors into a functional instrument Adjusting the CalDAC 1 Press the Measure button and the Diags soft key 2 Press the CalDAC adjustment soft key VM700T Video Measurement Set Service Manual 5 9 Adjustment Procedure Adjust the Display 3 Remove the VM700T top cover and connect the digital voltmeter to TP610 on the analog input board A1 Adjust R474 CalDac Offset on the Analog Input board for 1 2793 V Press the C button Adjust R476 CalDac Reference on the Analog Input board for 0 0000 V Press the C button Check for a 41 2777 V x0 001 V reading at TP610 oS UV c Press the Measure button to exit the CalDAC procedure 10 Power off the VM700T and replace the top cover NOTE If you performed this procedure aft
218. ential Gain 0 to 100 FCC NTC 7 Composite VM700T Video Measurement Set Service Manual 1 27 Specification Table 1 77 Amplitude and Phase measurements cont Differential Phase FCC NTC 7 Composite Luminance Non linear Distortion FCC NTC 7 Composite Relative Burst Gain FCC NTC 7 Composite Relative Burst Phase FCC NTC 7 Composite Burst Amplitude 96 of sync 2596 to 200 of sync Horizontal Blanking Burst Amplitude 96 of Bar 10 to 80 of Bar 10 IRE to 0 496 0 4 IRE Horizontal Blanking 80 IRE when Bar is not used Sync Amplitude 96 of Bar 20 to 80 of Bar 20 IRE to 0 396 0 3 IRE Horizontal Blanking 80 IRE when Bar is not used Blanking Level 0 to 90 of Maximum Carrier Horizontal Blanking Sync Variation 0 to 50 of Maximum Carrier 0 0 396 for Zero Carrier 0 3 Horizontal Blanking to 50 of Bar when Zero for Bar and 0 3 IRE for no Carrier is not used 0 to 50 Zero Carrier and no Bar IRE when Zero Carrier and Bar are not used Blanking Variation 0 to 50 of Maximum Carrier 0 0 396 for Zero Carrier 0 3 Horizontal Blanking to 50 of Bar when Zero for Bar and 0 3 IRE for no Carrier is not used 0 to 50 Zero Carrier and no Bar IRE when Zero Carrier and Bar are not used Table 1 78 Frequency Response measurements Measurement Test signal Multiburst Flag Amplitude 0 to 9096 of Maximum 0 5 for Zero Carrier FCC Multiburst Carrier 20 to 130 of Bar 0 596
219. ents for Electrical Equipment for Measurement Control and Laboratory Use Compliance was demonstrated to the following specification as listed in the Official Journal of European Communities Low Voltage Directive 73 23 EEC amended by 93 68 EEC EN61010 1 A2 1995 Safety Requirements for Electrical Equipment for Measurement Control and Laboratory Use ANSI ISA 582 02 01 Safety Standard for Electrical and Electronic Test Measuring Controlling and Related Equipment 1994 IEC1010 1 Safety Requirements for Electrical Equipment for Measurement Control and Laboratory Use Table 1 9 Safety certification compliance Category Temperature operating Altitude maximum operating Relative Humidity maximum operating Equipment Type Safety Class Overvoltage Category Pollution Degree Description 15 C to 50 C 2000 Meters 8096 for temperatures up to 31 C decreasing linearly to 5096 to at 40 C Test and Measuring Class as defined in IEC 1010 1 Annex grounded product Mains Overvoltage Category II as defined in IEC 1010 1 Annex J Local level mains appliances portable equipment Pollution Degree 2 as defined in IEC 1010 1 Do not operate in environments where conductive pollutants may be present Note Rated for indoor use only VM700T Video Measurement Set Service Manual 1 7 Specification Table 1 10 Rear panel signal connectors Characteristic Port 0 and Port 1 Connectors GPIB
220. ents in one package one analog and one digital You can switch between the analog and digital functions by selecting Digital Mode or Analog Mode from one of these locations the Configuration menu two locations the Measure menu or through remote control NOTE To access any of the functions of Option 1S you must set the VM700T to Digital Mode To access any of the analog measurement applications of the VM700T you must set the VM700T to Analog Mode VM700T Video Measurement Set Service Manual 2 9 Operating Information When you switch between Digital Mode and Analog Mode the operation of the front panel buttons does not change except for the following five buttons Waveform Vector Picture Measure and Auto The Waveform and Picture buttons access the SDI Waveform and the SDI Picture applications respectively The Vector button accesses the SDI Lightning application The Measure mode button operation changes so that the measurement choices shown in the Measure menu will be only those relevant to the selected signal source type analog or digital When the VM700T is set to Digital Mode the Auto mode button provides direct access to the SDI Format Monitor application Option 1S adds a new soft key to the Measure mode screen and changes the name of one of the existing soft keys The new SDI soft key changes the measurement set to Digital Mode and displays the SDI applications The original Video soft key is renamed to Analog Vide
221. eplace the front panel keypad board assembly Refer or keypad board A10A2 to Removing and Replacing the Keypad Board Faulty display memory Replace the display memory module on the CPU board module or CPU board Replace the CPU board for bad display memory circuit Faulty touch panel control Replace the touch panel controller board ler board instruments with serial numbers B050100 and above only Noise at fixed intervals in Faulty acquisition memory Replace the acquisition memory board Refer to Line Spectrum mode board A18 Removing and Replacing the Acquisition Memory Board RAM test failure Faulty RAM memory Replace the RAM memory SIMM on the CPU board modules on the CPU board Faulty SIMM board socket Clean the SIMM board connector Check for firm connection Analog gain out of specifi Faulty ADC board A3 Replace the ADC board Refer to Removing and cation Replacing the ADC Board Faulty analog input board Replace analog input board Refer to Removing and A1 Replacing the Analog Input Board OVERTEMP status LED lit Faulty power supply Check power supply Refer to Power Supply Diagnostics in this section Faulty or blocked cooling Check cooling fan for operation and for obstructions fan blocking air flow Loose connections to Check cooling fan connections Refer to Removing and cooling fan Replacing the Cooling Fan Clogged or dirty front bezel Clean the front bezel air filters Refer to Cleaning the ai
222. eps twice to acknowledge the startup mode release the Menu button The VM700T then initializes directly into the Low Level Diagnos tics Interface with the VM700T startup menu as shown in Figure 5 2 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection VM700T STARTUP MENU Key Selection Instrument RUN MODES Menu UTILITIES Menu R U D Low Level DIAGNOSTICS Menu C Diagnostics CONFIGURATION Menu H Diagnostics HELP Menu T Calibrate TOUCH PANEL INTERFACE Reprint Abort Menu Input your selection Figure 5 2 VM700T startup menu 6 Inthe startup menu use the large control knob to highlight the T in the Calibrate Touch Panel Interface line Press the Select Line button to make the selection to calibrate The first touch screen calibration instructions are then displayed as shown in Figure 5 4 7 Use the large control knob to set the current setting to 8 This setting provides the best centering for a connected VGA monitor 8 Check the horizontal and vertical centering of the display If display positioning is not satisfactory off center or horizontal folded back adjust the appropriate control Horiz or Vert Centering located beneath the side retainer plate on the A5 CPU board board right side of the VM700T see Figure 5 3 to align the display on the CRT VM700T Video Measurement Set Service Manual 5 11 Adjustment Procedure
223. equency Luminance Non Linearity Multiburst Noise Spectrum SCH Phase Short Time Distortion Two Field VITS ID Vertical Blanking RS 170A horizontal blanking interval timing RS 170A vertical blanking interval FCC horizontal blanking interval timing 1 17 1 17 1 18 1 18 1 19 1 19 1 20 1 20 1 20 1 21 1 21 1 22 1 22 1 22 1 22 1 22 1 22 1 23 1 23 1 23 1 23 1 23 1 24 1 24 1 24 1 24 1 24 1 25 1 25 1 25 1 25 1 25 1 25 1 26 1 26 1 26 1 27 1 27 VM700T Video Measurement Set Service Manual Table of Contents Table 1 76 FCC vertical blanking interval timing 1 27 Table 1 77 Amplitude and Phase measurements 1 27 Table 1 78 Frequency Response measurements 1 28 Table 1 79 Incidental Carrier Phase Modulation 1 28 Table 1 80 Color Bar measurements 1 29 Table 1 81 Out of Service measurements 1 29 Table 1 82 Waveform Distortion measurements 1 29 Table 1 83 VIRS measurements 1 29 Table 1 84 Signal to Noise Ratio measurements 1 30 Table 1 85 O 33 Automatic audio test measurement specifications ess veis eem re I e I o RR RICE AQ RR AR CR S 1 31 Table 1 86 Tektronix automatic audio test measurement specifications aix xa RACE EROR ERA TON US REA ORC 1 32 Table 1 87 Frequency and Noise specifications
224. er getting out of limit results from Verification Procedure 1 Measure Squarewave return to Procedure 1 now This procedure adjusts the display after a monitor or CPU board replacement The replacement monitor when supplied by Tektronix has been aligned for proper operation in the VM700T but Trace Rotation a monitor control and vertical and horizontal centering and size CPU board controls may be needed to align the replacement display The final procedure is to set the power up display intensity and calibrate the touch screen Test Equipment Required m Non metallic flat blade adjusting tool Tektronix part number 003 1364 00 Adjusting the Display Monitor 1 Power off the instrument disconnect its power cord and remove the left and right side covers 2 Reconnect power to the VM700T press and hold the Waveform button when you turn the power on After the instrument beeps twice release the button and let it complete its power on initialization The waveform graticule is the default display at power on 3 Look at the lower left corner of the waveform graticule It should form a 90 degree right angle If not adjust the Trace Rotation control located on the left side of the monitor chassis to level the form graticule trace across the screen 4 Turn the VM700T off VM700T Video Measurement Set Service Manual Adjustment Procedure 5 Press and hold the Menu button while turning on the power After the VM700T be
225. erator to the VM700T channel A input terminate channel A with the 75 Q termination VM700T Video Measurement Set Service Manual 5 3 Adjustment Procedure 5 4 5 With the VM700T powered off remove the three top cover holding screws found at the rear of the instrument and slide the top cover panel back enough to expose the genlock board just behind the CRT module Power on the instrument and allow it to warm for 20 minutes if not already warmed up For dual standard instruments select either NTSC or PAL mode as needed for the VCO being checked This may be done by pressing the Measure hard key then the Video Standard soft key to identify the applied composite video signal source Then press the Waveform hard key to return to the Waveform mode Selecting the TV standard in this manner is temporary and the configuration returns to match that set in the Video Source file at the next power on Alternately you may use the Configure menus to set the Video Source file for the TV standard you have applied to the channel Connect the DVM plus lead to TP 86 on the Genlock board and the minus lead to chassis ground Check that the voltage is about 0 V 0 V 250 mV The VM700T must be locked to the external input signal NOTE If the VM700T meets the limits described skip step 8 and go to step 9 Adjusting the VM700T unnecessarily for example to get a better reading on a calibration result that is within limits can intro
226. erface Clamp Counters Status Counter ECL To TTL Conversion Data and Address Latches onto the BCDO 12 Bus Trigger RAM Sequencer State Machine Dynamic Settings Front Panel Board A10A1 VM700T Video Measurement Set Service Manual 1 B B B B B B B B B RRR gt gt C9 C92 DW WW Ww Ww Table of Contents Keypad Board A10A2 nates pe n 3 28 Control Knob eret Re ove ends Seana etn te gets 3 28 Push B ttons ies eerte Rr UR e rte RR DT od ers 3 28 EBDSZ Atos E tette ng 3 28 Main Interconnect Board Left and Right A11 3 29 Picture Monitor A14 esce e c wae ole ee ar ere Race cs 3 29 Mideo Amplifier oe et ne eret re gina e el rele op ein 3 29 12 Vand tS V SUppli68 oeer e eA ee siete wre er Rn od Seta 3 29 Vertical DeflectlOn eee eid wave tie nieces eine gue
227. erface Interactive diagnostics provide the service person choices to control the tests that run and the manner in which they run In the user interactive mode any or all tests within a group of tests can be selected for execution Diagnostics displays can be routed to one of the instrument serial ports for viewing on a terminal This is useful if a malfunction does not permit the testing progress and results to be displayed on the VM700T CRT A special setting of the boot switch is used to route the diagnostic test displays to the serial ports NOTE Diagnostics can also be controlled and executed remotely through the serial port This method is most useful if the display system is inoperative or in a service environment for programmed troubleshooting of the VM700T Refer to Viewing Diagnostics Remotely on page 6 85 for more information VM700T Video Measurement Set Service Manual 6 55 Troubleshooting Procedures 6 56 During execution diagnostics give positive feedback of progress indicating results as they are gathered During power up execution these results are presented in minimal fashion a test which passes shows only its main result whereas one that fails also shows the sub results that caused the failure During looping and user interactive modes results display options are available to either show only the main test results or all the test results To facilitate quick appraisal of diagnostics results the informa
228. ernal sync connector are loop through connections that must be terminated in 75 when they are not used Three 75 terminations are provided as standard accessories VM700T Video Measurement Set Service Manual 2 17 Operating Information Equipment Video Signal Sources Required Most measurements supported by the measurement set are made using television video signals The video signals can be from either off the air broadcast or looped through programming signals connected to the rear panel Channel and External Sync inputs see Figure 2 11 Non loop through signals must have the signal output terminated with precision 75 Q termination three of which are provided as standard accessories to the VM700T Video Measurement Set You must use an appropriate test signal to test the measurements You can obtain the test signals needed from an appropriate test signal generator In most cases the measurement set needs a video signal in a specific format NTSC or PAL to make a meaningful measurement Waveform mode displays can be of any signal that can be phase locked to the external sync source CH Ho CHAN CHAN EXT BEI Ier i 71 Figure 2 11 Video signal input connectors 2 18 VM700T Video Measurement Set Service Manual Operating Information Connecting Audio Option 40 to a Source Input Connector Pin Assignments The VM700T Audio option comes with two male mini XLR to female XLR adapter cables wired as shown in Figure
229. escriptions Column Column name Description 1 Figure amp index number Items in this section are referenced by figure and index numbers to the exploded view illustrations that follow 2 Tektronix part number Use this part number when ordering replacement parts from Tektronix 3and4 Serial number Column three indicates the serial number at which the part was first effective Column four indicates the serial number at which the part was discontinued No entries indicates the part is good for all serial numbers 5 This indicates the quantity of parts used 6 Name amp description An item name is separated from the description by a colon Because of space limitations an item name may sometimes appear as incomplete Use the U S Federal Catalog handbook H6 1 for further item name identification 7 This indicates the code of the actual manufacturer of the part 8 Mfr part number This indicates the actual manufacturer s or vendor s part number Abbreviations Abbreviations conform to American National Standard ANSI Y1 1 1972 Mfr Code to Manufacturer The table titled Manufacturers Cross Index shows codes names and addresses Cross Index of manufacturers or vendors of components listed in the parts list 10 2 VM700T Video Measurement Set Service Manual Replaceable Mechanical Parts Replaceable parts list Fig amp index number 10 1 1 25 26 27 28 29 30 31 32 33 34 35 36 37 38
230. est Equipment Depot 800 517 8431 99 Washington Street Melrose MA 02176 FAX 781 665 0780 TestEquipmentDepot com Specification Table 1 86 Tektronix automatic audio test measurement specifications Measurement Insertion Gain Error Sweep Gain Min and Max THD N Crosstalk into channel Test Level 6 dBu 0 dBu 6 dBu SNR weighted Test Level 6 dBu 0 dBu 6 dBu ANSI Crosstalk into channel ANSI SNR weighted Test Level 6 dBu 0 dBu 6 dBu Max Compandor Error rise fall Gain Difference Phase Difference Range Accuracy includes flatness 12 dB 0 1 dB lt 0 0396 to 7096 10 1 digit 1 dB lt 66 dB to 0 dB x 60 dB to 0 dB lt 54 dB to 0dB 2 dB 10 dB to 90 dB 10 dB to 90 dB 10 dB to 84 dB 0 to 10 dB 0 2dB 2 dB 10 dB to 90 dB 10 dB to 90 dB 10 dB to 84 dB 12 dB 0 2 dB 180 to 180 1 1 Assumes insertion gain is within 6 dB 2 The measurement range specification assumes that the input level is within 6 dB of the 0 33 test level in the audio configuration The actual 0 33 test level range is 6 dBu to 14 dBu 3 The weighting filter is a 15 kHz sharp cutoff low pass filter Audio Analyzer Specifications Table 1 87 Frequency and Noise specifications Measurement Level Maximum Allowable Input 1 32 Specification Comments 30 dBu 24 5 V rms VM700T Video Measurement Set Service Manual Specification Tab
231. et as shipped from the factory is configured to skip diagnostics at power on for a quicker start up You can run diagnostics at power on by doing an Auto Reset Refer to Auto Reset on page 6 84 for information on forcing an Auto Reset If any of the diagnostic tests fail refer your measurement set to a qualified service person You may want to access the diagnostics for a couple of operating selections These are setting the power on run mode either to run the diagnostics at power on or to skip them for a quick start and calibrating the touch screen VM700T Video Measurement Set Service Manual Operating Information Calibrating the Touch measurement set is shipped from the factory with its touch screen fully Screen calibrated However if you notice misregistration of the touch screen you can recalibrate it Use the following procedure to calibrate the touch screen 1 Switch off power to the measurement set at the front panel 2 Press and hold the Menu button while turning on the power After the measurement set beeps twice to acknowledge the startup mode release the Menu button The measurement set then initializes into the Low Level Diagnostics Interface with the VM700T Startup Menu see Figure 2 2 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection VM700T STARTUP MENU Key Selection Instrument RUN MODES Menu UTILITIES Menu R U D Low Level DIAGNOSTICS Menu
232. et Service Manual Theory of Operation Address Register The normal input to static RAM is the 16 bits from the sequencer address register The four TRIG bits the 16 bit counter CARRY bit and 11 bits out of 32 from the output of static RAM comprise the 16 bit input to the register The TRIG bits are the output of trigger RAM The 11 address bits are the 11 LSBs from the output of the sequencer static RAM that are also fed through an address latch to the dynamic settings static RAM as its normal input nine of these address bits are used in current hardware the other two are reserved for future expansion Static RAM The 32 bit word output of the static RAM memory block goes to a number of circuits when the sequencer is running Eleven bits of the output are fed to an address latch The same 11 bits are also routed to the address register as the program counter Sixteen bits of the output are fed as data to the 16 bit counter while two more bits provide counter control Three other of these bits provide signalling to the acquisition section of the board 16 Bit Counter Sixteen of the 32 bits output by the sequencer static RAM are used as data by the 16 bit counter The two control bits determine the count direction and whether the counter is to be loaded with the 16 data bits or is to hold the current count When the counter overflows the CARRY bit is returned to the address register The CARRY bit can be used to count samples lines f
233. f Ifthe displayed values are within the required limits touch the Accept Data soft key Table 5 5 SDI Eye Diagram application gain and offset value limits Measurement New data value limits Eye circuit gain 1 460 to 1 590 Eye sampler offset 40 000 to 105 000 VM700T Video Measurement Set Service Manual Adjustment Procedure CAUTION The following step requires a 67 5 MHz clock that must meet the specifications listed in Table 5 4 on page 5 22 or you will misadjust the instrument If you are using the BG1 module of the TG2000 Signal Generation Platform as the clock source you must use the Clock Out connector on the BG1 module or you will misadjust the instrument 2 Perform the following steps to adjust the SDI Jitter application b Touch the Jitter soft key Connect a 67 5 MHz clock to the VM700T SDI Ch A input Terminate the SDI Ch A loopthrough using 75 Q high frequency terminator Touch the Calibrate soft key Touch the Proceed soft key once to perform the Jitter Scale Factors adjustment Wait until the message at the bottom of the screen disappears Touch the Proceed soft key a second time to perform the Jitter Offset adjustment Check that the displayed New Data values are within the limits shown in Table 5 6 If the displayed values are within the required limits touch the Accept Data soft key Remove the signal cable from the SDI Ch A input Table 5 6 Jitter application adj
234. f the reference level stored in step 5 Change the TV standard parameter to PAL by pressing the XY Arrow hard key Change the leveled sine wave generator frequency to 4 43 MHz but do not change the output level setting Let the display stabilize Adjust the Chroma Filter Flatness adjust so that the change in amplitude Delta Amp is within 0 02 of the reference level stored in step 4 Disconnect the cables and test equipment from the VM700T VM700T Video Measurement Set Service Manual Adjustment Procedure Adjust ADC Gain ADC gain is auto calibrated during normal VM700T operation This check and adjustment should only be done as part of a board exchange repair to set the adjustment to a nominal setting for auto calibration Test Equipment Required m Non metallic flat blade adjusting tool Tektronix part number 003 1364 00 Adjusting ADC Gain l Press the Measure key then the Diags and the ADC Gain Adjust soft keys 2 The VM700T should display 100 3 NOTE If the VM700T meets the limits described skip step 3 Adjusting the VM700T unnecessarily for example to get a better reading on a calibration result that is within limits can introduce errors into a functional instrument 3 Ifthe number displayed is outside the tolerance range remove the top cover of the VM700T and carefully adjust R21 ADC Gain on the ADC board to bring the number to 100 See Figure 5 1 on page 5 5 for the adjustm
235. faulty module for shipment Ship the faulty module to Tektronix Inc Customer Service Materials M S 58 185 PO Box 500 Beaverton Oregon 97077 0500 Tektronix charges a standard fee for each out of warranty module exchanged This fee will be quoted when you request the exchange module If the faulty module is not received at the above address within 30 days of your request of an operating exchange module the full catalog price of the module will be invoiced If your module has been damaged or modified in any of the following ways it is not eligible for exchange m The module is damaged during repair attempts by personnel other than Tektronix Representatives The module is damaged through improper use or connection to incompatible equipment m The module has been modified by the customer The module has been modified to the customer s specifications by Tektronix In these cases Tektronix invoices the full catalog price of a replacement module Call your local Tektronix field office for further information Customer Service Outside the U S Customers outside the United States should contact their local Tektronix sales subsidiary or distributor for details on servicing the VM700T VM700T Video Measurement Set Service Manual 6 3 Maintenance Inspection and Cleaning 6 4 A Cleaning CAUTION Cleaning and general maintenance of the VM700T should be performed only when the instrument is powered off and the power
236. formance Verification Measuring the Burst Frequency 26 Disconnect the test equipment from the measurement set NOTE If the response on channel A is out of limits go to Adjusting Filter Flatness on page 5 6 in the Adjustment Procedure section of this manual If either channel B or channel C does not pass but channel A does the Analog input board may need replacement Check with your nearest Tektronix represen tative or factory service for assistance and board replacement information This procedure checks the calibration of the internal oscillator using a signal source of known frequency NOTE To successfully run this procedure the internal oscillator of the measure ment set must be completely stable Power on the measurement set at least 20 minutes before performing this procedure Test Equipment Required m Television signal generator with full field and burst capability accurate to 1 Hz Tektronix TSG 170A or equivalent Coaxial cable 75 Q high quality noise free 1 meter length Tektronix 012 0074 00 Termination 75 Q precision BNC Tektronix 011 0102 01 or equivalent Specification Checked Burst frequency accurate to 10 Hz using the internal frequency reference NOTE The frequency of the signal generator used must be accurate to 1 Hz to ensure a valid limit check reference on the burst frequency measurement Procedure Measuring the Burst Frequency 1 Disconnect all signal inputs
237. front panel controls shown in Figure 2 8 consists of a touch screen interface and a 20 button keypad with a control knob Tektronix 700 turbo Waveform Vector Picture Measure Auto volts JTRE FIX 1 gus i 1 SOURCE 1 1 Freeze A B Average Help Configure Function Copy Select Line O Move O Expand s s APL 49 9 Precision Mode Off 525 line NTSC No Filtering Synchronous Sync Source Slow clamp to 0 00 V at 6 63 uS Frames selected 1 2 1H Cursors Sync Noise Extra Filter Clamp 1 15 05 dB Functions seiect Couple Display Graticule PISFAR POWER OVER TEMP o o O E Intensity nd 1 i Figure 2 8 The VM700T Video Measurement Set front panel Touch Screen The display CRT area of the measurement set has a touch screen interface for communicating with the measurement set You touch the soft keys on the screen to select and control many operations of a running application When applicable you can change selection values within a soft key by rotating the large control knob You also use the touch screen interface to edit the configuration files that control the operation of the measurement set The place you touch the screen is also the zoom point for expanding or contracting a displayed waveform VM700T Video Measurement Set Service Manual 2 11 Operating Information
238. g Procedures The troubleshooting material provided in this section is general and is not intended to cover specific instrument malfunctions This section contains the following subsections Troubleshooting techniques page 6 50 Isolating operational faults page 6 51 m Diagnostics page 6 55 m Low level diagnostics page 6 59 m Diagnostic utilities page 6 65 m Calibrating the touch screen page 6 68 m Setting the power up mode page 6 70 m VM 700T boot switch and diagnostic LED page 6 73 m Running the high level diagnostics page 6 74 Auto reset running all diagnostics page 6 84 m Viewing stored diagnostic information page 6 84 m Viewing diagnostics remotely page 6 85 m Troubleshooting the power supply and the CRT display page 6 90 m Troubleshooting Option 40 and Option 41 Audio page 6 95 m Troubleshooting Option 48 GPIB page 6 99 m Troubleshooting Option 1S SDD page 6 100 More Information The following useful troubleshooting information can be found elsewhere in this manual m Refer to Theory of Operation on page 3 1 for descriptions of the electrical operation of the VM700T Video Measurement Set from a functional circuit block perspective m Refer to Diagrams on page 9 1 for an instrument level block diagram and interconnection diagram m Refer to Replaceable Mechanical Parts on page 10 1 for the list of replaceable parts accompanied by exploded view drawings of the instrument VM700T Video Measurement Set Service Manu
239. g for correct operation after each replacement until you have located and replaced the faulty module Interconnecting Cables Signals and power supply voltages are passed through the instrument by a system of interconnecting cables The connector holders on these cables have numbers that identify terminal connectors A triangular key symbol is used to identify pin 1 on the circuit board to assist in aligning the correct pins on the mating connector Isolating Operational Faults This section presents a series of operational fault symptoms and suggests corrective actions The most efficient way to use the information involves a two step approach 1 Compare the failure symptoms you are experiencing with the symptoms presented in Table 6 3 2 Runthe VM700T built in diagnostics routines to assist in isolating the failure Following these steps will assist you in isolating any VM700T fault to a field replaceable module such as a circuit board For information on how to return defective instrument modules to Tektronix for repair refer to Customer Service on page 6 3 Table 6 3 lists a series of instrument faults or failures related possible causes and suggested corrective actions Run the complete set of diagnostic test to determine if suspected modules pass or fail the testing before attempting any module exchanges You can use the information in the table along with the results of the diagnostic tests to characterize faulty VM700T ope
240. g the Line Voltage Range and Fuse 6 44 When unpackaging the VM700T Video Measurement Set for installation keep the shipping carton and packaging material If returning the VM700T for repairs should become necessary you will then have packaging available that will provide adequate protection for shipment The VM700T will operate with line frequencies of 50 Hz or 60 Hz over two line voltage ranges The low voltage range is from 90 VAC to 132 VAC 115 VAC nominal The high voltage range is from 180 VAC to 250 VAC 230 VAC nominal WARNING For your protection and to avoid damage to the measurement set shut the power off before removing or replacing any circuit boards connectors or jumpers The voltage range selection switch and fuse holder are located on the lower left corner of the rear panel of the VM700T The VM700T is shipped from the factory set for 115 VAC operation If this setting must be changed to 230 VAC simply set the voltage range selection switch to the 230 V position to operate in the high voltage range The 6 A slow blow fuse provides the proper protection in the low voltage range and must be replaced with a 3 A slow blow fuse for operation in the high voltage range NOTE If you wish to use Password protection for your user definable configura tion DIP switch settings on the A5 CPU board must be changed Refer to the VM700T Option 01 NTSC and Option 11 PAL User Manual Configuring the VM700T for a deta
241. ge For missing supply voltage information on how to return defective instrument modules to Tektronix for repair see Exchanging VM700T Modules Check that all the green Supply LED Turn the master ON OFF switch off and back on to recycle indicators are off except the VH LED The the power supply shutdown control circuitry Check that the supply will be in shutdown mode power supply operates normally after power is reapplied and the front panel STBY ON switch is turned on If not replace the power supply Check Supply LED indicators to see ifan Turn off the master ON OFF switch and let the VM700T over temperature shutdown has occurred cool down before restarting the power When the power The green LED indicators for the supply will comes back on check that the fan operates and that the be on if a shutdown has not yet occurred power supply operates correctly Check that the fan i rating Check the air filters in the instrument s front bezel If they Over temperature shutdown of the supply become clogged the lack of air flow may cause will occur at about 10 C over the warning overheating Use a mini vacuum cleaner to remove the temperature At that point all the green dust from the filters For more information on cleaning the power supply indicators except the VH LED front bezel air filters see Cleaning the Touch Screen and will be off Front Bezel Air Filters Check for flashing supply LED indicators Check f
242. ge hardkey light is lit When the display stabilizes press the Freeze hardkey The Delta Amp reading should remain at 0 If the Delta Amp reading changes press the Freeze key again as many times as needed until the Delta Amp reading remains at 0 This is now the reference to which all other measurements are compared 5 Set the leveled sine wave generator for a frequency of 4 43 MHz do not change the output level 6 To speed up the response to the frequency change toggle the Average hardkey off then back on again after the display has re stabilized 7 Check that the amplitude is within 0 546 Delta Amp of 0 5 or less of the 50 kHz reference level stored in step 4 8 Setthe leveled sine wave generator for 5 8 MHz do not change the output level VM700T Video Measurement Set Service Manual Performance Verification 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Again to speed up the response to the frequency change toggle the Average hardkey off then back on again after the display has re stabilized Check that the amplitude is within 0 55 of the reference level stored in step 4 Change the TV Standard parameter from PAL to NTSC by pressing the XY Arrow hardkey Change the filter selection from No Filter to the NTSC bandwidth limiting filter by pressing the Move Expand hardkey until the filter displays NTSC BW Lim Return the leveled sine wave gener
243. haracteristics Amplitude Range Table 1 109 AES Audio Input Characteristic Electrical Characteristics Input type Return Loss Signal Characteristics Amplitude Range Format Performance requirement Supplemental information BNC 75 Q compensated z 25 dB 1 MHz to 360 MHz Channel on or off z 15 dB 1 MHz to 360 MHz 800 MVp p 10 400 ps to 800 ps Performance requirement Supplemental information BNC passive loopthrough 75 lt compensated gt 30 dB 50 kHz to 6 MHz Power on or off 6 dB with respect to 1 Vp p video Performance requirement Supplemental information BNC 75 gt 15 dB 0 1 MHz to 6 MHz 0 2 Vp p to 2 Vp p AES EBU digital audio per AES3 1992 ANSI S4 40 1992 Table 1 110 Environmental specification Characteristic Maximum operating temperature 1 44 Performance requirement Supplemental information VM700T with Option 15 installed VM700T Video Measurement Set Service Manual CET Operating Information Installation Unpackaging Power Requirements A The VM700T Video Measurement Set is a multi function television test and measurement device with an easy to use interface The measurement set performs the functions of a waveform monitor vectorscope automatic measurement set and a noise measurement set on acquired television signals The measurement set does measurements on video signals obtained from either live TV signals broadcast or cable or television test equipm
244. he Analog Ref input Check for a video signal on J5 pin 8 on the SDI board Leave the J5 cable installed and probe the board from the bottom as shown in Figure 6 65 If the video signal is present on J5 pin 8 replace the SDI board If the video signal is not present remove the SDI Rear Panel Interface assembly Disconnect the flat cable from the SDI Rear Panel Interface assembly and then check each of the 10 wires in the cable for continuity If the cable is good replace the SDI Rear Panel Interface assembly No Signal From the Perform the following steps when the AES EBU Digital Audio input does not AES EBU Digital Audio operate Input 2 3 4 1 Connect AES EBU digital audio signal to Option 1S Check for an audio signal on J5 pin 2 of the SDI board see Figure 6 65 If the audio signal is present on J5 pin 2 replace the SDI board If the audio signal is not present remove the SDI Rear Panel Interface assembly Disconnect the flat cable from the SDI Rear Panel Interface assembly and then check each of the 10 wires in the cable for continuity If the cable is good replace the SDI Rear Panel Interface assembly No Signal From the Perform the following steps when the LTC Time Code input does not operate LTC Time Code Input 2 1 Connect a time code signal to Option 1S Check for a time code signal on J5 pins 4 and 5 of the SDI board see Figure 6 65 If the time code signal is present on J5
245. he cooling fan a Remove the power supply module refer to Power Supply Module on page 6 38 b With cutters remove the plastic retainers holding the fan wire harness to the bottom of the left card cage c Disconnect the VGA circuit board connector and separate the intercon nection cable from the fan housing VM700T Video Measurement Set Service Manual 6 41 Maintenance d Remove the screws and nuts holding the cooling fan and separate the fan and its finger guard SN B029999 and below only or its EMI filter SN B030100 and above only or if Option 1S installed from the back panel See Figure 6 26 NOTE Remove the two screws accessible from the bottom first Then turn the instrument right side up remove the remaining two screws and carefully lift the fan clear of the instrument EMI fan filter bow SN B030100 and above only Blank panel removed gt for access to separate fan nut Fan finger guard SN B029999 and below only IN 26 l ia VGA A21 board removed for access to separate fan nut Figure 6 26 Removing the cooling fan 2 Replace the cooling fan by performing step 1 in reverse order CAUTION Incorrect installation of the fan assembly will result in overheating and possible damage to the measurement set 6 42 VM700T Video Measurement Set Service Manual Maintenance NOTE Reinstall plastic retainers to hold the f
246. he filter switch board it has no connectors for mounting a filter In place of a filter a resistor network provides a small amount of signal attenuation The loss of each filter in slots 1 5 is adjusted to match the loss from the resistance in slot 0 Slots 1 5 accommodate the five plug in filters The only filter with controllable parameters is the low frequency noise filter The 3 dB point on this filter can be set to 1 KHz 7 5 kHz 10 kHz or 15 kHz The output amplifier provides the 75 drive needed for the input to the analog input board When the acquisition controller board asserts FIL3 the output amplifier switches from unity gain to a gain of eight VM700T Video Measurement Set Service Manual Theory of Operation 1X 8X SELECT TUTTA TU AT FILTER SLOTY To From SELECT amp Acquisition CONTROL Video to Controller Analog Input Board Y yY X ourPUTAMpL 50819 CEP C CASCO ERO NEN J CES SS STS SS SS a ee 7 SLOT 1 alo lt Y o E BE c FILTER lt o 2 H o o z as es J VS SS SS Lc 4 cy SLOT2 Y FILTER P eer J RS See l SLOT 3 Y Y Video from gt Analog Input FILTER lt lt Board EE J r E ES 7
247. he first of 256 locations in the EEPROM The first test checks for this and fails if some other number is found in the first location Thus a failure of this test indicates that the board was never calibrated since the EEPROM was installed or replaced The second test reads the entire data block and computes a CRC on all but the last 32 bits which contains the reference CRC The computed CRC is compared against the reference CRC and the test fails if there is a mismatch VM700T Video Measurement Set Service Manual 6 107 Troubleshooting Procedures Table 6 13 SDI Option 1S diagnostic test descriptions Cont Test name SDI Ctrl Regs Ctrl Register 0 4 Ch AJB Rate Bits Ch A Manual Rate Ch A Auto Rate Ch A Rate Xcheck Ch B Manual Rate Ch B Auto Rate Ch B Rate Xcheck AJD Converter Voltmeter Inputs Cal DAC Wraparound 6 108 Description There are 5 control registers 0 4 and one status register on the SDI board All are 32 bits in size and all are readable and writable The correlation between these registers and devices on the board is as follows Control Register 0 LS 16 bits 049 MS 16 bits 050 Control Register 1 LS 16 bits U47 MS 16 bits U48 Control Register 2 LS 16 bits U51 MS 16 bits U52 Control Register 3 LS 16 bits U56 MS 16 bits U53 Control Register 4 LS 16 bits U54 MS 16 bits U55 Status Register LS 16 bits U57 MS 16 bits 058 Each control register is subje
248. iagnostics CONFIGURATION Menu Diagnostics HELP Menu Calibrate TOUCH PANEL INTERFACE c ux Reprint Q Abort Menu Input your selection Figure 5 8 VM700T startup menu 4 Press the Select Line button to display the Run Mode Menu shown in Figure 5 9 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection INSTRUMENT RUN MODES MENU The instrument will be reset to run in the mode selected below overriding current boot switch settings Key Selection N NORMAL POWERUP Start Instrument in Powerup Mode Current Powerup Mode is QUICK START abort this menu and go to the DIAGNOSTICS CONFIGURATION MENU to change it P POWERUP 5 Do Diagnostics start Instrument Q QUICK Skip Diagnostics start Instrument L LOW LEVEL DIAGS LOOP Loop on Low Level Diagnostics D HIGH LEVEL DEBUG Start Instrument in HL Debug Mode A 5 Do EXTRA Diagnostics start Instrument Reprint Q Abort Menu Input your selection Figure 5 9 Instrument run modes menu VM700T Video Measurement Set Service Manual 5 21 Adjustment Procedure 5 Inthe Run Modes Menu use the large control knob to select A Auto Reset and press the Select Line button to activate the selection This restarts the VM700T and runs the full set
249. ideo Measurement Set Service Manual Maintenance Servicing Preparation A Preventive maintenance consists of cleaning visual inspection performance verification and if needed readjustment The preventive maintenance schedule established for the instrument should be based on its environment and the amount of use Under average conditions preventive maintenance should be performed every 12 months of operation NOTE If the instrument does not function properly troubleshooting and corrective measures should be taken immediately to prevent additional problems If the instrument fails during the warranty period contact your local Tektronix representative No user repair should be attempted during the warranty period This section contains the following information W Servicing preparation page 6 1 W Inspection and cleaning page 6 4 m Repackaging the instrument page 6 5 m Removal replacement instructions page 6 6 m VM 700T rack mounting instructions page 6 44 Troubleshooting procedures page 6 49 CAUTION The following procedures should be performed only by qualified service personnel Performing these procedures incorrectly could result in damage to the instrument Before you begin to service this instrument perform the following steps m Read the General Safety Summary and the Service Safety Summary at the front of this manual m Read the Operating Information section of this manual m Read the Preventing El
250. ideo Measurement Set Service Manual Specification Table 1 74 RS 170A vertical blanking interval Measurement Range Test signal Equalizing Pulse Width Vertical Blanking Serration Width Vertical Blanking Vertical Blanking Width Vertical Blanking Table 1 75 FCC horizontal blanking interval timing Measurement Test signal Breezeway Width Horizontal Blanking Color Burst Width Horizontal Blanking Front Porch Duration Horizontal Blanking Horizontal Blanking Width Horizontal Blanking Horizontal Sync Rise and Fall Time 80 ns to 120 ns 10 ns to 30 ns Horizontal Blanking 120 ns to 300 ns 20 ns 300 ns to 1 0 us 30 ns Horizontal Sync Width 1 us to 8 us Horizontal Blanking Sync to Setup 5 usto 18 us Horizontal Blanking Sync to End of Burst 6 usto 15 us Horizontal Blanking Table 1 76 FCC vertical blanking interval timing Measurement Range Accuracy Test signal Equalizing Pulse Width 25 to 100 of nominal 0 3 Vertical Blanking horizontal sync pulse width Serration Width 1 us to 20 us Vertical Blanking Vertical Blanking Width 19 lines to 29 lines 0 1 lines to 0 2 lines Vertical Blanking Table 1 77 Amplitude and Phase measurements Average Picture Level APL Full Field Bar Amplitude FCC NTC 7 Composite Chrominance to Luminance 300 ns 5 ns FCC NTC 7 Composite Delay Relative Chroma Time Chrominance to Luminance 0 to 16096 1 7 Composite Gain Relative Chroma Level Differ
251. ideo signals You must use the SDI Ch A input to perform electrical signal measurements in the following applications SDI Eye Diagram SDI Jitter and SDI Wander The remaining loopthrough connector must be precision terminated in 75 9 when not used in a loopthrough mode The primary function intended for this input is to measure a signal under test The SDI Ch B input is an internally precision terminated 75 2 BNC input for serial digital video signals The SDI Ch B input cannot perform the electrical measurements in the following applications SDI Eye Diagram SDI Jitter and SDI Wander Although you can use this input to measure a signal under test the primary function intended for this input is to enable you to use a digital reference signal to make comparative timing measure ments with the signal under test on the SDI Ch A input The Analog Ref input is a loopthrough BNC input for an analog timing reference signal black burst The remaining loopthrough connector must be terminated in 75 Q when not used in a loopthrough mode The only function intended for this input is to enable you to compare your analog timing reference signal with a digital timing reference and or a signal under test The timing comparison between an analog reference signal and a serial digital signal will never be a perfect match however you will be able to see resolution to within 1 us The SDI Output is a buffered BNC monitor output that can be set to ou
252. ied with VM700T Option 40 For level accuracy level flat ness frequency and phase measurement accuracy proce dures In distortion measurement procedure connects two sine wave generators to one Op tion 40 input In frequency and phase mea surement accuracy procedure used to apply signal from one sine wave generator to both Option 40 inputs Used to connect the sine wave generator to the triple VM700T audio inputs of Option 41 TEGAM SG5010 two are needed to check distortion measurement accuracy E Z Hook 5023 or equivalent Supplied with Option 40 Fabricated by user Fabricated by user Fabricated by user a DB 37 connector is included with Option 41 1 The TEGAM SG5010 sine wave generator requires a TEGAM TM500 or T5000 series power module NOTE Before performing the level accuracy procedure Verify the sine wave generator level at 120 Hz by measuring with an accurate AC voltmeter such as a HP 3458A Digital Voltmeter You may also use an AC voltage calibrator such as Fluke 5700A for this measurement Verify that the sine wave generator can meet the amplitude accuracy specifications listed in Table 4 2 VM700T Video Measurement Set Service Manual ae Audio Option 40 Verification Procedure Use the following procedures to check the Option 40 Audio Option Check Level Measurement Accuracy and Flatness Specifications Checked Option 40 Level Accuracy and Flatness Thi
253. iled description of how Password operates VM700T Video Measurement Set Service Manual Maintenance Rack Mounting VM700T fits in a standard 19 inch rack and is shipped with the necessary hardware for rack mounting Spacing between the front rails of the rack must be at least 17 3 4 inches to allow clearance for the rack slides Rack slides conveniently mount in any rack that has a front to rear rail spacing between 15 1 2 and 28 inches Six inches of clearance between the rear panel of the VM700T and the rear rack panel is required for connector space and to provide adequate air circulation The rack slides consist of two assemblies one for each side of the rack Each assembly consists of three sections as shown in Figure 6 27 The stationary section of each rack slide attaches to the rack rails The chassis section mounts on the VM700T and is installed at the factory The chassis section slides into the intermediate section which in turn slides into the stationary section Automatic latch 10 32 PHS 10 32 PHS screws screws Rear a mounting VES 2 ER 2 v 2 S Automatic latch n 10 32 PHS Screws Chassis section Bar nuts Stationary section ele ES Intermediate section j S Stop latch hole Figure 6 27 Construction of rack slides VM700T Video Measurement Set Service Manual 6 45 Test Equipment Depot 800 517 8431 99 Washington Street Melrose MA 02176
254. ing measures variation in camera output luminance levels when light input is constant CCD or tube cameras Vertical Smear measures the camera s ability to handle excess light CCD cameras only Option 30 Component of the VM700T Video Measurement Set gives you access to the following 12 measurements Bowtie measures timing and amplitude differences Channel Delay measures timing and amplitude differences as does Bowtie but it works with signals containing jitter m ColorBar measures the Y Pb and Pr amplitudes of each chroma packet m Factor measures K 2T K 5T and Pulse to Bar ratio on component input signals m Level Meter monitors peak to peak amplitude of a component signal m Lightning displays two XY graphs on the screen Luminance NonLinearity measures luminance nonlinear distortion Component Multiburst measures frequency response Noise Spectrum measures noise level and performs spectrum analysis m Overlay displays stacked or superimposed Y Pb and Pr component inputs Parade displays side by side Y Pb and Pr component inputs Vector provides an XY display of the Pb and Pr components VM700T Video Measurement Set Service Manual Options Audio Video Timing Measurement Option 42 The Audio Video Timing measurement option Option 42 of the VM700T is part of a system that measures the timing difference between audio and video portions of a program that arrive from different tr
255. into a power source outlet that has a properly grounded protective ground contact Measurement sets are shipped with the power cord required for the country of destination Refer to the Options section for information on the available power cord options European power cord options A1 and A2 require an additional accessory for operation in the EU countries When the VM700T Video Measurement Set is ordered with either the A1 or the A2 power cord option the VM700T Power Line Conditioning accessory is also provided The Power Line Conditioner accessory to the VM700T assures that the VM700T meets the Line Harmonics requirements of the European Union when operated from a 230 Vac mains source The line conditioner is for use only with the VM700T when operating the VM700T from a 230 Vac mains source The Power Line Conditioner provides no benefit when the VM700T is operated from a 120 Vac mains source and should NOT be used NOTE The VM700T will not be damaged if operated from a 230 Vac mains source without the Power Line Conditioner connected to the power input VM700T Video Measurement Set Service Manual Operating Information Installing the Power Line Power Line Conditioner can be used with either with a rackmounted Conditioner VM700T or a standalone VM700T on a benchtop Rackmounted VM700T Use the mounting bracket and screws provided with the accessory to attach the box to a rackmount rail Use only 10 screws for the
256. ion signals Input commons are connected together at the input and applied to the input to the Audio Analog board Filters provide some protection to the Audio Analog board from electromagnetic interference that may accompany the input signal VM700T Video Measurement Set Service Manual 3 43 Theory of Operation Option 48 GPIB Interface Board A19 Figure 3 17 shows the installed location of the A19 circuit board in a fully optioned instrument The GPIB Interface Board A19 contains a GPIB processor a GPIB controller Dual Port RAM and additional circuity to handle communication between the GPIB processor and the VM700T processor and communicate with remote devices through the GPIB bus Figure 3 18 shows the functional blocks and bus interconnections of the GPIB board 000000000000 A19 GPIB gt gt Front Interface board Right side of the measurement set Figure 3 17 GPIB board location in the measurement set The GPIB processor tracks the state of the GPIB handles attention messages and performs protocol conversions It is a separate processor that is loosely coupled to the main processor in the VM700T by interrupts and shared memory The shared memory and the interprocessor communications register IPC register are accessible by either processor and are u
257. is driven by an ECL source that is capacitively coupled to the clock input The TTL level outputs of the A D converter are divided down to ECL levels through a resistive divider network and applied to buffers A 1 3 V reference for the ECL buffer amplifiers is derived from the A D converter s balanced power supply The buffer is composed of 12 ECL buffers one for each output line from the A D converter They are located close to the A D Converter to minimize loading on the converter outputs and unclocked to minimize delays The output latch supplies differential drive for the cable transporting the data to the acquisition controller The latch is set and reset by ASYNC SET and ASYNC RESET from the acquisition controller board It is clocked by the OUT LATCH clock derived from the 4FSC signal VM700T Video Measurement Set Service Manual 3 11 Theory of Operation e FLATNESS ADJUST SIGNAL CONDITIONING AMPL e 42 5 V and 2 5 V REGULATORS COMP ANALOG ADC IN TEST POINT SIGNAL IN GAIN SIGNAL IN DiS v SIGNAL CONDITIONING AND REGULATORS CONDITIONED ANALOG SIGNAL es ee ee ep i amu ce m me a ee a v me c 71 VREF OUTPUT SAMPLE CLK BUFFERS H ADC LATCH D0 D9 CKD SAMPLE CLK is ben UE Lu asi esi
258. is grounded and the other two lines are connected to circuitry on the front panel board that decodes the knob s output Push Buttons The front panel push buttons are momentary contact single pole single throw switches divided into two groups of eight and one group of four The push buttons drive three 8 bit buffers which are read by the front panel processor enabled by KEY 0 2 Firmware provides contact debouncing LEDs The front panel LEDs are driven by three 8 bit latches The front panel processor writes bit patterns into the latches turning on the appropriate LED KEY o Push Buttons KEY KEY Push Buttons FPD 0 7 To From Front Panel Reset Board Figure 3 11 Keypad board 10 2 block diagram 3 28 VM700T Video Measurement Set Service Manual Theory of Operation Main Interconnect Board Left and Right 11 Picture Monitor A14 Video Amplifier 12 V and 5 V Supplies Vertical Deflection The VM700T has both attached assemblies and plug in modules The plug in modules are supplied with power data address and control signals through the interconnections to the Main Interconnect Board There is a Left and Right board for the plug in modules on the left and right sides of the VM700T and an interconnect board that ties the two sides together The Picture Monitor produces the visual display of the VM700T It is has vertical and ho
259. ister It may be disabled set to the default frequency or set to either 921 kHz or 460 8 kHz Connector connector circuitry provides a 32 bit address bus buffer and a 32 bit data bus buffer Addresses are unidirectional The data buffer is bidirectional to handle data both to and from the CPU I O board These busses are connected to the system bus for interconnection to the CPU VM700T Video Measurement Set Service Manual 3 19 Theory of Operation Data Acquisition Controller Board 18 3 20 Video Data and Clock Inputs FIFO Demultiplexor Acquisition Control Acquisition Clock Data Bus Interface Data Acquisition Memory Static RAM Min Max ASIC The combined Data Acquisition Controller board A18 does both data acquisi tions and controlling of the acquisition process The acquisition portion of the board is a programmable data interface between the ADC board and the CPU microprocessor The controller state machine can be programmed to recognize data sequences and generate signals to the data acquisition section telling it when to perform various tasks Figure 3 7 shows a block diagram of the data acquisition section of the Acquisition Controller board Data from the ADC board enters the Acquisition Controller board through a 34 pin connector The inputs are differential ECL levels terminated by 100 resistors ASYNC SET and SYNC RESET are outputs controlling the ADC board The FIFO first in first out
260. itudes 20 dBu for example 18 8 2 and 12 dBu and verify that the level accuracy is 0 1 dB 5 Select at least 6 frequencies and 10 amplitudes to test The frequencies and amplitudes you select must be in the ranges listed in Table 4 5 use a signal amplitude level of 70 dBu to test for worst case Table 4 6 shows an example selection of test frequencies and amplitudes 6 Setthe sine wave generator for each of the selected frequencies and amplitudes a Record the level of each frequency b Verify that the measured levels recorded for each frequency are within the flatness specification given in Table 4 3 on page 4 15 Table 4 6 Example test signals for level and flatness test Frequency Amplitudes 30 Hz 10 dBu 21 dBu 40 dBu 49 dBu 100 Hz 51 dBu 55 dBu 59 dBu 1kHz 61 dBu 65 dBu 70 dBu 5 kHz 12 kHz 20 kHz 7 Repeat step 5 for channels B and C VM700T Video Measurement Set Service Manual 4 21 Audio Option 41 Triple Input Verification Procedure Check Distortion and Distortion Measurement Accuracy This procedure verifies that residual THD N is lt 0 03 then checks the THD N measurement accuracy by reading a known signal Specification Checked THD N accuracy is 10 of the reading 1 digit for harmonics at input levels of 20 dBu and greater in a 33 Hz to 22 kHz bandwidth Option 41 Distortion 1 Check residual THD N Measurement Accurac y a
261. ix part number 012 0074 00 Adjusting Filter Flatness 1 Set the leveled sine wave generator for 50 kHz at 500 mV into 75 Q NOTE If the example leveled sine wave generator is being used the output level is set to 3 81 dBm 2 Connect channel A of the VM700T to the leveled sine wave generator and terminate the channel A loop through output connection in 75 VM700T Video Measurement Set Service Manual Adjustment Procedure 3 Press the Measure hard key and move to the VM700T Diagnostics directory by pressing the Diags soft key if necessary In the Diagnostics directory run the sine wave measurement application by pressing the Measure Sinewave soft key 4 Once the measurement application has initialized turn averaging on by pressing the Average hard key until the Average hard key light is on When the display stabilizes press the Freeze hard key The Delta Amp reading should remain at 0 If the Delta Amp reading changes press the Freeze key again as many times as needed until the Delta Amp reading remains at 0 This is now the reference to which all other measurements are compared 5 Set the leveled sine wave generator for 4 43 MHz do not change the output level setting 6 To speed up the response to the frequency change toggle the Average hard key off then back on again after the display has re stabilized 7 Check that the change in amplitude is within 0 5 of the 50 kHz reference level stored in step
262. k Nonoperating Transportation Humidity Operating Nonoperating VM700T Video Measurement Set Service Manual Performance requirement 10 Hz 55 Hz 0 015 inch peak to peak 15 minutes total cycling time per axis for three axes followed by a 10 minute dwell at the identified resonance frequency or at 33 Hz if none is found 50 95 1 2 sine 11 ms duration 3 shocks per surface 18 shocks Qualified under NTSB Test Procedure 1A Category II 30 inch drop Up to 95 at or below 50 C Up to 95 at or below 60 C 1 5 Specification Table 1 7 Certifications and compliances Category Description EC Declaration of Meets intent of Directive 89 336 EEC for Electromagnetic Compatibility and Low Voltage Directive 73 23 ECC Conformity for Product Safety Compliance was demonstrated to the following specifications as listed in the Official Journal of the European Communities EN 55103 Environment Part 1 EN 55022 EN 55103 1 Annex A EN 55103 1 Annex B EN 61000 3 2 Part 2 IEC 61000 4 2 IEC 61000 4 3 IEC 61000 4 4 IEC 61000 4 5 IEC 61000 4 6 IEC 61000 4 11 EN 55103 2 Annex A EN 55103 2 Annex B Product family standard for audio video audio visual and entertainment lighting control apparatus for professional use E2 commercial and light industrial Emissions Class B Radiated and Conducted Emissions Radiated magnetic field emissions Inrush Current AC Power Line Harmonic Emissions Immunity
263. l W load custom six bit dither value Figure 3 9 shows the pre defined dither waveform sequence built into the dither generator Figure 3 9 Dither generator 64 step dither waveform When the dynamic settings address buffer is enabled the CPU microprocessor can read or write the dynamic settings static RAM from the dynamic settings data buffer This can occur while the sequencer is running Addresses for the CPU accesses are buffered The CPU microprocessor can be given access to the dynamic settings static RAM or the static RAM addresses may be connected to the 11 bit output from the sequencer address latch The 11 bit output from the sequencer allows for different dynamic output settings for each step of the sequencer program The 32 bits of output latches are divided as follows eight offset bits eight gain bits eight bits to drive a dither generator m three bits of input selection control m the CPHASE bit inverts the clock phase on the genlock board to allow sampling midway between previous samples W four bits control filter selection on the A4 filter switch board Microprocessor access is also a multiplexed operation A DSACK generator provides the rapid signal generation needed for a minimal number of CPU wait states This DSACK generator is much faster than the DSACK generator in the interrupt controller VM700T Video Measurement Set Service Manual Theory of Operation Front Panel Board A10A1 The fro
264. l digital test signal source module Coaxial cable BNC 3 75 impedance Belden 8281 1 meter Signal interconnections Tektronix part number connectors length 012 0159 00 Terminations 75 Q precision high frequency 26 dB to Signal termination Tektronix part number 300 MHz BNC connectors 011 0163 00 50 Q precision SMA connectors Signal termination Tektronix part number 015 1022 00 50 Q feedthrough BNC connectors Checking the Analog Ref Tektronix part number input 011 0049 01 2 75 Q feedthrough BNC connectors Checking the Analog Ref Tektronix part number input 011 0055 01 SMA to BNC adapter SMA female to BNC male Tektronix part number 015 0572 00 50 Q 75 Q converter 50 Q BNC female to 75 BNC male Tektronix part number 011 0057 01 1 The example leveled sine wave generator requires a TEGAM TM500 or TM5000 series power module VM700T Video Measurement Set Service Manual Tektronix TG 2000 Signal Generation Platform BG1 4 25 SDI Option 1S Verification Procedure Preliminary Setup Perform the following steps to setup the equipment for the Option 1S perfor mance verification 1 Connect power to the VM700T and turn the instrument on Verify that the instrument passes all diagnostics as the instrument powers up 2 Press the VM700T front panel Configure button Select Mode Digital if necessary using the Mode soft key NOTE The VM700T must be set to Mode Digital before you can perform the Option
265. l specifications Characteristic Description Construction Plug in circuit board Designed for installation in the VM700T left side card cage Multilayer ECB material FR4 Dimensions Length 11 inches 279 4 mm includes board retainer Width 7 785 inches 200 mm includes VM700T connector Height 1 plug in unit high 15 16 inch 23 8 mm Shipping Weight Approximately 4 Ib includes GPIB board manual and packing materials Table 1 98 Optional accessories Item GPIB Cable Description 1 m double shielded Tektronix Part No 012 0991 01 2 m double shielded Tektronix Part No 012 0991 00 3 m double shielded Tektronix Part No 012 0991 02 GURU 11 GPIB User s Resource Utility for the IBM Personal Computer Software and manual plus National PC2A GPIB controller board and GPIB cable Tektronix Product No S3FG100 Option 1S SDI Specification The specifications for Option 1S are the same as those listed for the VM700T Video Measurement Set except where listed below The following specifications are only valid when Option 1S is installed in a VM700T Table 1 99 SDI Eye Diagram application Characteristic Performance requirement Supplemental information Eye Diagram Measurements Measurements performed on SDI Ch A input signals only Amplitude Accuracy 10 C to 35 C ambient 5 for signals between 600 and 1 Vp p 1 38 VM700T Video Measurement Set Service Manual Specification Table
266. lators Pulse Width Switch Curran 42V Modulator x PIN Sensing p lt 15VRET CURRENT SENSE 15CS 15CS 12CS SD OVERCURRENT a UNDERVOLTS JOVERVOLTS a PSFAILLED Alarm Logic UNDERVOLTS _OVERTEMP LED POWER FAIL LINE SENSE 1 T2 POWER OFF 4 144V Fan 412V Drive FAN Figure 3 13 Simplified block diagram of the power supply FANRET 12 V and 15 V Regulators The 12 V and the and 15 V regulators are similar in operation The 12 V regulator is operating with more head room than the and 15 V regulators and the circuitry is modified to adjust for that difference Each regulator is a combined operational amplifier and FET current pass element with a feedback loop to the operational amplifier from the output voltage 3 32 VM700T Video Measurement Set Service Manual Theory of Operation Alarm Sensing Alarm Sensing circuitry looks at the various supply voltages to check for undervoltage overvoltage overcurrent and power fail conditions The status of these conditions are the signals fed to the Alarm Logic circuitry Alarm Logic Each of the alarm sensing outputs is monitored by the Alarm Logic circuitry That circuitry also monitors the temperature sense signals Depending on the state of the sense signals the Alarm Logic circuitry can issue a shutdown signal SD to the Pulse Width Modulator PWM to stop the power supply from operating The
267. le 1 87 Frequency and Noise specifications Cont Measurement Specification Comments Resolution 0 1 dB Frequency Range 20 Hz to 20 kHz Accuracy 1 Hz for input gt 60 dBu Resolution 1 Hz for input gt 60 dBu Phase Difference Minimum input level for 40 dBu specified accuracy Phase measurement error 1 for inputs at 40 Hz to 20 kHz 2 for inputs at 40 Hz to 20 kHz Total harmonic distortion amp noise THD N Measurement bandwidth 33 Hz to 22 kHz Input level z 20 dBu Residual THD N 0 03 Maximum measurement 70 0 Accuracy 10 of reading 1 digit for harmonics Channel Separation Measurement Window 24 Hz Measurement is taken in the undriven 20 Hz to 350 Hz 96 Hz channel The measurement window follows the driven channel signal frequency gt 350 Hz Constant bandwidth Measurement Filter Plot Mode Minimum frequency change 2 Hz Minimum dwell time 1 sec for input frequencies 500 Hz 500 ms for input frequencies gt 500 Hz Table 1 88 Accuracy and Flatness specifications Accuracy includes Frequency range Level range flatness Flatness 20 40 Hz gt 20 dBu 0 3 0 2 dB 0 1 0 2 dB 20 dBu to 50 dBu 0 4 0 3 dB 0 1 0 2 dB 50 dBu to 60 dBu 0 6 0 5 dB 0 1 0 2 dB 60 dBu to 70 dBu x 1 0 dB 0 1 0 2 dB 40 Hz 20 kHz gt 20 dBu x 0 1 dB 20 dBu to 50 dBu x 0 1 dB 50 dBu to 60 dBu 0 0 1 dB 60 dBu to 70 dBu 0 1 dB 1 Level differences between channels is 0
268. le adapter collar Figure 6 7 Option 41 Triple Input Audio input connector Pin locations 2 2 eee ce cece etre cece hh hn nn 5 28 5 30 5 31 6 7 6 8 6 10 6 10 6 11 6 13 6 13 VM700T Video Measurement Set Service Manual Table of Contents Figure 6 8 Ferrite forms installed on the Option 41 interconnection cable Figure 6 9 Loosening the screws on the right card cage retainer Figure 6 10 Figure 6 11 Figure 6 12 Figure 6 13 Figure 6 14 Figure 6 15 Figure 6 16 Figure 6 17 Figure 6 18 Figure 6 19 Figure 6 20 Figure 6 21 Figure 6 22 Keypad board Figure 6 23 Figure 6 24 Figure 6 25 screws Figure 6 26 Figure 6 27 Figure 6 28 Figure 6 29 Figure 6 30 Figure 6 31 Figure 6 32 Figure 6 33 Figure 6 34 Figure 6 35 Figure 6 36 Figure 6 37 Figure 6 38 Figure 6 39 Figure 6 40 Figure 6 41 Figure 6 42 Figure 6 43 Location of right card cage circuit boards Acquisition Memory board A18 cables SDI board A22 cable connections Installing the SDI Rear Panel Interface A23 assembly Disconnecting the Analog Input board connectors Removing screws from the signal input connector plate Removing the Genlock board Removing the ADC board Removing the Filter Switch board Locating the bezel retaining screws Disconnecting the STBY ON circuit board Removing the retaining screws from
269. le channel signal path but the ADC board is the most likely problem area when all channels are affected VM700T Video Measurement Set Service Manual 5 7 Adjustment Procedure 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 5 8 Change the TV standard parameter from PAL to NTSC by pressing the XY Arrow hard key Change the filter selection from No Filter to NTSC Band Width Limiting Filter by pressing the Move Expand hard key until the filter displays NTSC BW Lim Return the leveled sine wave generator to 50 kHz do not change the output level setting Let the display stabilize Adjust the NTSC BP filter 50 kHz Level adjust on the Filter Switch board so that the change in amplitude Delta Amp is within 0 02 of the reference level stored in step 4 See Figure 5 1 on page 5 5 for the adjustment locations Reset the leveled sine wave generator for 3 6 MHz do not change the output level setting Let the display stabilize Adjust the NTSC BP Filter Flatness adjust on the Filter Switch board so the change in amplitude Delta Amp is within 0 02 of the reference level stored in step 4 Change the Filter parameter from NTSC BW Lim to Chroma BP by pressing the Move Expand hard key Don t change the settings on the leveled sine wave generator Let the display stabilize Adjust the Chroma Filter Level adjust so that the change in amplitude Delta Amp is within 0 02 o
270. le effects from the measurement see the gain phase analyzer operator s manual for the procedure to normalize the cables 7 Disconnect the SMB cable and the SMB to BNC adapter from the BNC cable going to the output of the gain phase analyzer and connect that cable to the VM700T channel A input terminate channel A with 75 9 termina tion VM700T Video Measurement Set Service Manual Adjustment Procedure 8 Connect the input of the gain phase analyzer to J550 on the Analog Input board through the SMB cable SMB to BNC adapter and BNC cable just normalized 9 Bypass the Filter Switch board by removing the cables from J922 and J923 on the Analog Input board and connecting the jumper removed from J924 between J922 pin 2 and J923 pin 2 10 Check that the frequency response for channel A is flat within 30 mdB peak to peak one major division on the example test equipment display to 8 MHz NOTE If the frequency response for channel A meets the specification do not make any adjustment to attempt to improve the response curve of channel A 11 If the channel A frequency response is outside the limits specified in step 11 adjust R186 C922 and R555 for a flat response on the analyzer out to 8 018 669 64 Hz see Figure 5 1 on page 5 5 for adjustment locations The following steps describe the procedure a Set R186 and R555 at midrange b Adjust C922 to get the 6 MHz to 10 MHz portion of the response curve centered
271. least 10 frequencies over the entire range Tested frequencies should include the specification limits 20 Hz 20 kHz and the 40 Hz breakpoint Example frequencies to test might also include the following 100 Hz 200 Hz 1 kHz 2 kHz 10 kHz 3 Check that the measured frequency is accurate to the limits shown in Table 4 3 for the applied test signal frequency and level Check that the phase difference between channels meets the phase difference specification VM700T Video Measurement Set Service Manual SS EE Ee Audio Option 41 Triple Input Verification Procedure This section describes the differences in operation between Option 40 and Option 41 and it gives the verification procedure for Option 41 Configuring Source Selection Audio The Option 41 software is similar to the Option 40 software except for the Source Selection Audio file The Source Selection Audio file lets you specify an Option 41 audio input 1 2 3 for a video source A B C and then select an appropriate audio source file if you want to use an audio source file other than the system default In the next steps you want to have source A to audio input 1 source B to 2 and source C to 3 To specify audio inputs and audio source files for video sources use the following procedure 1 gU EE o From Measure Mode press the Configure front panel button touch the Configure Files soft key followed by the Source Selection Audio soft key Rotate th
272. ly compensates for the distortions that occur when the SDI signal travels down a length of cable The equalizer amplifies the signal and reshapes the waveform to make the edges fairly distinct Clock Recovery This block is a phase locked loop that creates a regular clock from the irregular data transitions that are contained within the SDI stream Deserializer The deserializer takes the SDI data stream from the equalizer and the clock recovered from the clock recovery circuitry to convert the serialized data into 10 bit parallel data The alignment of the serial data is determined from the embedded TRS marks Since they are the only data patterns where all 10 bits are either zeros or ones they provide a clear indication of how the data words are aligned in the SDI data stream Line and Frame Synthesizer This block examines the 10 bit parallel data stream to identify the TRS marks that indicate line and frame transitions For line transitions the synthesizer sets the line bit according to the H bit in the TRS XYZ word For frame transitions the synthesizer sets the frame bit according to the V bit in the TRS XYZ word The V bit is deglitched by requiring eight consecutive XYZ words four lines with the V bit having the new value before actually setting the V bit itself Channel Selection MUX The channel selection MUX selects between the two SDI channels EDH Coprocessor The EDH coprocessor detects and decodes EDH errors The coprocesso
273. ment disconnect the power bus cable at its five connectors and then remove the cable g From the bottom of the instrument remove the connectors and terminal wires between the power supply and the Interconnect board assembly h Inside the left card cage remove the six screws holding the Interconnect board assembly to the card cage back panel see Figure 6 25 NOTE The Interconnect board assembly retaining screws are easier to remove if you first place the instrument on it s right side and then use a long shank screwdriver allowing more hand clearance to remove them i With the instrument placed upside down carefully push the power supply wiring aside and move the Interconnect board assembly up and out of the chassis 2 Replace the Interconnect board assembly by performing step 1 in reverse order VM700T Video Measurement Set Service Manual Maintenance Q9 Figure 6 25 Removing the Interconnect board assembly retaining screws Cooling Fan To remove and replace the cooling fan first remove the top and bottom cover panels the power supply and the harness retainers that attach the fan s wire harness to the bottom of the left card cage Next remove the cooling fan and its guard by removing the retaining screws and nuts Use the following steps to remove or replace the cooling fan 1 Perform the following steps to remove and replace t
274. mple Video amplitude calibrator Square wave 0 0 mV to Reference standard for Tektronix 067 0916 00 not 999 9 mV peak accuracy amplitude verification currently available for 0 0596 resolution 0 1 mV purchase Leveled sine wave generator 75 Q output impedance Measure sine wave check Hewlett Packard 3336C output flat within 0 025 dB filter flatness Sine wave generator with 20 396 to 6 MHz option 005 Television signal generator NTSC full field and burst NTSC test signal source Tektronix TSG 170A or capability accurate to 1 Hz equivalent Television signal generator PAL full field and burst capa PAL test signal source Tektronix TSG 271 or bility accurate to 1 Hz equivalent Coaxial cable BNC connectors 75 Q impedance high quality Signal interconnections Tektronix part number noise free 1 meter length 012 0074 00 Termination 75 Q precision BNC Signal termination Tektronix part number connectors 011 0102 01 1 The example amplitude calibrator requires a TEGAM TM500 or TM5000 series power module The flatness accuracy required of the leveled sine wave generator is only to the bandwidth needed to perform the measurement set verification and adjustments It is not specified to be that flat over the entire bandwidth of the generator 4 6 VM700T Video Measurement Set Service Manual Performance Verification System Verification Procedures NOTE If the results yielded by the verification procedures in this section are
275. n 48 the GPIB option This option provides a interface for remote control in a GPIB controlled system Operation of the GPIB option is described in the VM700T GPIB Interface Option 48 Programmer manual VM700T Video Measurement Set Service Manual Theory of Operation Module Functional Description This part describes the operation of each circuit board module in the VM700T Block diagrams accompanying the text show the functions of the modules Analog Input Board A1 Loop Through Inputs Mode Control Clamped Input Amplifiers Clamp and Bias Generator Channel Selection The analog input board performs input selection and applies bias clamping offset gain and dither to the input video before digital conversion This board also contains a calibration DAC digital to analog converter that is automati cally switched into the signal path to ensure accuracy A block diagram of the module is shown in Figure 3 1 The three video channels and the external sync signals have independent high impedance loop through inputs The clamped input amplifiers are high input impedance devices to minimize loading of the loop through signals The mode control block passes or decodes instructions from the acquisition con troller board These instructions control the clamped amplifiers sync selection channel selection calibration DAC cal relay operation and the DVM selection The clamped input amplifiers there are three one for each ch
276. n of the VM700T Video Measure ment Set using the major circuit blocks as modules This section has two main parts m Overview of the VM700T System describes the system operation of the modules circuit boards m Module Functional Description describes circuit operation of the modules from a functional circuit block perspective Block diagram illustrations accompany the appropriate text Overview of The VM700T System The video signal enters the VM700T analog input board A1 through one of three high impedance loop through connectors see the overall block diagram in the diagrams sections of this manual After it buffers and clamps the input signal and selects a channel the A1 board passes the signal to the 4 filter switch board where analog filtering signal conditioning occurs After filtering the filter switch board returns the video signal to the A1 board for analog processing offset gain and dither are dynamically applied The signal then passes to the analog to digital ADC converter board A3 where it is digitized The A2 genlock board uses an external sync or the sync from one of the three video input channels to create a sampling pulse synchronized genlocked to the incoming sync pulses A 10 bit analog to digital flash converter digitizes the video signal After digital conversion the differential ECL data is clocked to the acquisition controller board A18 The data acquisition controller board A18 converts the
277. nance Display and Control This section describes removing and replacing the VM700T components Components Removal and responsible for instrument display and user interface These components include Replacement the CRT assembly the touch panel and the keypad board assembly Removing and replacing these components requires first removing the instrument cover panels the CRT bezel and to remove the keypad board assembly the right side card cage retainer This section describes removing and replacing the VM700T components responsible for instrument display and user interface These components include the CRT assembly the touch panel and the keypad board assembly Removing and replacing these components requires first removing the instrument cover panels the CRT bezel and to remove the keypad board assembly the right side card cage retainer Required Tools Use the following tools to remove the display and control components m Flat blade screwdriver 3 16 inch blade Combination wrench or nut driver 3 16 inch W Pozidriv screwdriver 1X 2X CRT Bezel Use the following procedure to remove and replace the CRT bezel l Perform the following steps to remove CRT bezel a Remove the instrument cover panels refer to Cover Panel Removal and Replacement on page 6 8 b Remove the four screws holding the bezel to the front frame see Figure 6 19 There is one screw on each side and one each in the top and bottom of
278. nance Delay Chrominance to Luminance Gain Ratio Table 1 19 Chrominance Noise Measurement AM Noise PM Noise Table 1 20 Chrominance Nonlinearity Measurement Chrominance Amplitude Chrominance Phase Chrominance to Luminance Intermodulation Table 1 21 Color Bar Measurement Luminance Level Chrominance Level excluding gray and black Chrominance Phase Absolute mode accuracy Relative mode accuracy 10 ns 0 to 160 20 1 Range 20 dB to 80 dB 20 dB to 70 dB Absolute mode accuracy 1 dB 20 dB to 60 dB 1 dB 20 dB to 60 dB Absolute mode accuracy Relative mode accuracy 0 to 360 20 2 Absolute mode accuracy Relative mode accuracy 0 to 700 mV 1 0 of nominal 0 2 04 VM700T Video Measurement Set Service Manual 1 13 Specification Table 1 22 Differential Gain and Phase Measurement Differential Gain Minimum Maximum and Peak Differential Phase Minimum Maximum and Peak Absolute mode accuracy Relative mode accuracy Table 1 23 Frequency Response and Group Delay Measurement Frequency Response to 5 MHz to 6 MHz Group Delay to 5 MHz to 6 MHz Table 1 24 Horizontal Blanking Measurement Blanking Start Blanking End Blanking Width Table 1 25 Horizontal Timing Measurement Burst Level Horizontal Sync Rise and Fall Time Horizontal Sync Width Burst Width Sync to Burst Start Sync Level Absolute mode accuracy Relative mode acc
279. nces between the measured levels recorded for each frequency are within the flatness specification given in Table 4 3 Check Distortion and Distortion Measurement Accuracy This procedure verifies that residual THD N is 0 03 or less and then checks the THD N accuracy of the audio option by reading a known signal Specification Checked THD N accuracy is 10 of the reading 1 digit for harmonics at input levels of 20 dBu or greater in a 33 Hz to 22 kHz bandwidth Option 40 Distortion 1 Check residual THD N Measurement Accuracy a Apply a signal between 20 dBu and 30 dBu from sine wave generator to the VM700T Audio Option 40 See Figure 4 7 for a cabling diagram The generator should be set at 50 2 output resistance To Option 40 audio input connector b 5 5 Figure 4 7 Option 40 cable connections distortion measurement accuracy check b Run the Audio Analyzer measurement and verify that residual THD N is 0 03 or less An applied signal of 8 dBu to 10 dBu yields an optimal reading while a 20 dBu signal yields a worst case reading VM700T Video Measurement Set Service Manual 4 17 Audio Option 40 Verification Procedure Check THD N Measurement Accuracy a With 600 Q output resistance selected connect the outputs of two sine wave generators in parallel to the left channel input of the Audio Option See Figure 4 7 for a cabling diagram b Set sin
280. nd Flatness 4 15 Check Distortion and Distortion Measurement Accuracy 4 17 Specification Checked 0 00sec cece eee E eee 4 17 Option 40 Distortion Measurement Accuracy 4 17 Check Frequency and Phase Measurement Accuracy 4 18 Specifications Checked gt 4 18 Option 40 Frequency Accuracy and Channel Phase Difference 4 18 Audio Option 41 Triple Input Verification Procedure 4 19 Configuring Source Selection Audio 4 19 Check Level Measurement Accuracy and Flatness 4 20 Option 41 Level Accuracy and Flatness 4 20 Check Distortion and Distortion Measurement Accuracy 4 22 Option 41 Distortion Measurement Accuracy 4 22 Check Frequency and Phase Measurement Accuracy 4 23 Option 41 Frequency Accuracy and Channel Phase Difference 4 23 SDI Option 1S Performance Verification 4 25 Preliminary Setups es bee ea sers VN Me ER ER Re 4 26 SDI Analog Ref Input nn 4 27 Eye Diagram Application iti en 4 28 JittetzADpLIiCatiorn Lac otov sten be ette ees Diet v Y ess 4 30 Interchannel Timing Application
281. nd R658 to pull the data path high After setting up this way the data is acquired and checked to make sure all bits are high If so the test passes Otherwise a test failure is flagged and for each data bit that is not high a message is generated to the console VM700T Video Measurement Set Service Manual Troubleshooting Procedures Table 6 13 SDI Option 1S diagnostic test descriptions Cont Test name SDI Digital Paths Channel A Signal Lock Channel A Hsync Channel A Data Path Channel B Signal Lock Channel B Hsync Channel B Data Path SDI Eye Path SDI Jitter Path Description This group checks the operation of the digital data paths on the SDI board and consists of the following tests Three bits of information are generated by the front end to inform the rest of the system and the software about the status of the incoming signal The first of these indicates that there is a signal present and is generated at U61 19 for Channel A and U162 19 for Channel B The second bit originates at pin 4 of the same part but is read by the software at the other side of U160 for Ch A and U161 for Ch B If both of these bits is asserted high then the diagnostic will conclude that a valid signal is present on the corresponding channel When this is the case the Channel Signal Lock test will show pass and the next 2 tests will be performed Otherwise all three tests for that channel will be flagged as N A
282. nd address lines from the system bus are buffered on this board Many of the data and address lines are buffered on the board a second time before being used to drive multiple devices The majority of the control logic and high speed logic functions are incorporated into the controller ASIC application specific integrated circuit The controller now has new functionality for DVM and clamp gating The controller handles CPU interfacing DVM and clamp counter gating control bus routing control DVM counting and some of the buffers that handle data flow Address decoding is handled by the same decoder as for the Acquisition section of the board This block controls the dynamic gains offsets input selections and dither The dither counter is implemented in a PAL and octal D flip flop The output signals from this block are fed directly to the Analog boards in the top compartment of the instrument They perform the following actions W enables the controller board DVM block loads four control registers within the mode control and DVM selection blocks latches 12 as 8 4 bits of data into the calibration DAC located on the analog input board loads 8 bits of data into each register of the bias and clamp level octal DAC located on the analog input board There are stored patterns selected by the four bits from the control register are stored The selected pattern provides gating for input signal clamping and the DVM The g
283. nd the left right up down button In Auto mode rotating the control knob scrolls through the list of measurements When a user configurable parameter is selected for changing you can rotate the control knob to make the change For informa tion on the specific functions of the control knob in each mode refer to the relevant sections of the user documentation m Display and Graticule Intensity Control To change the intensity of either the display or the graticule hold down the appropriate button Display or Graticule and rotate the control knob VM700T Video Measurement Set Service Manual Operating Information m Select Line Button The Select Line button changes the function of the control knob from the default Move Expand action to line selection The LED in the Select Line button is on when Select Line is active To scroll through the field line by line press the Select Line button and rotate the control knob Depending on the operational mode a menu of soft keys may also appear when the Select Line button is pressed Refer to the relevant sections of the user documentation for a description of the Select Line soft keys and the specific control knob functions In the diagnostic menus use the Select Line button to activate a selected choice For additional information on diagnostic operation refer to Diagnostics beginning on page 6 55 Equipment Signal Sources Most measurements can only be made using either off air liv
284. nd the power supply can be severely damaged VM700T Video Measurement Set Service Manual 6 39 Maintenance 6 40 Interconnect Board Assembly A11 The Interconnect board assembly A11 consists of three circuit boards assembled with connectors screws and spacers This assembly is replaced as a unit VM700T circuit boards in the two card cages plug into the Interconnect board assembly Removing and replacing this assembly requires removing the boards from the card cages removing wires and attaching screws and lifting the main interconnect assembly from the instrument The following procedure describes removing and replacing the main interconnect assembly 1 Perform the following steps to remove the Interconnect board assembly a Remove the instrument cover panels refer to Cover Panel Removal and Replacement on page 6 8 b Remove the CPU board from the right side card cage refer to CPU Board A5 Removal and Replacement on page 6 15 c Remove the Acquisition Memory board refer to Acquisition Memory Board A18 Removal and Replacement on page 6 18 d Remove the I O board refer to Board A20 Removal and Replace ment on page 6 9 e Remove any installed option boards refer to Option 40 and Option 41 Audio Boards A12 A13 and A17 Removal and Replacement on page 6 11 and Option 48 GPIB Interface Board A19 Removal and Replacement on page 6 14 for more information f From the top of the instru
285. ndard length cable on the SDI Ch A input with 100 m of cable p Touch the Proceed soft key q Check that the Cable New Data is within the limits shown in Table 5 7 r Ifthe data is within the limits touch the Accept Data soft key s Touch the Update soft key and then touch the Really Update soft key t Replace the cable clone or the 100 m of cable with the standard length cable Leave the SDI Ch A input terminated Table 5 7 Cable meter adjustment value limits 10 MHz demod 2 100 to 2 600 2 000 to 2 500 77 MHz demod 2 000 to 2 500 1 800 to 2200 VM700T Video Measurement Set Service Manual 5 27 Test Equipment Depot 800 517 8431 99 Washington Street Melrose MA 02176 FAX 781 665 0780 TestEquipmentDepot com Adjustment Procedure 4 Perform the following steps to adjust the Eye Diagram horizontal position and delay a Slide the VM700T right side cover back to access the CPU board dip switch b Setswitch 4 of the dip switch to the open position and then close the side cover See Figure 5 12 c Setthe digital television signal generator to output a 525 line 143 Mb NTC7 combination signal E ad Acquisition board d SDI board CPU board Set switch 4 to open SDI board Figure 5 12 Location of CPU board dip switch and SDI board test point and adjustment resistor 5 28 VM700T Video Measurement Set Service Manual Adjustment Procedure
286. nel data is held in the audio data register That register is only big enough to hold one sample so it will contain either left channel data or right channel data 1 for left O for right A second data buffer is a read only buffer that holds the board version number Software reads these bits to determine the hardware version installed in the VM700T Other bits held in the data buffers indicate when a calibration is taking place and show which audio option is installed Option 40 or Option 41 Reset Register The reset register hold the reset bit as the last bit in the 32 bit interrupt register When the audio processor resets it sets the RESET line low to reset the DSP This line stays low until the audio processor forces it high to start the DSP DSP Processor and I O Interface The DSP is the heart of the Audio Measurement System The DSP has a 16 bit address bus and a 24 bit data bus Devices on the DSP bus include address decoders and buffers used to provides the extra drive needed to drive the memory load 18 memories Oscillator buffered oscillator running at 27 5 MHz provides the drive needed for the external clock input to the DSP Communication Ports communication ports handle parallel data flow between the DSP and the CPU the Host Port and serial data flow to the D A converters and control registers on the analog board One of the communications ports allows commu nications between the DSP and the CPU without havi
287. ng There is a diagnostic menu in the Low Level Diagnostic Interface select P in Figure 6 48 that can be used to override the boot switch setting for starting up the instrument from that menu That menu is the Instrument Run Modes Menu shown in Figure 6 49 Under normal operation the boot switch settings will remain in the factory default positions for shipment and the Instrument Runs Modes menu is not needed to override the boot switch VM700T Video Measurement Set Service Manual 6 71 Troubleshooting Procedures Low Level Diagnostic Interface knob moves cursor Select Line inputs selection INSTRUMENT RUN MODES MENU The instrument will be reset to run in the mode selected below overriding current boot switch settings Key Selection N NORMAL POWERUP Start Instrument in Powerup Mode Current Powerup Mode is QUICK START abort this menu and go to the DIAGNOSTICS CONFIGURATION MENU to change it P uus POWERUP DIAGS Do Diagnostics start Instrument Q were QUICK START au urn EOS Skip Diagnostics start Instrument L LOW LEVEL DIAGS LOOP Loop on Low Level Diagnostics D HIGH LEVEL DEBUG Start Instrument in HL Debug Mode A 5 Do EXTRA Diagnostics start Instrument Reprint Abort Menu Input your selection Figure 6 49 Instrument run modes menu From this menu you can override the normal
288. ng a board swap to effect repairs to the VM700T The normal use of the diagnostic tests is for factory testing prior to shipment to the customer and repair testing of the boards returned in the board exchange program VM700T Video Measurement Set Service Manual Troubleshooting Procedures Selecting an Overall Run Mode After you select one of the diagnostics to execute you get a further choice of how you want to run it The choices are shown in the Main Bd CPU Diagnostic menu Figure 6 35 as P A or C power up auto reset or custom mode respectively The menu choices for each of the diagnos tics Main Bd CPU Main Bd Display Main Bd Fr Pnl Infc and I O Board are all the same at this point The diagnostic selected determines which is to be interactively run Power Up mode runs the power up diagnostics as at normal power up with an abbreviated go no go test of the circuitry Auto Reset Mode runs all the power up diagnostic tests available for the given diagnostic These Auto Reset tests provide more extensive tests that exercise the circuitry for several seconds at each test The Custom choice permits you to select a single diagnostic test or build a selected set of diagnostic tests to run This mode allows access to any or all of the available low level diagnostic tests Low Level Diagnostic Interface Main Bd CPU Diagnostic Select an OVERALL RUN MODE from the list below Key Selection POWER UP Mod
289. ng pin 2 high then low waiting 33 ms for the device to lock to any external signal that may be present and then reading the status from the chip If the status says that there is no signal bit 2 of register SMPTE1 is 0 then the test is flagged as N A because this condition means that the chip thinks there is no valid signal connected If there is a signal the diagnostic merely reads the time code and prints it to the console after flagging the test as PASS since we have no means of comparing the timecode against a known reference to decide if it is correct we merely show it to the user and let them judge the correctness Audio Receiver The audio receiver chip is a crystal CS8412 and its functions are all hard wired on the board and thus not amenable to manipulation by the diagnostic program The diagnostic proceeds as follows Data Validity Flag There is a 3 bit field in the device which is used to report the status of the data This value is read and displayed and can have the following meanings for details please refer to the CS8412 data sheet OK 0 Data is valid VALFLG 1 Validity Bit High in data stream CONFLG 2 Confidence Flag SLIPPD 3 Slipped Sample CRCERR 4 CRC Error PARERR b Parity Error CODERR 6 Bi Phase Coding Error NOLOCK 7 No Lock Valid Data Mvmt If the data validity flag is NOLOCK then it means there is no signal and the second test is bypassed i e flagged N A Otherwise data acquisiti
290. ng the CRT To avoid electric shock or injury use extreme caution when handling the CRT Only qualified personnel familiar with CRT servicing procedures and precautions should remove or install the CRT CRIs retain hazardous voltages for long periods of time after power is turned off Before attempting any servicing discharge the CRT by shorting the anode to chassis ground When discharging the CRT connect the discharge path to ground and then the anode Rough handling may cause the CRT to implode Do not nick or scratch the glass or subject it to undue pressure when removing or installing it When handling the CRT wear safety goggles and heavy gloves for protection Use Care When Servicing With Power On Dangerous voltages or currents may exist in this product Disconnect power remove battery if applicable and disconnect test leads before removing protective panels soldering or replacing components To avoid electric shock do not touch exposed connections X Radiation To avoid x radiation exposure do not modify or otherwise alter the high voltage circuitry or the CRT enclosure X ray emissions generated within this product have been sufficiently shielded VM700T Video Measurement Set Service Manual xvii Preface This is a service manual for the VM700T Video Measurement Set It is a module level repair manual for use by a qualified service person in the isolation of faulty modules and repair by module exchange Contents of the
291. ng to do a bus request bus grant operation Another port is divided into two serial ports one for serial communications and the other is the synchronous serial interface VM700T Video Measurement Set Service Manual 3 35 Theory of Operation Audio Data Register CPU Access Disable Static RAM 3 36 P Memory X Data and Y Data Memory Program Loading Control Lines This register accepts serial data from the ADC on the analog board and converts it to parallel data for the DSP or the CPU A serial to parallel converter converts the serial data from either the ADC or the DSP generated for diagnostics to a 24 bit parallel data word used by the DSP If the DSP is set to generate interrupts when audio data arrives it must service the interrupts in a service routine At the same time the CPU can be trying to read or write data to the same address space being used by the DSP The DSP always gives up its bus to the CPU but this can cause a problem To avoid this bus sharing problem there is circuit that prevents CPU access to the bus during the data interrupt service routine The P program X data and Y data static RAM is composed of 18 25 ns devices Each RAM is 4 bits wide so six memory chips are used to make up the 24 bit word Each pair of chips accessed by the same write enable signal corresponds to one 8 bit byte Each byte has separate write enables because the CPU accesses only a byte at a time The static RAM is
292. nt panel board Figure 3 10 decodes input from the control knob and touch screen and relays push button and LED information to and from the A10A2 keypad board The front panel board connector to the display memory board contains most of the lines of the 68008 bus including lines for relaying push button and LED information to and from the keypad board Additional lines for power and the signals INTEGRATE and CLK200 are provided To From ADDRESS STATUS CONFIGURATION K DIGITAL CPU Board DECODER PORT REGISTER KNOB Tof rom Keyboard e AUTONULL OVERFLOW DETECTOR INVERTER SYNCHRONOUS A D DEMODULATOR INTEGRATOR CONVERTOR e CLK200 To From Touch MULTIPLEXER Panel Below B050100 To From Touch Controller Panel B050100 and above Figure 3 10 Front panel board block diagram VM700T Video Measurement Set Service Manual 3 27 Theory of Operation Keypad Board A10A2 The VM700T front panel push buttons LED and the control knob are connected to the keypad board The keypad board is connected to the front panel board through a flex cable that carries power the 68008 data bus enable signals from the front panel board s address decoder and two bits of data from the control knob Figure 3 11 shows the block diagram of the keypad board Control Knob control knob is a mechanical switch with conductive plastic contacts One terminal of the switch
293. ntenance f Plugin the three coaxial cables at J7 J8 and J10 See Figure 6 12 on page 6 21 for the proper cable connections Plug in the multicolored ribbon cable at J5 h Install the card cage retainer refer to step 4 on page 6 17 i Install the cover panel refer to Cover Panel Removal and Replacement on page 6 8 Analog Input Board Removing and replacing the Analog Input board A1 consists of removing the Removaland top cover removing four wires and two ribbon cables and removing the board s Replacement retainer screws With the screws removed the board may be lifted from the VM700T chassis and set aside Replacing the board is the reverse of this procedure You may use the following procedures to remove and replace the analog input board Required Tools Use the following tools to remove the Analog Input circuit board W Pozidriv screwdriver 1X 2X Procedure Use the following procedure to remove and replace the Analog Input board l Perform the following steps to remove the Analog Input board a Remove the top cover panel refer to Cover Panel Removal and Replacement on page 6 8 b Disconnect the wire at 7132 and the shielded cable at J6 and move them aside see Figure 6 14 for cable locations c Disconnect the ribbon cable at J965 d Disconnect the power bus cable at its five connectors and then remove the cable e Remove the wire connecting A4 J915 to A1 J922 at the J922 end only f Remove
294. ntroller trigger RAM can be used to recognize when certain bits in the ADC data stream are set Causes signal interrupts that are counted by the Controller s 5190 Sigt Sig2 counters Long Acquisitions Runs long acquisitions to verify interaction of Controller and Acquisition state machines 15 Sample Dropping Uses Controller state machine to toggle offset level a dynamic setting on the Analog Input board while a long acquisition runs Analyzes the acquired data to detect missing samples ADC A3 Mode Checks Output latches in all zeros all ones normal and overflow bit modes and checks the ADC output by running an acquisition and scanning Successful completion of acquired data The overflow bit test generates a drive level to these tests requires that overrange the board then acquires data and checks to verify that the Genlock A2 and board s overrange bit was set Acquisition Memory A18 boards be oper ating correctly Tests involving the Bit Patterns Generates a calibration DAC drive level that produces an ADC level Calibration DAC require corresponding to the bit pattern shown in the individual test The that the Analog Input diagnostic runs a long acquisition and searches the acquired data for A1 board be operating the individual test s bit pattern correctly Analog Input A1 Calibrates the DVM to the standard gating patterns for both TV standards and the gating pattern that enables the DVM for all video lines u
295. o 40 20 296 B2 CCIR Rec 567 096 nominal 0 to 40 of bar CCIR Rec 569 0 to 35 Field Square Wave 50 0 2 G1 or G2 CCIR Rec 569 0 nominal 0 to 50 0 nominal VM700T Video Measurement Set Service Manual Specification Table 1 44 Low Frequency Error Measurement Standard Low Frequency Error reported as 0 to 2596 CCIR Rec 569 CCIR LF Error 50 550 Hz LF Error 096 nominal 10 1000 Hz LF Error Table 1 45 Noise measurements Measurement Accuracy Standard Unweighted SNR 567 26 dB to 60 dB 1 0 dB Measured on one quiet line per CCIR Rec 567 61 dB to 70 dB 2 0 dB Luminance Weighted SNR 567 26 dB to 60 dB 1 0 dB Measured on one quiet line per CCIR Rec 567 61 dB to 70 dB 2 0 dB Chrominance Weighted SNR 26 dB to 60 dB 1 0 dB Measured on one quiet line per CCIR Rep 637 2 61 dB to 70 dB 2 0 dB Periodic SNR 26 dB to 60 dB 1 0 dB Measured on one quiet line per CCIR Rep 637 2 61 dB to 70 dB 2 0 dB Unweighted SNR 569 26 dB to 60 dB 1 0 dB Measured on one quiet line per CCIR Rec 569 61 dB to 70 dB 2 0 dB Luminance Weighted SNR 569 26 dB to 60 dB 1 0 dB Measured on one quiet line per CCIR Rec 569 61 dB to 70 dB 2 0 dB Table 1 46 Incidental Carrier Phase Modulation Measurement Range Accuracy ICPM requires Zero Carrier Pulse and the quadrature output of the 0 to 30 1 0 demodulator on Channel C 1 20 VM700T Video Measurement Set Service Manual Specification NT
296. o The Analog Video soft key changes the measurement set to Analog Mode and displays the analog measurement applications User Programmable Functions Hardcopy Remote Operation 2 10 You can define a sequence of operations as a new function For example you can create a function that makes the measurements on a transmitter demodulator video output You can label this function DEMOD build it to make all the measurements and provide a printout of the results You can also call another function from within a function to produce a set of measurements You can use a printer that supports PostScript or 24 pin Epson graphics through the standard RS 232C interface to hard copy the on screen information You can used most types of ASCII printers to print the results of Automatic measure ments using the same interface You can also send hard copy output to a parallel printer through the Centronics compatible parallel printer port The measurement set can be operated from a remote terminal through either of the RS 232C ports to monitor unattended transmission systems or to put systems under computer control The VGA output connector on the rear panel provides a copy of the measurement set display for remote viewing on a standard VGA monitor GPIB port is added for remote control or hard copy output to a GPIB printer with Option 48 installed VM700T Video Measurement Set Service Manual Operating Information Front Panel Controls The
297. of internal diagnostics 6 Check that all tests pass as they run If a test fails refer to Diagnostics on page 6 55 for further actions you can take to determine which board or boards may be at fault If you need further assistance contact your nearest Tektronix representative or call Tektronix Customer Service Option 1S Adjustment Procedure Required Equipment Table 5 4 lists the test equipment required to perform the adjustments to the VM700T Option 1S hardware Table 5 4 Test equipment required for Option 1S adjustment Equipment Digital television signal generator Clock generator Oscilloscope Clock source Cable clone or 100 meters of cable Coaxial cable 3 BNC female to BNC female connector 2 Termination Alignment tool Minimum specification Example 143 Mb 525 line NTC7 combination Adjusting the Cable Meter Tektronix TG 2000 Signal Genera signal 270 Mb 525 line 100 color and the SDI Eye Diagram tion Platform with a DVG1 module bars signal 360 Mb 525 line any horizontal position television signal Wave shape square wave duty Adjusting the Jitter applica Tektronix TG 2000 Signal Genera factor 40 to 60 tion tion Platform with a BG1 module Frequency 67 5 MHz 5 ppm must use the Clock Out connector Amplitude 350 to 850 mV p p 20 to 80 rise fall time lt 1 ns Jitter lt 150 ps p p measured from 10 Hz to 10 MHz 100 MHz bandwidth Adjusting the 18 MHz refer Tektronix 2
298. on Table 1 55 SMPTE color bar nominal values Cont Color Green Magenta Red Blue Phase eges Table 1 56 Differential Gain and Phase Measurement Differential Gain Differential Phase Absolute mode accuracy Relative mode accuracy 0 to 360 20 03 Table 1 57 Frequency Response and Group Delay Measurement Frequency Response Group Delay Table 1 58 Horizontal Blanking Measurement Blanking Start Blanking End Blanking Width Table 1 59 Horizontal Timing Measurement Burst Level Horizontal Sync Rise and Fall Time Horizontal Sync Width Burst Width Sync to Burst Start RS 170A Sync to Burst End FCC Front Porch Absolute mode accuracy Relative mode accuracy 40 dB 1 0 dB 20 3 dB 515 Absolute mode accuracy 0 1 usto 4 2 us 50 ns 6 8 us to 12 2 us 50 ns 6 9 us to 16 4 us 50 ns Range Absolute mode accuracy 10 to 80 IRE 20 596 80 ns to 1 us 10 ns 3 us to 7 us 10 ns 0 1 cycle FCC 0 5 cycle RS 170A 4 us to 10 us 150 ns 6 cycles to 13 cycles 4 us to 10 us 25 ns 10 ns FCC 10 ns RS 1704 0 1 usto 3 5 us VM700T Video Measurement Set Service Manual 1 23 Specification Table 1 59 Horizontal Timing cont Measurement Absolute mode accuracy Sync to Setup 10 ns Breezeway FCC 25 ns Sync Level 0 5 Table 1 60 Incidental Carrier Phase Modulation Absolute mode accuracy 1 0 Measurement ICPM requires zero Carrier
299. on Modes Video input or external Sound in syncs and PCM capable without jumper options Amplitudes Internal Minimum 14 dB with respect to 286 mV nominal sync amplitude Maximum 12 dB with respect to 286 mV nominal sync amplitude External Minimum 8 dB with respect to 286 mV nominal sync Composite sync amplitude Maximum 8 V peak to peak Composite sync VM700T Video Measurement Set Service Manual 1 3 Specification Physical Characteristics Table 1 4 Physical characteristics Characteristic Description Dimensions W x H x D 19 0 in x 8 75 in x 21 9 in 483 mm x 222 mm x 556 mm Weight 45 Ib 20 kg Shipping Weight Approximately 71 Ib 33 kg Power Requirements Table 1 5 Power requirements Characteristic Description Mains Voltage 90 VAC to 132 VAC 115 VAC nominal 180 to 250 VAC 230 VAC nominal Mains Frequency 50 or 60 Hz Power Consumption 250 Watts 400 VA maximum Fuse Rating Low Input Range 6A slow blow High Input Range 3A slow blow Cooling Method Forced air circulation Environmental Table 1 6 Environmental specification Characteristic Performance requirement Temperature Operating 0 C to 50 C Nonoperating 55 C to 75 C Altitude Nonoperating To 50 000 feet 15240 meters Operating To 15 000 feet 4572 meters Sine Vibration 1 4 VM700T Video Measurement Set Service Manual Specification Table 1 6 Environmental specification Cont Characteristic Operating Shoc
300. on is performed and the diagnostic checks all 10 bits to verify that they are all toggling If they are not then the diagnostic generates a message to the console for each bit that is not toggling Spurious Data Mvmt The third test is run only if there is no valid data since in that case the chip is supposed to output a data stream of all zeroes Hence the third test checks for bits that are not zero since this indicates a spurious data movement condition Each such bit is annunciated via a message on the console VM700T Video Measurement Set Service Manual 6 109 Troubleshooting Procedures Table 6 13 SDI Option 1S diagnostic test descriptions Cont Test name 12C and EDH Chips PCF8584 Rd Wrt EDH Chip All Low High Bits 6 110 Force Low Data Force High Data Description The 12C chip is a Philips PCF8584 device that provides a 2 wire interface by which ICs can communicate with each other The CPU in the VM700T uses this device to communicate with the Gennum GS9001 Error Detection and Handling Coprocessor EDH chip The 12 interface is tested first and if it works then it is used to do a limited amount of communication with the EDH chip There is only one register in the 12C chip U59 which can be both read and written all others are read only or write only This register is tested by writing and reading back a series of test patterns If there is a mismatch a message is generated to the console to indica
301. onnecting A4 J915 to A1 J922 f Replace the wire connecting A4 J418 to A1 J923 Install the power bus cable on its five connectors h Install the cover panel refer to Cover Panel Removal and Replacement on page 6 8 Genlock Board Removal Removing the Genlock board A2 consists of removing the VM700T top and and Replacement right side cover panels removing the ADC board disconnecting a flat cable and VM700T Video Measurement Set Service Manual 6 25 Maintenance a wire and removing seven screws With the screws removed the board may be lifted from the VM700T chassis and set aside See Figure 6 16 for the location of the genlock board Use the following procedures to remove and replace the Genlock board Required Tools Use the following tools to remove the Genlock circuit board m Pozidriv screwdriver 1X 2X Procedure Use the following procedure to remove and replace the Genlock board 1 Perform the following steps to remove the Genlock board a Remove the top and right side cover panels refer to Cover Panel Removal and Replacement on page 6 8 Remove the card cage retainer refer to step 1 on page 6 16 Disconnect the flat 10 conductor cable between J111 on the ADC board and J6 on the Genlock board see Figure 6 16 Disconnect the power bus cable at its five connectors and then remove the cable Disconnect the ribbon cable between the Genlock board and the Acquisition Memory board from the Genlock
302. onverter The clamping circuit holds the input signal swing to approximately 4 4 volts peak positive or negative This circuit is actually a 150 kHz low pass filter This filter is a 3 pole Bessel type circuit with exceptional phase performance The A D converter is a delta sigma type oversampling converter running at 64 times the required output frequency In this circuit the 150 kHz low pass filter circuit at the input of the A D converter provides anti alias protection The analog data applied to the inputs of the A D converter is processed by the converter and output as serial digital data The left right channel data is controlled by the L R signal and alternated in the data stream AJD Converter Self Cal The CAL signal applied to the A D converter causes a self calibration on the falling edge of the signal During the self cal time the A D converter checks the DC offset on its analog inputs The offset is stored in a register and subtracted from the data sent from the converter This operation zeros the internal offset of the converter and any offset generated by the operational amplifiers or any other DC offset in front of the inputs Up to 250 mV offsets can be removed but the usual offsets are not more than 10 mV During the Self Cal offset calibration a signal is sent to the DSP to keep it from interrupting the A D converter during calibration That signal is removed when calibration is complete The control signals sen
303. oo Per REED EDEN Puer Ms POE a s 3 10 SLAMS Me ET 3 10 ii VM700T Video Measurement Set Service Manual Table of Contents The Analog to Digital ADC Board 42 5 V and 2 5 V Regulators oem her eR ens Signal Conditioning Amplifier 8 A D Converter Buffer Output Latch Line and Frame Pulse Pipeline oeseri raa eee eee Overrange Detector Sample Clock Filter Switch Board A4 Filter Select and 1 Slot O cere Slots 1 5 Output Amplifier CPU Board A5 System Bus EPROM NVRAM NVRAM SIMM Flash EPROM DRAM Real Time Clock Display ASIC and ves ri eia e EE EEA EIERE Front Panel Processor CPU I O Board 20 Serial Ports Parallel Port Interface 32 Bit Counter Connector Data Acquisition Controller Board A18 Video Data and Clock Inputs FIFO Demultiplexor Acquisition Control Acquisition Clock Data Bus Interface Data Acquisition Memory Static RAM Min Max ASIC Controller Section Bus Buffers Controller ASIC Address Decoding Output Latches and Analog Input Board Int
304. or possible excessive loading on a power supply by the VM700T Troubleshoot the VM700T for excessive loading problems Circuit boards may be unplugged one at a time to check for board related loading If the over current fault goes away after you remove a circuit board or disconnect a cable assembly from the instrument that circuit board may be the faulty module Replace with a known good module to check Return a faulty module for replacement or repair Minimum load to maintain operation of the power supply is 30 W total including at least a 10 W 2A load on the 5 1 V supply VM700T Video Measurement Set Service Manual Troubleshooting Procedures Power Supply Voltage and Ripple Check To check the power supply for voltage and ripple tolerances the bottom cover of the VM700T must be removed Turn off the VM700T and remove the bottom cover Use Figure 6 62 to locate the power supply voltage test points this information is also on the bottom cover of the power supply Refer to Table 6 10 for the tolerance and ripple values 15V GND GND 12V Fan GND x 45V Ground 52 V 45V Figure 6 62 Power supply test points Table 6 10 Power supply voltages Voltage Tolerance standard P A R D max mV Circuitry supplied load ripple 15 Vdc 1 18A TTL Logic SCO FanDrive VH MA
305. or steps Gain steps Notch filters Left flatness Right flatness 6 98 Description Self calibrates the ADC and calibrates the output of the DAC against the chopper Gain is the ratio of DAC to chopper output Offset is the difference between the signal midpoint of the DAC and that of the chopper Checks for completion of the ADC internal self calibration and calibrates the ADC against the chopper Gain is the ratio of acquired signal amplitude to chopper reference ampli tude Offset is the difference between acquired signal midpoint and ADC midrange value Tests for walking 1 and walking 0 bit patterns in DAC sample data DAC and chopper signals are routed via all possible paths to the ADC with gain and attenuation set to 0 to verify continuity and separation of the two input channels Signals from the DAC are routed through the available attenuator steps acquired by the ADC and analyzed Attenuation is the ratio of atten off to atten on voltage Signals from the DAC are routed through the available gain stages acquired by the ADC and analyzed Gain is the ratio of gain on to gain off voltage DAC signals are routed through the notch filters and gain is measured as the ratio of notch on to notch off voltage Tests left channel flatness with sine waves generated by the DAC gain and attenuation are 0 dB and the notch filter is off Tests right channel flatness with sine waves generated by the DAC gain and attenuation
306. orate mode If there is a difference the test fails Repeat of the checks run for channel A This group checks the calibration DAC the voltmeter and associated circuits on the board The tests are as follows The voltmeter U28 has 16 possible inputs feeding it through U26 after selection through the analog muxes U25 and U121 Each of these inputs is selected in turn converted and displayed For the 4 inputs that are connected to known values i e U25 4 and U121 6 to 2 5000 VDC and U25 11 and U121 9 to ground the values are read and compared against high and low limits In these 4 cases the tests will fail if the values are out of limit The other 12 inputs are simply read and displayed with the tests always flagged as PASS One of the outputs of the calibration DAC U135 21 is connected to one of the inputs of the voltmeter via U121 10 This fact is exploited to perform a wraparound test using three different voltages 0 0 1 25 and 2 5 VDC VM700T Video Measurement Set Service Manual Troubleshooting Procedures Table 6 13 SDI Option 1S diagnostic test descriptions Cont Test name Description PLL Centering This test verifies the tuning range of the VCO phase lock loop at 143 Mb 270 Mb and 360 Mb LTC Chip The LTC chip U60 receives longitudinal time code from an external source The chip is a ICS 2008A Its functions are entirely hard wired and the diagnostic has little to do except reset the device by toggli
307. ounted VM700T VM700T Startup Touch screen calibration display Touch screen calibration panel Panel calibration values Diagnostic configuration menu Set diagnostics power up mode menu The VM700T Video Measurement Set front panel Measurement set keypad VM700T Video Measurement Set rear panel Video signal input connectors Cables and connectors supplied with Audio Option 40 Option 40 connectors and pin assignments Option 41 input connector pin locations GPIB board rear VM700T rear panel with Option 1S installed Option 1S rear Figure 3 1 Analog input board A1 block diagram Figure 3 2 Figure 3 3 ADC board block diagram Figure 3 4 Figure 3 5 Figure 3 6 Figure 3 7 Acquisition circuitry block diagram Figure 3 8 Figure 3 9 Figure 3 10 Figure 3 11 Figure 3 12 Figure 3 13 Figure 3 14 Figure 3 15 Figure 3 16 Figure 3 17 Figure 3 18 Figure 3 19 Figure 3 20 Genlock board A2 block diagram Filter switch board A4 block diagram CPU board block diagram CPU I O board block diagram Controller section block diagram Dither generator 64 step dither waveform Front panel board block diagram Keypad board A10A2 block diagram Picture Monitor simplified block
308. ove 1 6 to 2 4 us 2 Perform the following steps to check the digital to digital mode of the SDI Interchannel Timing application a Remove the signal cable and terminator from the Option 1S Analog Ref input and then remove the terminator from the SDI Ch A input loopthrough b Connect a one meter cable from the SDI Ch A input loopthrough to the SDI Ch B input c Touch the Relative Digital soft key d Check for an interchannel timing measurement reading of 37 ns e Remove all cable and terminators from the VM700T VM700T Video Measurement Set Service Manual SDI Option 1S Verification Procedure SDI Output Perform the following procedure to check the SDI Output signal 1 2 Connect 270 Mb 525 line 100 color bars signal to the SDI Ch B input Connect a one meter cable from the SDI Output to the SDI Ch A input Terminate the SDI Ch A input using a 75 2 high frequency terminator Press the VM700T front panel Configure button Touch the Configure Files soft key and then touch the Source Selection Digital soft key Highlight the SDI Output line using the front panel knob and then touch the highlighted line to cause a box to appear around the current selection Turn the knob to select Channel B and then touch the Accept Input soft key Touch the Update amp Exit soft key to exit the configuration file Press the front panel Measure button and then touch the SDI EyeDiagram soft key Pres
309. p view the A18 board A2 J6 J111 A3 Figure 6 17 Removing the ADC board f Install the power bus cable at its five connectors Install the card cage retainer refer to step 4 on page 6 17 h Install the top and right side cover panels refer to Cover Panel Removal and Replacement on page 6 8 VM700T Video Measurement Set Service Manual 6 29 Maintenance 6 30 Filter Switch Board Removal and Replacement Removing and replacing the Filter Switch board A4 consists of removing the instrument top and right side covers removing a flat cable assembly discon necting two wires and a cable and removing the screws holding the board in position With the screws removed the board may be lifted from the VM700T chassis and set aside Replacing this board is the reverse of the removal procedure You may use the following procedures to remove and replace the filter switch board Required Tools Use the following tools to remove the Filter Switch circuit board W Pozidriv screwdriver 1X 2X Procedure Use the following procedure to remove and replace the Filter Switch board l Perform the following steps to remove the Filter Switch board a Remove the top and right side cover panels refer to Cover Panel Removal and Replacement on page 6 8 b Remove the card cage retainer refer to step 1 on page 6 16 c Disconnect the power bus cable at its five connectors and then remove the cable see Fig
310. per response curve limits Adjust ments of C436 and C335 are interactive and may need to be repeated several times to obtain the best response curve 24 Reconnect the SMB cable between Analog Input board and the ADC board J550 to J765 and connect the gain phase input cable to J2 on the board 25 Set the controls on the gain phase analyzer as needed For the example gain phase analyzer the controls are set as shown in the following gain phase analyzer setups in Table 5 3 Table 5 3 Gain phase analyzer setup for ADC Control Setting A max 8 4 dB Aldiv 30 mdB Function GainPhase Sweep Log Osc Level 300 mVolts Start Freq 100 kHz Stop Freq 20 MHz Marker 5 8 MHz Output Dual Input Ref 75 Q 0 dB Input Test 1 Meg 20 dB 26 Check that the frequency response is flat with 1 division 30 mdB up to 5 8 MHz on the gain phase analyzer VM700T Video Measurement Set Service Manual 5 19 Adjustment Procedure 27 28 29 30 31 32 33 34 35 36 If the frequency response is not flat within 30 mdB adjust C57 the MID FREO adjustment and R22 the HIGH FREO adjustment as needed to obtain the correct response See Figure 5 1 on page 5 5 for the adjustment locations Disconnect both gain phase test cables from the VM700T Connect the sine wave generator and a terminator to the inputs of channel A Set the sine wave generator for a frequency of 43 297 kHz at a level of 3 81 dBm Select Measur
311. powerup settings and start up the VM700T in any of the indicated start up modes for one time The Autoreset choice runs all the diagnostics prior to initializing and it is a good choice when running the Verification procedure 6 72 VM700T Video Measurement Set Service Manual Troubleshooting Procedures VM700T Boot Switch and Boot switch is located at rear outer corner of the CPU board when viewed Diagnostic LED facing the right side of instrument and looking down at the CPU board In Figure 6 50 the Boot switch is shown in the Normal setting That is with all switches set to the CLOSED position pushed in at top This is the normal setting for Quick Start operation of the VM700T and is the factory setting for shipment 1 2 53 54 55 56 57 58 Closed Open Figure 6 50 Normal Boot switch setting Diagnostic LED The diagnostic LED located on the CPU board near the boot switch is used to troubleshoot CPU kernel problems if the VM700T fails to boot As the boot steps increment the LED number also increments If an error occurs the LED will flash alternately between E and a number That number indicates the failed area of the boot diagnostics A P is displayed when the boot up diagnostics all pass VM700T Video Measurement Set Service Manual 6 73 Troubleshooting Procedures Running the High Level Diagnostics You can run individual user selec
312. quire that clock to cause the bit to set then re enables the sample clock to clear the Genlock board A2 the bit be operating correctly Clamp Counters A C Checks the counter chips Performs walking 1 and walking 0 tests and Acq Sig Counters read and write and checks countdown over several reads 5100 5102 Register File State Machine Settings Checks SRUN and TRUN lines of the dynamics RAM control data Trigger and Sequence and address lines of the trigger RAM Runs a checkerboard pattern RAM test on the trigger RAM Tests state machine sequence RAM Acquisition portion of the RAM Fills RAM with psuedo random sequence then reads and verifies it Acquisition Memory A18 Successful completion of FIFO Checks that data moves through the FIFO without overflow even with these tests requires that processor bus contentions Genlock 2 Controller portion of the Acquisition Memory M8 be operating correctly Load Looping Checks that acquisition state machine can be programmed to write the contents of temporary store into acquisition memory locations and that it can process acquisition program GOTO instructions 12 Optional Hardware Pass indicates hardware present and working NA indicates hardware not available 6 80 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Table 6 4 User selectable diagnostics cont Board tested Description External Triggers Checks that Co
313. r also participates in the automatic rate detection function VM700T Video Measurement Set Service Manual 3 47 Theory of Operation Analog Signal Path Digital Signal Path SDI SDI SDI AES EBU Analog LTC ChA Ch B Output Digital Audio Ref Time Code d Equalizer Equalizer SDI AES Audio Analog LTC Receiver Regenerator receiver sync stripper High performance Clock Clock Channel i dein clock recovery recovery recovery select nes Nae synthesizer Eye Jitter select Jitter demodulator Deserializer Deserializer 4 Jitter filters waveform 10 Bit Wander Analog tine amp frame Line amp frame ADC frequency peak synthesizer synthesizer counter detectors Eye Di l Jitter Wander SUM Channel select mux flags J E g ol o E coprocessor B E 5 2 i Digital Analog 8 8 E 2 5 52 E e os g 5 3 2 3 2 gt Bus lt S 5 5 5 Functions contained in data path mux IC Audio Video Deserializer Functions contained in mux Flag selection mux Audio sample present super mux IC Y y To CPU board To Acq Ctrlr board Figure 3 20 Option 1S block diagram 3 48 VM70
314. r filters Front Bezel Air Filters POWER FAIL Status Power supply is in over Same as OVERTEMP symptom LED lit temperature shutdown Faulty monitor pulling Diagnose by disconnecting 12 V monitor supply cable down 12 V on power P3 at power supply and retrying startup If POWER supply FAIL status LED does not light with 12 V cable disconnected replace CRT module Faulty power supply Check power supply Refer to Power Supply Diagnostics in this section VM700T Video Measurement Set Service Manual 6 53 Troubleshooting Procedures Table 6 3 VM700T symptoms and corrective actions cont Symptom Corrective action Load on power supply Check power supply Refer to Power Supply Diagnostics exceeds design limit in this section No waveform display ora Loose cable connections Check cable connections Loss of Sync message in waveform mode Incorrect input signal Verify that horizontal and vertical sync signals are being incorrect H sync or V sync sent signal Signal too noisy signal Correct the cause of low S N ratio signal noise ratio below required minimum Incorrect sync source Select correct sync source selected Faulty genlock board 2 Replace the genlock board Refer to Removing and Replacing the Genlock Board Faulty acquisition memory Replace the acquisition memory board Refer to board A18 Removing and Replacing the Acquisition Memory Board Faulty analog input board Replace analog input bo
315. r tabs to disconnect the cable from the SDI board at J3 Unplug the circuit board using the ejector tab to release the board from the main interconnection board When the circuit board is loose slide it out of the card cage 2 Perform the following steps to replace the SDI board a Guide the SDI board onto the second from the top right side card cage track and slide it into the card cage connector Align the circuit board connector pins with the main interconnection board connector and press firmly to seat the connector Reinstall each of the five cables to the SDI board ensuring that they are firmly seated in the board connectors see Figure 6 12 Install the card cage retainer refer to step 4 on page 6 17 Install the cover panel refer to Cover Panel Removal and Replacement on page 6 8 SDI Rear Panel Interface Assembly As you face the front of the VM700T in the operating position the SDI Rear Panel Interface assembly A23 is located on the right side of the rear panel To remove this assembly you must first remove the right side cover and the card cage retainer so that you can disconnect four cables from the SDI board 6 20 VM700T Video Measurement Set Service Manual Maintenance Acquisition board J7 green J8 blue VM700T right side Figure 6 12 SDI board A22 cable connections rs Perform the following steps to remove the SDI Rear Panel Interface assembly
316. r the front panel processor A built in clock synthesizer generates the required system clock frequency for the front panel processor and the external interface circuitry The front panel is scanned for button presses knob rotation and touch screen touches These inputs are recorded and processed to provide the user control interface to the CPU A simplified block diagram of the CPU I O board is shown in Figure 3 6 This board handles the data flow between the CPU and the two serial RS232C ports and one parallel printer port The parallel printer ports has a dual purpose besides being the printer output port it acts as an input port when used to upload new firmware to the Flash EPROM PD lt 31 0 gt PORT 0 PA 31 0 Serial Port 0 Interface BOATS Parallel Port Print Interface Connector Address and CPU Data Buffers Bus Control A 32 Bit Counter Figure 3 6 CPU I O board block diagram There are two DB9 RS 232 serial communication ports Of the nine pins in the connector pins 6 and 9 are not connected The remaining pins are in the standard configuration for a DB9 RS 232 DTE serial connector as shown in Table 3 1 VM700T Video Measurement Set Service Manual Theory of Operation Table 3 1 Signals used by VM700T RS 232C ports 1 DCD Data Required for modem connections only This signal typically comes Carrier Detect from a modem and indicates that a phone connection is made 2 RD Receive The VM700T rec
317. r you make the adjustment requested and store the current setting a second set of instructions are displayed as shown in Figure 6 45 Follow the directions given in the screen TOUCH PANEL INTERFACE CAL DISPLAY Use the knob to adjust horizontal position and squareness of the screen border lines Press AUTO button to abort or any other to accept and store current setting Current Setting 8 Figure 6 44 Touch screen calibration display TOUCH PANEL INTERFACE CAL PANEL press AUTO to abort TOUCH THE DOT INSIDE THE SQUARE Place finger tip directly over the dot being careful to avoid parallex Keep touching the dot until the square highlights and beeper sounds SQUARE LOCATIONS SEQUENCE Screen SQUARES will appear near the screen corners 1 2 SEQUENCE will be 3 4 1 2 3 4 as indicated to the right Figure 6 45 Touch screen calibration panel VM700T Video Measurement Set Service Manual 6 69 Troubleshooting Procedures Setting the Power Up Mode 6 70 7 After you have touched the dots at all four corners a screen displaying some typical panel calibration factors is displayed as shown in Figure 6 46 From that screen you can press any key to return to the VM700T startup menu PANEL CALIBRATION VALUES XSCALE 471 XOFFSET 292 YSCALE 398 YOFFSET 231 Press Any Key to Continue NOTE Panel calibra
318. racy of certain frequencies and levels is important to your application we recommend that your test procedure include those frequencies and levels Table 4 5 lists audio option accuracy and flatness specifications Table 4 5 Accuracy and flatness specifications Accuracy Frequency Range Level Range includes flatness Flatness 20 40 Hz gt 20 dBu 0 3 0 2 dB 0 1 0 2 dB 20 dBu to 50 dBu 0 4 0 3 dB 0 1 0 2 dB 50 dBu to 60 dBu 0 6 0 5 dB 0 2 0 3 dB 60 dBu to 70 dBu 1 0 dB 0 4 0 5 dB 40 Hz 20 kHz gt 20 dBu 0 1 dB 20 dBu to 50 dBu x 0 1 dB 50 dBu to 60 dBu 0 2 dB 60 dBu 70 dBu x 0 4 dB Level difference between channels is 0 2 dB at levels of 50 dBu and greater 1 Power on the VM700T and associated test equipment and let them warm up for 20 minutes 2 Connect the sine wave generator to the Option 41 audio input connector as in Figure 4 8 3 Press the Measure hard key select Audio and run the audio analyzer measurement VM700T Video Measurement Set Service Manual Audio Option 41 Triple Input Verification Procedure j To Option 41 audio input connector wel Figure 4 8 Option 41 cable connections level accuracy and flatness check 4 Using a known accurate sine wave generator or one verified with an accurate AC voltmeter apply a 120 Hz input to the Audio option at ampl
319. rames or whatever the application needs to count Dynamic Address Latch The 11 bits received by this address latch are clocked through to the dynamic settings static RAM These are the same 11 address bits that are returned to the address register from the output of the sequencer static RAM but delayed one clock cycle Control Word Latch The control word latch holds a three bit control word issued to the data acquisition section of the board These control bits cause the program counter in the data acquisition section of the board to jump to preset addresses Dynamic Settings This circuitry sends additional front end control data to the Analog Input Genlock and Filter Switch boards The key requirement for this block is that its outputs must be able to change rapidly because offset gain dither input selection and filter selection may change many times during a single line of video The CPU microprocessor can access the dynamic settings static RAM any time even during an acquisition The same control bit SRUN that disables the sequencer static RAM determines if the microprocessor access requires synchronization Six of the eight bits sent to the dither generator are used as data the other two are for control The dither generator s four control states are the following clear W sequence to the next dither level VM700T Video Measurement Set Service Manual 3 25 Theory of Operation 3 26 W hold the current leve
320. ration Interconnection Diagram The interconnection diagram shows the connections made between modules to assist in tracing the signal and power distribution routes VM700T Video Measurement Set Service Manual 9 1 Diagrams 9 2 VM700T Video Measurement Set Service Manual SDI Ch SDI Ch B gt SDI Output lt _ Analog Ref gt PE AES EBU Digital Audio LTC Time Code gt ChA gt 12 A13 Ch 4 GPIB Port Analog video to ADC ChA ChB Video to filter switch A3 ADC A4 Filter switch Filtered video Ch C Ext Sync Video to genlock Amplifier control Mode control Filter select and control bus A23 A22 A18 SDI Option SDI Acquisition Interface Option memory Data and control bus Data bus A2 Genlock Frame line and sample check Control bus Control bus Control bus A11 Main interconnect left and right Supply voltages Alarm signals Audio Option A15 Power supply A16 A19 ON OFF VM700T Video Measurement Set Service Manual GPIB Option O PS fail O Over temp O Power 14 Display monitor Video V Sync Sync c Touchscreen B050100 amp above A10A2 Touchscreen Keyboard below 050100
321. ration as repair guide VM700T Video Measurement Set Service Manual 6 51 Troubleshooting Procedures Table 6 3 VM700T symptoms and corrective actions Symptom Corrective action No display blank screen Faulty power supply Check power supply Refer to Troubleshooting the Power Supply Faulty CRT Connect a VGA monitor to the rear panel VGA connector and check for a display If the VGA signal is good replace the CRT display assembly Refer to Removing and Replacing the CRT Assembly Loose Cables Check for loose AC line cord CRT connector or power supply connections To gain access to the CRT connector refer to Removing and Replacing the CRT Assembly To gain access to power supply connections refer to Removing and Replacing the Power Supply Blown mains line fuse Check fuse on rear panel Refer to Troubleshooting the Power Supply Faulty CPU board A5 Check the CPU board Diagnostic LED Refer to the diagnostic LED display on page 6 73 Replace the CPU board Refer Removing and Replacing the CPU Board This action requires a complete reprogramming for the replacement CPU Glitches and spikes in Faulty ADC board A3 Replace ADC board Refer to Removing and Replacing Waveform mode the ADC Board Faulty acquisition memory Replace the acquisition memory board Refer to board A18 Removing and Replacing the Acquisition Memory Board Faulty analog input board Replace the analog input board Refer to Removing and
322. rds m Flat blade screwdriver 3 16 or 1 4 blade W Pozidrive screwdriver 1X Procedure Use the following procedure to remove and replace the Audio boards l Perform the following steps to remove the Audio boards a Remove the left side cover panel refer to Cover Panel Removal and Replacement on page 6 8 b Remove the retaining screw from the card cage center support and remove the center support from the card cage see Figure 6 3 on page 6 10 VM700T Video Measurement Set Service Manual 6 11 Maintenance c Remove the circuit board retaining screw from the appropriate circuit board NOTE It may also be necessary to remove or loosen the circuit board retaining screw immediately above the circuit board you are removing d If you are removing only one of the audio option boards disconnect the flat cable between them at J9 e Unplug the circuit board using the ejector tab to release the board from the main interconnection board Remove the board from the card cage 2 Perform the following steps to install the Audio boards a Guide the audio boards onto the card cage track and slide it into the card cage connector see Figure 6 4 b Align the circuit board connector pins with the main interconnection board connector and press firmly to seat the connector c Replace the circuit board retaining screw d Replace the circuit board center support and screw e If you disconnected the flat cable
323. readout is 9 to 18 dB Check that the Timing p p readout is 490 to 1320 ps Check that the Alignment p p readout is 490 to 1320 ps VM700T Video Measurement Set Service Manual 4 33 SDI Option 1S Verification Procedure Interchannel Timing Application 4 34 Perform the following procedure to check the SDI Interchannel Timing application l Perform the following steps to check the digital to analog mode of the SDI Interchannel Timing application NOTE The measurement reading you make in step e of this procedure assumes you are using the Tektronix TG2000 Signal Generation Platform for this check For VM700T firmware version 980422 and below there is a built in timing offset of 224 4 usec For VM700T firmware version 990512 and above there is a built in timing offset of 2 0 usec a Connect an NTSC black burst signal to the Option 1S Analog Ref input Terminate the Analog Ref loopthrough using a 75 2 terminator b Replace the 360 Mb signal on the SDI Ch A input with a 270 Mb 525 line 10046 color bars signal Leave the SDI Ch A input terminated with the high frequency terminator c Press the VM700T front panel Measure button and then touch the SDI IC Timing soft key d Press the front panel Menu button and then touch the Relative Analog soft key e Check the interchannel timing measurement reading m VM700T firmware version 980422 and below 224 0 to 224 8 us m VM700T firmware version 990512 and ab
324. ring power up Power Up Mode when selected displays the Change Run Mode soft key Touching the Change Run Mode soft key returns you to the SELECT RUN MODE screen diagnostics can be bypassed or configured to run in normal power up mode When configured to run all the tests for that diagnostic are run completely through and the display returns to the initial Diagnostic menu unless an error is found VM700T Video Measurement Set Service Manual 6 75 Troubleshooting Procedures Power Up Mode displays a line for each family of tests that passes If any of the tests within the family fail the program halts at the failed main test and shows the test block that failed All the subtest titles are shown in the test block with any that failed marked with FAIL Passed subtests are marked with Pass There two additional soft keys labeled Continue and Rerun Test displayed on the screen Continue resumes the diagnostic Rerun Test repeats execution of the test family Certain of the diagnostics will also display the message Automatically Continues in 60 Seconds after a failure and count down as the time elapses NOTE The powerup function key will not run at power on when GPIB is selected as the remote control port When all the tests within a diagnostic routine have been completed the Select Run Mode screen is displayed From the VM700T Diagnostics Startup menu select R INSTRUMENT RUN MODES This brings up a second menu the INSTR
325. river 3 16 or inch blade W Pozidriv screwdriver 1X Procedure Use the following procedure to remove and replace the I O board l Perform the following steps to remove the I O board a Remove the left side cover panel refer to Cover Panel Removal and Replacement on page 6 8 Remove the retaining screw from the card cage center support and remove the center support from the card cage see Figure 6 3 Remove the circuit board retaining screw from the I O board NOTE It may also be necessary to remove or loosen the circuit board retaining screw immediately above the circuit board you are removing d Unplug the I O board using the ejector tab to release the board from the main interconnection board and remove the board from the card cage 2 Perform the following steps to replace the I O board a Guide the board onto the card cage track and slide it into the card cage see Figure 6 4 Align the circuit board connector pins with the connector on the main interconnection board and press firmly to seat the connector Replace the circuit board retaining screw Replace the circuit board center support and screw Replace the cover panel refer to Cover Panel Removal and Replacement on page 6 8 VM700T Video Measurement Set Service Manual 6 9 Maintenance Figure 6 3 Removing the left card cage center support Figure 6 4 Installing the I O board in the card
326. rizontal deflection circuitry to drive the trace on the raster scan CRT a video amplifier the high voltage circuitry and the CRT in a complete assembly A simplified block diagram is shown in Figure 3 12 The Video Amplifier amplifies the incoming video signal to levels necessary to drive the CRT cathode A input circuit provides impedance matching and current drive to the output video amplifier The output video amplifier drives the CRT cathode As the input video signal is increasing in amplitude the inverted video signal drives the cathode negative with respect to its 55V reference level thereby causing the beam current to increase The incoming 12 V is filtered to provide the 12 V supply A second 12 V 12 V1 is obtained through R295 That voltage is applied to a 5 V zener diode to supply a 5 V source The vertical deflection circuit provides the drive current to the vertical deflection yoke A free running oscillator circuit produces a ramp signal and an amplified vertical deflection signal The basic frequency of the oscillator is set to 60 Hz by the adjustment of the VERT HOLD potentiometer The length of the ramp signal and consequently the vertical synchronization is set by the V Sync signal When the V Sync is received the vertical ramp is terminated and a new one begins The RAMP OUT amplified to drive the vertical deflection yoke The vertical height of the display is set by the adjustment of the Vert Size potentiom eter
327. rming these procedures we recommend that you run the audio option diagnostics to ensure that the Audio Processor and Audio Analog boards are working properly Refer to the VM700T Option 01 NTSC amp Option 11 PAL User Manual or the VM700T Video Measurement Set Service Manual for information on how to select and run the Audio Option diagnostics NOTE Performing the following procedures requires the fabrication of non standard adapters and cables These are used to connect a sine wave generator to the VM700T audio option The following list of test equipment describes the cable ends needed except for the provided female XLR to male mini XLR adapter cable locating the components and fabricating the cables is the responsibility of the user Test Equipment Required The test equipment needed to perform the verification procedures is listed in Table 4 2 Test equipment suggestions for use in doing the verification procedure are given in the example column The examples given are based on the test equipment that many customers and the Tektronix service centers have installed for supporting the VM700 family of video measurement sets Substitute test equipment may be used if available Refer to the Minimum Specification column to determine the key specifications needed to verify the accuracy of the VM700T Video Measurement Set Audio option VM700T Video Measurement Set Service Manual 4 13 Test Equipment Depot 800 517 8431 99 Washington S
328. rogram memory is stored in Flash EPROM Programming of the Flash EPROM is possible through the parallel printer port for system upgrades Byte word 3 bytes and long word access are allowed in read mode Writes are restricted to long word access during device programming The memory defaults to read only at power up or after a system reset DRAM This is the microprocessor s working memory space Memory sizes of 4 8 or 16 Megabytes in SIMM boards are supported A dynamic RAM controller provides the interface between the dynamic RAM and the CPU microprocessor Real Time Clock single time keeper device provides a real time clock alarm watchdog timer and interval timer Display ASIC and VRAM display ASIC application specific integrated circuit processes the display information and prepares it for display The video RAM is divided into eight bit planes display memory layers Data to be displayed is loaded in the video RAM Data is then read out of the VRAM as required for the display updates Refresh information is written into alternate bit planes as the display data is being read from the active bit plane A VGA output from the display system permits viewing the display on an external VGA monitor The VGA connector is located on the back panel of the VM700T VM700T Video Measurement Set Service Manual 3 17 Theory of Operation Front Panel Processor CPU I O Board A20 Serial Ports A 32 bit microcontroller is used fo
329. ronix DM 502A or equiv 200 V 3 1 2 digit display adjust CalDac alent VM700T Video Measurement Set Service Manual 5 1 Adjustment Procedure Table 5 1 Test equipment required for verification and adjustment cont Equipment Minimum specification Example Coaxial cable 2 required 75 Q impedance high Signal interconnections Tektronix part number quality noise free 1 meter 012 0074 00 length Termination 75 Q precision BNC connec Signal termination Tektronix part number tors 011 0102 01 Alignment tool Non metallic flat blade Adjust potentiometers and Tektronix part number capacitors 003 1364 00 Screwdrivers Pozidriv 1X and 2X Remove and replace cover panel screws Gain phase analyzer 75 Q impedance Extended flatness adjust Hewlett Packard 4194A ment Impedance Gain Phase analyzer Feed through termination 75 Q impedance BNC Signal termination Tektronix part number connectors 011 0055 01 Adapter 2 required BNC female to SMB male Signal interconnections for Omni Spectra part number snap on connector extended flatness adjustment 3280 2224 00 1 The example amplitude calibrator requires a TEGAM TM500 or TM5000 series power module 2 The flatness accuracy required of the leveled sine wave generator is only to the bandwidth needed to perform the VM700T verification and adjustments It is not specified to be that flat over the entire bandwidth of the generator 3 Omni Spectra is a MACOM company 140 Fourth Avenue
330. ront Panel hardware Abi Note DVM inputs are not shown 6 79 Troubleshooting Procedures Table 6 4 lists and describes the VM700T high level diagnostic tests Additional diagnostics are added to this list with the addition of the hardware options GPIB Interface and Audio Measurements Table 6 4 User selectable diagnostics Board tested Description Genlock A2 Status Checks Verifies that the Genlock status register correctly represents the hardware configuration These tests must pass to run the lock tests 2 NTSC or PAL VCO Checks the ability of the Genlock A2 to acquire and hold lock using Lock each VCO The test forcefully breaks lock by toggling rapidly between internal and external sync with the genlock configured for the opposite standard Then the genlock is configured for the standard being tested and time to lock is measured Controller portion of the 3 Acquisition Memory A18 Control Registers Checks mode Genlock configuration Genlock status and filter control registers with 8 bit walking 1 and walking 0 patterns Checks analog input register for writeability no bus errors Checks DVM readback register for readability Overrange Detector Checks bit 4 of the Controller interrupt register ADC output is latched high to force the bit to set and latched low to clear it Successful completion of 5 Clock Detector Checks bit 2 of the Controller interrupt register Disables the sample these test re
331. rred to as low level those that run as applications executed by the operating system are referred to as high level The instrument pauses noticeably when the operating system is booting so messages are displayed indicating when this boot is occurring to aid the user in differentiating between high level and low level diagnostics Grouping of diagnostics within the two sets is by circuit board Within a circuit board diagnostic are one or more tests associated with each test is a main pass fail result and where applicable one or more sub results The purpose of this format is to present all the information used within a test to determine its ultimate pass fail status There is another diagnostic tests grouping the Overall Run mode The three choices are Power Up mode Auto Reset mode and User Interactive mode These are discussed later in this section in Selecting an Overall Run Mode on page 6 61 Diagnostics are normally bypassed for a quicker startup but they can be configured to run automatically during a normal instrument powerup The normal powerup mode skips all diagnostics Power up modes can be selected using hardware boot switch settings on the CPU board discussed later in this section or in some cases by pressing and holding certain front panel buttons during powerup referred to as backdoor boot modes For example holding the Menu button in while turning on the power causes the 7 to enter the low level diagnostic int
332. rs VCR When timing measurement precision is most important or when greater timing resolution is desired the strobe may be exactly 20 25 MHz 20 25 MHz sampling mode This mode of operation eliminates the small timing errors inherent in phase locked loop systems In addition the genlock board sends line and frame sync strobes to the ADC board Sync Stripper sync stripper removes all luminance and chrominance information from the baseband composite video signal but leaves the horizontal and vertical sync information The sync stripper provides this information on its horizontal sync and composite sync combined horizontal and vertical sync outputs Video signals from VCRs sometimes contain only rudimentary vertical sync information which can cause the sync stripper to mis trigger A 200 microse cond delay allows the sync stripper to function properly in the presence of this kind of vertical sync Some countries place digital audio on the horizontal sync pulse using sound in sync SIS A menu selection in the waveform application engages circuitry in the sync stripper to sustain good performance in the presence of SIS Crystal Oscillator temperature compensated crystal oscillator provides a 20 25 MHz clock with 5 parts per million ppm accuracy It is divided to either an NTSC or PAL line rate frequency and used as one of the selections for the phase locked loop reference clock It is also used as the sampling strobe in 20 2
333. s the instrument completes its power up procedure Press the front panel Configure button If necessary set the VM700T to Digital Mode using the Mode soft key Touch the Configure Files soft key and then touch the Source Selection Digital soft key Use the front panel knob to highlight the Digital A line and then touch the highlighted line to cause a box to appear around the current selection Turn the knob to select 270MB 525 line and then touch the Accept Input soft key Touch the Update amp Exit soft key to exit the configuration file Figure 5 10 Loosening the right side cover VM700T Video Measurement Set Service Manual 5 23 Adjustment Procedure Adjustment Procedure 5 24 Perform the following procedure to adjust the Option 1S hardware NOTE The VM700T and the Option 1S hardware must be warmed up for at least 20 minutes before you perform any adjustments l Perform the following steps to adjust the SDI Eye Diagram application gain and offset a Remove all signal cables and terminators from the Option 1S inputs b Press the VM700T front panel Measure button and then touch the Diags soft key c Use the front panel knob to scroll through the on screen selections and then touch the SDI Calibration soft key d Touch the Eye soft key should be highlighted and then touch the Calibrate soft key e Check that the displayed New Data values are within the limits shown in Table 5 5
334. s After installation the rack slides may bind if they are not properly adjusted To adjust the slides slide the instrument out about 10 inches slightly loosen the screws holding the slides to the front rails and allow them to seek an unbound position Re tighten the screws and check the tracks for smooth operation by sliding the instrument in and out of the rack several times To fasten the instrument securely in the rack tighten the knurled retaining screw Rack Slide Maintenance rack slides do not require lubrication The dark gray finish on the rack slides is a permanent lubricated coating Knurled retaining screw To install 1 Pull the intermediate track sections to the fully extended position 2 Insert the instrument chassis sections into the intermediate sections 3 Press the stop latches and push the instrument toward the rack until he latches snap into the holes 4 Again press the stop latches and push the instrument fully into the rack 3 5 Tighten the knurled retaining screw Knurled retaining screw To remove 1 Loosen the retaining screw and pull the instrument outward until the stop latches snap into the holes 2 Press the stop latches and remove the instrument Figure 6 30 Installing and removing the VM700T from the rack 6 48 VM700T Video Measurement Set Service Manual a eee Troubleshootin
335. s effectively identify failures to the Acquisition Controller board the SDI to Acquisition Con troller interconnect and the SDI specific hardware when signal sources are connected as shown in Figure 6 67 Most SDI specific hardware errors occur on the SDI board NOTE The analog measurements of the VM700T are still usable if the Option 1S diagnostics fail but the VM700T passes the rest of the diagnostics Like the other VM700T user selectable diagnostics the Option 1S diagnostics can be configured to run at power up on demand or in a continuous loop when Option 1S is installed in the VM700T The following procedure provides instructions on how to connect signals to Option 1S in order to perform the full set of option diagnostics The diagnostics do not verify any specifications but they do provide a high level of confidence that the option is working properly Table 6 13 lists the Option 1S diagnostic tests To verify instrument operation to published specifications refer to the SDI Option 1S Performance Verification on page 4 25 VM700T Video Measurement Set Service Manual Troubleshooting Procedures 1 1 0 SDI SDI Acq Cont Interconnect Interconnect New RE Acquisition Board m n SDI Board 1 Caroler Channel A Board Ribbon cable Channel B SDI Output LTC PSS SSS SDI Specific Hardware Figure 6
336. s lines are decoded to provide the various control bits used throughout the audio option boards Several address decoders are used One decodes data intended for the Audio Processor board another decodes the P X and Y memory program memory and the X data and Y data memories A third decodes the control registers on the Audio Processor board and the interrupt control signals for both the CPU and the DSP The bus buffers are enabled during bus to bus accesses They are disabled to isolate the busses when bus to bus accesses are not being done The address buffers are unidirectional devices that feed the Audio Processor address to the DSP address bus VM700T Video Measurement Set Service Manual Theory of Operation Interrupt Generator Status Port A function of this 32 bit control register is to control interrupts for the DSP digital signal processor It consists of an interrupt generator data buffers and read write registers that hold the data for access when needed Interrupt Generator interrupt generator contains the interrupt control lines for the DSP The interrupts are generated by audio data When enabled left channel audio data and right channel generate separate interrupts to keep the channel data separated for processing Data Buffers There are several data buffers One data buffer holds the interrupts the interrupt enables and the channel data indicator The channel data indicator is used to indicate which chan
337. s procedure verifies flatness and measurement accuracy by checking signal levels at specified frequencies NOTE The actual frequencies and levels checked are not specified in this procedure If the measurement accuracy of certain frequencies and levels is important to your application we recommend that your test procedure include those frequencies and levels Table 4 3 lists audio option accuracy and flatness specifications Table 4 3 Accuracy and flatness specifications Accuracy Frequency range Level range includes flatness Flatness 20 40 Hz gt 20 dBu 0 3 0 2 dB 0 1 0 2 dB 20 dBu to 50 dBu 0 4 0 3 dB 0 1 0 2 dB 50 dButo 60dBu 0 6 0 5 dB 0 2 0 3 dB 60 dButo 70 dBu 1 0 dB 0 4 0 5 dB 40 Hz 20 kHz gt 20 dBu 0 1 dB 20 dBu to 50 dBu 0 1 dB 50 dBu to 60 dBu x 0 2 dB 60 dBu to 70 dBu x 0 4 dB Level difference between channels is 0 2 dB at levels of 50 dBu and greater 1 Power on the VM700T and associated test equipment and let them warm up for 20 minutes 2 Connect the sine wave generator to the VM700T audio option left and right mini XLR input connectors See Figure 4 6 for an example of cabling VM700T Video Measurement Set Service Manual 4 15 Audio Option 40 Verification Procedure NOTE For this connection you may want to use the two female XLR to male mini XLR adapter cables supplied with the VM700T
338. s the front panel Menu button and then touch the Measure soft key Touch the following soft keys if necessary to turn the measurements on soft keys will be highlighted Meas Box Eye Amplitude Rise Fall Times and Rise Time Adjusted NOTE For the SDI Output check the Average function must be turned off Use the front panel Average button to turn off the Average function 10 Check that the Amplitude readout is 720 mVolts to 880 mVolts 11 Check that Risetime and Falltime readouts are both 400 pSec to 800 pSec 12 Remove all cable and terminators from the VM700T VM700T Video Measurement Set Service Manual 4 35 SDI Option 1S Verification Procedure 4 36 VM700T Video Measurement Set Service Manual EEE NEN Adjustment Procedure The procedures in this section may be used if performing the Verification procedures determines readjustment is needed Additionally after a board exchange certain adjustments may be needed to compensate the overall system performance Follow the directions found in the adjustment procedures when readjustment is needed Test Equipment Required The test equipment to use for performing the system level adjustment procedures is shown in Table 5 1 Test equipment suggestions for use in doing the verification procedure are given in the example column The examples given are based on the test equipment that many customers and the Tektronix service centers have installed for supporting the VM70
339. sary to match the the stored trace 19 Remove the gain phase analyzer cable from the channel C connectors On the VM700T select A for channel A input 20 On the gain phase analyzer return to the main menu Press Recall A to remove the stored trace C922 affects this area ofthe curve on all 3 channels A Adjust C922 for best flatness on all channels B Bandpass is too low Adjust the Input C for the affected channel C Bandpass is too wide and peaked Adjust C436 and D Typical correct flatness curve All points curve within C335 for best flatness on all channels 30 mdB to 8 MHz Figure 5 7 Example gain phase analyzer flatness waveforms 5 18 VM700T Video Measurement Set Service Manual Adjustment Procedure 21 Reinstall the cables and jumpers removed in step 9 to their original positions but leave the SMB cable between the Analog Input board and the ADC board disconnected 22 Set the marker on the gain phase analyzer to 6 MHz and check that the frequency response is flat within 30 mdB peak to peak see Figure 5 7 NOTE If the VM700T meets the limits described in step 16 skip step 17 23 If the frequency response is outside the limits specified in step 16 adjust C436 on the filter switch board to bring it into specification Re verify that all channels meet specification after adjusting C436 Capacitor C335 may also require adjustment to attain the pro
340. sconnect the power bus cable at its five connectors and then remove the cable Remove the five board retaining screws and carefully lift the board from the VM700T chassis 2 Perform the following steps to replace the ADC board a Carefully place the board in the chassis and onto the bulkhead standoffs be sure the cable extends out the side of the chassis Install the five board retaining screws Install the cable on its connector at J6 on the Acquisition Memory board Install the flat 10 conductor cable between J6 on the Genlock board and J111 Install the shielded cable at J765 on the ADC Filter board VM700T Video Measurement Set Service Manual Maintenance J6 Al E Y O O fl l zx i Power i bus cable ag Santa J765 EIN VM700T to
341. se Proper Power Cord Use only the power cord specified for this product and certified for the country of use Use Proper Voltage Setting Before applying power ensure that the line selector is in the proper position for the power source being used Ground the Product This product is grounded through the grounding conductor of the power cord To avoid electric shock the grounding conductor must be connected to earth ground Before making connections to the input or output terminals of the product ensure that the product is properly grounded Observe All Terminal Ratings To avoid fire or shock hazard observe all ratings and markings on the product Consult the product manual for further ratings information before making connections to the product Do Not Operate Without Covers Do not operate this product with covers or panels removed Use Proper Fuse Use only the fuse type and rating specified for this product Avoid Exposed Circuitry Do not touch exposed connections and components when power is present Do Not Operate With Suspected Failures If you suspect there is damage to this product have it inspected by qualified service personnel Do Not Operate in Wet Damp Conditions Do Not Operate in an Explosive Atmosphere Keep Product Surfaces Clean and Dry Provide Proper Ventilation Refer to the manual s installation instructions for details on installing the product so it has proper ventilation VM700T Video Measurement Set
342. sed to communicate between the processors Besides the shared memory spaces the GPIB processor has some private RAM space that is not directly accessible by the VM700T processor The private RAM space is used by the GPIB processor as stack space to hold local variables and intermediate results Another section of the memory space is the program RAM area It is treated as ROM space by the GPIB processor and cannot be written to by the GPIB processor The operating code for the GPIB board is store in the ROM of the VM700T On initialization a copy of that code is loaded into the program RAM space of the GPIB processor by the VM700T processor It is not possible for the two processors to access the shared memory at the same time Either one or the other processor can access the shared RAM space or the IPC register Both the shared RAM and the IPC register share the same controlling hardware The Dual Port RAM controller has arbitration circuitry that controls accesses to the shared memory space to prevent contention When both processors are accessing the shared space this circuitry alternates accesses so neither processor blocks the other from the shared memory space 3 44 VM700T Video Measurement Set Service Manual Theory of Operation J100A B C to VM700T D0 31 VM700 Main VM700 Main Processor Decoding Processor Dual Port Memory Interface D0 31 BA0 25 VM700 Main
343. sing a precise 1 000 volt reference and ground Successful completion of these tests requires that the Genlock A2 and Acquisition Memory A18 boards be oper ating correctly DC Paths Checks that a nominal DC voltage can be routed through each input channel to the ADC Checks gain control range and bit weights Calibration DAC Checks the range and bit weights of the calibration DAC Offset Control Checks the range and bit weights of the offset control DAC Input Selection Checks the input selection switch by setting the channel bias DACs to different levels on each channel and measuring the net bias for each switch setting 4 Bias Control Range for Checks bias control DAC for range and bit weights Verifies each DAC each channel for independence by changing the other two and monitoring the one being tested to verify that its range and bit weight remain unchanged n2 lt VM700T Video Measurement Set Service Manual 6 81 Troubleshooting Procedures Table 6 4 User selectable diagnostics cont Board tested Description 25 Clamp for each Checks clamp level DAC for range and bit weights Verifies each DAC channel for independence by changing the other two and monitoring the one being tested to verify that its range and bit weight remain unchanged Measures fast and slow clamp response time by timing a 100 mV clamp level change Verifies fast clamping at each possible clamp pulse width Fil
344. ssemblies Cover panel m I O board m Option 40 and Option 41 audio boards m Option 41 connector installation m Option 48 GPIB Interface board CPU board Acquisition Memory board Option 1S SDI board m Analog Input board m Genlock board m ADC board Filter Switch board Display and control components m Power supply Interconnect board VGA board and cooling fan page 6 8 page 6 9 page 6 11 page 6 12 page 6 14 page 6 15 page 6 18 page 6 19 page 6 23 page 6 25 page 6 28 page 6 30 page 6 32 page 6 38 As you face the front of the VM700T in its operating position the CPU A5 is located in the right side card cage along with the Acquisition Memory A18 The I O board and any of the hardware option boards are located in the left side card cage The analog section boards Analog Input A1 Genlock 2 and Filter Switch A4 are mounted with screws and standoffs on a bulkhead under the top cover panel see Figure 6 1 VM700T Video Measurement Set Service Manual Maintenance 6 7 Front ofthe gt instrument Figure 6 1 Locating the major standard assemblies VM700T Video Measurement Set Service Manual Maintenance Cover Panel Removal and 6 8 Replacement Most of the VM700T circuit boards may be accessed by first removing three sheet metal panels that cover the top and two sides of the instrum
345. stment The Horiz Position control adjusts the fine position of the active picture area within the raster scanned width VM700T Video Measurement Set Service Manual Theory of Operation High Voltage high voltage supply provides the CRT anode voltage the focus voltage and the 55 V and 100 V sources The main focus voltage is set by the FOCUS potentiometer Dynamic focusing optimizes the edge focusing of the CRT The dynamic focusing waveform is shaped to produce the best edge focus in conjunction with the setting of the FOCUS pot for best overall focus Trace Rotation Trace Rotation circuit drives a separate deflection coil on the neck of the CRT The adjustable voltage from the trace rotation potentiometer provides an overall adjustment range for trace rotation of approximately 3 4 Power Supply A15 The power supply is composed of a primary rectifier the inverter switching circuit 12 V and 15 V regulators alarm sensing circuitry that monitors for overvoltage overcurrent and over temperature conditions and the alarm logic circuitry that shuts down the inverter switching circuitry in the event of a problem A simplified block diagram is shown in Figure 3 13 Input Power Rectifier Input Power Rectifier receives the mains AC voltage and rectifies it to provide the drive power to the inverter switching circuitry line voltage switch sets the supply to operate on a nominal voltage of either 115 VAC or 23
346. surement Set Service Manual Troubleshooting Procedures Diagnostics Menu Overview An overview of the VM700T Diagnostics Menus is shown in Figure 6 31 and Figure 6 32 Figure 6 31 illustrates the various configuration menus and utilities that are available in the diagnostics routines Figure 6 32 illustrates the low level diagnostic tests and the various configura tion menus for setting up and running the diagnostic tests Press and Hold Menu Button at Power On release it after two beeps Low Level To Low Level Low Level Diagnostics Diagnostics Diagnostics VM700T Startup Menu 7 Diagnostics Utilities Configuration Menu Power Up Error Log Set Diags Mode Utilities Powerup Mode NVRAM Utilities Instrument Run Modes Diagnostics Calibrate Help Touch Panel Menu Interface Instrument Powerup Modes Set List Diagnostic Intensity PowerUp Diags Diagnostic Quick Start Reprogrm Front Panel Set Low Level Buttons Diags Console Baud Rate Firmware Date Code Low Level Diags Loop Instrument High Level ID Number Debug Reset SW Option Key Auto Reset Use Abort or press the Auto button to back up the tree to the VM700T Startup Menu Figure 6 31 VM700T diagnostics menus overview VM700T Video Measurement Set Service Manual 6 57 Troubleshooting Procedures From VM700T Low Level Diagnostics Startup Menu Low Level Diagnostics Main Board
347. t Abort Menu Input your selection Figure 6 33 VM700T startup menu In the VM700T Startup Menu highlight the D Low Level Diagnostics Menu and press the Select Line button again This displays the Low Level Diagnostics menu shown in Figure 6 34 VM700T Video Measurement Set Service Manual 6 59 Troubleshooting Procedures 6 60 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection LOW LEVEL DIAGNOSTICS Select a diagnostic to execute from the list below Key Selection Main Bd CPU Diagnostics Main Bd Display Diagnostics Main Bd Fr Pnl Infc Diagnostics I 0 Board Diagnostics Optional GPIB Board Diagnostics Optional Audio Board Diagnostics VOW gt Reprint Abort Menu Input your selection Figure 6 34 Low level diagnostics menu The low level diagnostics consists of sets of tests that check the CPU central processing unit including the display system and the front panel interface and the I O board circuitry With the addition of the optional hardware for GPIB or Audio low level diagnostics are provided to test that hardware These tests are bypassed at normal power on unless they are configured to run by the user Usually this power up running of diagnostics will be the only use of diagnostics for the user A service person can use the diagnostics to assist in determining if a board or board set is faulty before doi
348. t 2 Input 1 left left left 1 Figure 2 14 Option 41 Triple Input Audio input connector pin locations 2 20 VM700T Video Measurement Set Service Manual Operating Information GPIB Option 48 Signal Connections and Rear Panel The Option 48 interface connector is a standard GPIB parallel connection with pin outs adhering to industry standards for location and output signal levels GPIB Indicator LED Seven LED indicators are mounted on the GPIB board You can see them at the rear of the measurement set as shown in Figure 2 15 Use Table 2 2 to determine what a lighted lamp means and its color Table 2 2 Status indicators Label Coo Meaning when lighted LSTN Addressed to listen MLA when on TALK Addressed to talk MTA when on The LED is always on in talk only mode SRQ Service request SRQ pending when on REM Remote control active when on LOCK Red FrontPanel lockout CACT Controller active state when on SCTL System control never on Figure 2 15 GPIB board rear panel VM700T Video Measurement Set Service Manual 2 21 Operating Information SDI Option 1S Rear Panel Connections Figure 2 16 shows the VM700T rear panel with Option 1S installed Figure 2 17 shows a close up of the Option 1S rear panel 2 22 The Option 1S rear panel connectors provide the following functions The SDI Ch A input is a noninterfering loopthrough BNC input for serial digital v
349. t Selector 3 42 The Audio Analog circuit board A17A1 is identical to the A13 Audio Analog circuit board in parts and operation Option 41 provides an added circuit board A17A2 to do the input channel selection from the three audio inputs The A17A2 circuit board along with the A17A1 A13 circuit board make up the A17 circuit board assembly for Option 41 Selection of the left and right input signal source from one of the three possible inputs of Option 41 is done by a set of relays and a relay selector driver device on the A17A2 circuit board Figure 3 16 shows a simplified diagram of the left VM700T Video Measurement Set Service Manual Theory of Operation input channel switching The left and right selection relay circuits are identical in operation For brevity only the left channel operation is described here Ov A XOR B B NE XOR B XOR C gg C A Singl Three Oy ingle Rear B A XOR XOR C Left Panel 94 CH1 Channel Left input to Inputs i A17A1 CH1 COM U2 K1 4 Switching K2 signals From A17A1 Relay Selector Driver Figure 3 16 Audio Analog block diagram Source Selection Relays The contacts of one relay select between input 1 and input 2 A second relay selects either the output of K1 or the source 3L and 3L to apply to the CH1 and 1 inputs going to the Audio Analog board The relays are selected by the input select
350. t Service Manual 2 15 Operating Information Rear Panel and Connections 2 16 The rear panel shown in Figure 2 10 includes the line voltage and switching module line voltage selector fuse holder a cooling fan the signal input connectors the VGA connector the parallel printer port and the RS 232 serial ports Fan exhaust 090000000 Power Fuse ON OFF Line voltage VGA Parallel Alarm Porti Porto connector Switch selector output printer port connector RS 232 ports Figure 2 10 VM700T Video Measurement Set rear panel The following paragraphs briefly describe each of the rear panel features m Line Voltage and Switching Module The module includes the connector and filter for line input voltage the line fuse and the main power switch m Line Voltage Selector The switch selects either 115 or 230 VAC line input voltage CAUTION If you intend to operate the measurement set from a line voltage other than the voltage configured at the factory you must replace the installed fuse with a fuse of the correct rating See the label on the measurement set rear panel for fuse rating information Operating the measurement set with the wrong fuse can result in severe damage m Exhaust Fan The fan circulates cooling air to internal components The fan opening must be free of obstructions for proper ventilation VM700T Video Measurement Set Ser
351. t between the audio digital and the audio analog board are optically isolated with one exception The CLR signal entering the analog board is inverted to a CLR signal This signal turns on the 2 304 MHz DAC clock when the DAC is operating Five opto isolators isolate the signals between the boards and allow the analog ground on the audio board to float to remain ungrounded from chassis or earth ground VM700T Video Measurement Set Service Manual Theory of Operation Analog board input signals to be isolated enter the board through a buffer The buffer receives its power from the VM700T The input signals enter through two of the opto isolators each device is a dual opto isolator The signals sent from the isolators are referenced to analog board ground This means that the analog board digital ground and the digital board ground are not the same The other three opto isolators take signals from the analog board and isolate them for output to the digital board These signals associated with the A D converter are applied to a buffer to drive the opto isolators The open collector outputs of the opto isolators are pulled high in case a fault causes the lines to be undriven Synchronizer digital signals from the opto isolators are synchronized to the clock signal Counter Decoder After the signals are synchronized they go to a counter decoder circuit Two of the signals determine the state of operation diagnostics mo
352. t of the address latch allows the CPU microprocessor to access the trigger RAM The microprocessor then writes a 4 bit pattern into the trigger RAM through a 4 bit enable buffer The 13 bits 10 bits of data plus over range FRAME and LSYNC are sent to the trigger RAM and and to the data acquisition sections of the board The trigger RAM performs the actual word recognition When the micropro cessor writes an appropriate 4 bit wide pattern into the trigger RAM from a 4 bit enable buffer the four output bits change when certain ranges of input data identified by bit pattern occur The output is four bits of the 16 bit input to the sequencer Input data that could be programmed to trigger sequences may include such things as sync tape dropout or zero carrier pulses Sequencer outputs drive the dynamic settings circuitry and send control bits to the data acquisition board These control bits cause the program counter on the data acquisition board to jump to preset addresses As with the word recognition circuitry the sequencer static RAM is loaded with program information from the CPU microprocessor A bit from a control register SRUN enables address and data buffers of the system bus to have access to static RAM Sequencer Address and Data Buffers When the address buffer is enabled the sequencer static RAM can be read and written by the microprocessor from the data buffer before starting the sequencer VM700T Video Measurement S
353. t to begin a new accumulation VM700T Video Measurement Set Service Manual Theory of Operation VIDEO INPUT VIDEO CLOCK cpu gt e DATA DATA BUS INTERFACE ACQUISITION TA CPU DATA CONTROL IN CPU DSACK1 CPU INTERFACE CPU ADDRESS 16 MHZ XTAL CLOCK OUT ACQUISITION CONTROL CPU CONTROL DATA CLOCK FIFO OCCUPANCY FIFO CONTROL DSACKS MIN MAX CONTROL CPU HANDSHAKE CPU ADDRESS RAM CONTROL RAM ADDRESS CLOCK IN Figure 3 7 Acquisition circuitry block diagram VM700T Video Measurement Set Service Manual MIN MAX CLOCK IN CONTROL IN FIFO DEMULTIPLEXOR ACQUISITION DATA IN ACQUISITION CLOCK IN ACQUISITION DATA OUT CLOCK IN OCCUPANCY OUT CONTROL IN STATIC RAM RAM DATA BUS CONTROL IN ADDRESS SIGNALS TO gt CONTROL SECTION 3 21 Theory of Operation 3 22 Controller Section Bus Buffers Controller ASIC Address Decoding Output Latches and Analog Input Board Interface Clamp Counters The controller portion of the board performs the following functions controls the VM700T analog front end W receives and processes digitized data from the ADC board and passes it to acquisition memory controls acquisition patterns Figure 3 8 shows a block diagram for the controller circuitry 32 data lines and the required control a
354. table diagnostics on demand either by pressing the Measure button during normal instrument operation or by powering the instrument up with the Measure button held in The high level diagnostic test all run in the same manner To run a specific diagnostic during normal instrument operation do the following steps 1 Press the Measure button 2 Press the Diags soft key The contents of the VM700T Diagnostics directory are displayed as shown in Figure 6 51 They include the user selectable diagnostics available on power up listed in the Diagnostics Selection file the DiagsLoop routine described later in this section and the routines AdcGain Adjustment CalDAC adjustment Measure Sinewave and Measure Squarewave described in the Verification and Adjustment sections of this manual In nvram Executable Files VM700 Diagnostics ADC Acquisition Adc Gain Diagnostic Diagnostic Adjustment AnalogInput Cal Dac Controller Diagnostic Adjustment Diagnostic DiagsLoop FilterBoard GPIB Diagnostic Diagnostic Genlock Measure Measure Diagnostic Sinewave Squarewave Measure Warm Video Previous Leave Selection Directory Figure 6 51 High level diagnostics menu 3 Select the soft key of a diagnostic you want to run An initial Diagnostic Menu is shown in Figure 6 52 GPIB
355. tage Range Maximum Power Consumption Fuse Rating Style Steady State Input Current Inrush Surge Current Power Cord Description 230 VAC 10 207 to 253 VAC 50 60 Hz single phase CAT II 400 VA maximum 250 Watts with VM700T load 3 Amp 250 V Time Delay 3AG 1 5 Arms 207 VAC 1 2 Arms 2260 VAC Protected with a 3A Time Delay fuse 161 0066 09 Euro 161 0066 10 U K 1 See the VM700T Power Requirements in Table 1 5 for the operating voltage range of the VM700T without the Power Line Conditioner box inline Usethe part numbers listed above to order a new power cord for use with the VM700T Power Line Conditioner box Table 1 13 Power Line Conditioner Mechanical Characteristics Characteristic Description Size Length 7 inches 177 8 mm Width 4 55 inches 115 6 mm Height 2 67 inches 67 8 mm without the feet attached Weight 2 lbs 13 5 oz 1 29 kg Shipping weight Approximately Ibs 1 36 kg 1 10 VM700T Video Measurement Set Service Manual Specification Table 1 14 Power Line Conditioner Environmental Characteristics Characteristic Temperature Operating Non operating Humidity Operating Non operating Altitude Operating Non operating Shake Shock Description 5 C to 50 C 41 F to 122 F 30 C 54 F hr max gradient non condensing derated 1 C or 1 8 F per 1 000 ft or 305 m above 5 000 ft or 1524 m altitude 20 C to 60 C 4 F to 140 F 30 C
356. te the expected and actual values that were read back from the chip If the previous test passes then this test is run else it is set to N A Since the interface to the EDH chip U41 is a 2 wire serial interface the only point of the test is to exchange some data with the device to see if it can be written and read Consequently we write and read back the TV standard bits in the EDH chip using the 12C interface If this is successful the test passes The SDI board can be forced to drive all 10 bits in the data acquisition to low or high via special test modes This group of tests exercises this ability External signals must be connected to both channels in order to have a source of data which is not all low or high so when we force all low or high we can do so under controlled conditions For this test the diagnostic asserts the FORCE LOW signal which is an input to pin 8 on U139 U140 U141 and U43 This causes these devices to drive their outputs to the low state The a data acquisition is done and the acquisition memory checked to make sure that all the bits in the data path are low If they are the test passes Otherwise a fail is flagged and for each non zero bit a message is generated on the console The diagnostic forces all data bits from the SDI board to the high state by tri stating the data drivers in PALs U35 and U30 This allows R643 R647 R651 R655 R644 R648 R652 R656 R645 R649 R653 R657 R646 R650 R654 a
357. te the measurement set with any covers removed Refer all servicing of the measurement set to a qualified service person VM700T Video Measurement Set Service Manual 2 1 Operating Information 2 2 Changing Line Voltage Range and Fuse A Power Cord Power Line Conditioner Accessory The voltage range selection switch and fuse holder are located in the lower left corner of the rear panel see Figure 2 10 on page 2 16 The measurement set is shipped from the factory set to the operating voltage of the destination 115 VAC or 230 VAC If the setting is not correct you must change it before connecting the power cord to the power source Set the voltage range selection switch located on the rear panel of the measurement set to the correct position for operation CAUTION When changing the line voltage selector switch you must also change the fuse to provide proper protection for the operating voltage in use The 3A slow blow fuse provides the proper protection in the 230 VAC range and the 6A slow blow fuse provides protection for operation in the 115 VAC range A detachable three wire power cord with a three contact plug is provided with each measurement set for connecting to both the power source and protective ground The protective ground connector in the plug connects through the protective ground conductor to the accessible metal parts of the measurement set For electrical shock protection insert this plug only
358. ted to the console If there is no signal on Channel A as determined by checking the signal present locked bits this test will be flagged N A There is only one test in this group The SDI board is configured for a jitter acquisition The data muxes are set up to pass Channel C data through to the acquisition board and a jitter acquisition is performed The 10 data bits are checked for movement and any bits that are stuck high or low are reported to the console If there is no signal on Channel A as determined by checking the signal present locked bits this test will be flagged N A VM700T Video Measurement Set Service Manual 6 111 Troubleshooting Procedures Table 6 13 SDI Option 1S diagnostic test descriptions Cont Test name SDI Wander Path Supermux Tests 6 112 Fsyncs Lsyncs Blanking Bits Eye Flags Description This test checks the drift rate circuitry The DRIFT SRC bits 2 0 into pins 9 10 11 of U129 are set via control register 1 to route CTRL STEP into pin 13 out to the outputs DRIFT CLK 2 0 is also set to select pin 2 of U130 CHOPPER EN to the output pin 5 Following this 10000 cycles of the following sequence are performed Set U129 13 high Set U130 2 high Set U129 13 low Clock U130 2 twice This causes the counters U132 and U133 to cycle through all their states several times and for each of these states to be latched into U24 The output of U24 is routed to the data acquisition
359. ter J5 Analog Ref 1 d 200 AES EBU 2 J1 4 145 Digital Audio S T LTC Time Code S A11 Main Interconnect left and right ape vel m 246 12 V to Display Monitor jg n Jie J256 15 J254 A16 Power Supply J244 J245 J255 J253 J252 ON OFF g S J140 J1 2 2 ET J5 W252 8 Figure 9 2 VM700T Video Measurement Set interconnection diagram VM700T Video Measurement Set Service Manual DESEE SEEN Replaceable Mechanical Parts This section contains a list of the replaceable mechanical components for the VM700T Video Measurement Set The replaceable modules are also included in this parts list as well as in the Replaceable Electrical Parts List Use this list to identify and order replacement parts Using the Replaceable Mechanical Parts List The tabular information in the Replaceable Mechanical Parts List is arranged for quick retrieval Understanding the structure and features of the list will help you find all of the information you need for ordering replacement parts The following table describes the content of each column in the parts list VM700T Video Measurement Set Service Manual 10 1 Replaceable Mechanical Parts Parts list column d
360. ter Times 8 Gain Using the ADC two Cal DAC DC levels are measured with x8 gain off two more with it on and the gain is calculated from the ratio of the differences Successful completion of 27 Filter Slot n for slots 0 Slot 0 is a bypass path rather than a filter slot These tests include these tests requires that through 5 filter ID and frequency response sub tests the Genlock A2 Acquisition Memory A18 and Analog Input A1 boards be operating correctly The filter ID sub test checks instrument firmware to determine the TV standard and release version This information is used by the diagnostic to determine valid filter ID for each slot The frequency response sub test generates a psuedo square wave signal by switching channel input between A and B with each channel input clamped to a different DC level The signal is routed through the filter slot under test to the ADC acquired and analyzed Discrepan cies are displayed on screen When an empty slot is correctly identified this test displays NA 1 Each gating pattern has a different number of active video lines so the ratio of the NTSC pattern cal factor to always on pattern equals the ratio of the NTSC pattern active lines to the always on pattern number The same is true for PAL 2 Range is the arithmetic sum of the measured bit weights and bit weights are measured as the effect of toggling only the indicated bit Table 6 5 provides a cross reference between
361. the Keypad board Orienting connector J933 for installation on the Removing the CRT assembly retaining screws Removing the power supply retaining screws Removing the Interconnect board assembly retaining Removing the cooling fan Construction of rack 5 Rail detail for mounting rack slides Mounting stationary rack sections Installing and removing the VM700T from the rack VM700T diagnostics menus overview VM700T diagnostic menus overview cont VM700T startup menu Low level diagnostics menu Low level diagnostic OVERALL RUN MODE menu Custom run mode menu Build CUSTOM TEST SEQUENCE menu for display Front Panel diagnostic selection buttons Special power up boot modes VM700T Startup Diagnostic Utilities menu Clear File System Utility menu Clear CPU NVRAM Utility menu VM700T Video Measurement Set Service Manual 6 14 6 16 6 17 6 19 6 21 6 22 6 24 6 25 6 27 6 29 6 31 6 33 6 34 6 35 6 36 6 37 6 39 6 41 6 42 6 45 6 46 6 47 6 48 6 57 6 58 6 59 6 60 6 61 6 62 6 63 6 64 6 65 6 66 6 66 6 68 6 68 Table of Contents Figure 6 44 Touch screen calibration display 6 69 Figure 6 45 Touch screen calibration panel 6 69 Figure 6 46 Panel calibration values 6 70 Figure 6 47 Diagnostic configuration menu 6
362. the bezel c Carefully separate the bezel from the frame and disconnect the 5 conductor cable from the STBY ON switch d Remove the nut that holds the STBY ON switch ground strap ring terminal to the keyboard bracket and disconnect the ground strap see Figure 6 20 2 Replace the CRT bezel by performing step 1 in reverse order NOTE Use care in tightening the bezel retaining screws The threaded bezel inserts can be stripped from the bezel if the screws are over tightened 6 32 VM700T Video Measurement Set Service Manual Maintenance Figure 6 19 Locating the bezel retaining screws STBY ON Switch Use the following procedure to remove and replace the STBY ON switch l Perform the following steps to remove the STBY ON switch a Remove the CRT bezel refer to CRT Bezel on page 6 32 b From the circuit side of the STBY ON switch remove the two nuts holding the switch assembly to the bezel See Figure 6 20 c Separate the switch and its front plate from the bezel 2 Replace the STBY ON switch by performing step 1 in reverse order VM700T Video Measurement Set Service Manual 6 33 Maintenance 6 34 Key board bracket Figure 6 20 Disconnecting the STBY ON circuit board Keypad Board Assembly Use the following procedure to remove and replace the Keypad Board assembly l Perform the following steps to remove the Keypad board assembly a
363. the signal is low the 2 034 MHz is not generated The signal is generated only when diagnostics are run or when a new control word is written for changing gain or attenuation The DAC is an 18 bit D A converter Serial digital data sent by the DSP and a clock signal that is replicated by the DSP are applied to the DSP A shift register realigns the 24 bit data from the DSP so that valid data is shipped to the 18 bit DAC The DAC expects leading not trailing zeros so the shift register shifts the data six bits for proper alignment This DAC circuit is used in diagnostics discussed later The output of the DAC is a current signal is converted to a voltage signal The mainframe interconnector provides 5 V and ground from the VM700T The 5 V powers two low noise high accuracy switching supplies One supply provides 5 volts at 1 ampere the second switching supply provides 15 V and 15 V at 330 mA This floating power supply isolates the analog circuitry from possible noise sources in the VM700T power supplies The and 15 V supplies are used to provide regulated and 5V to the analog board through three terminal regulators These and 5 volt analog supplies power the A D converter and the DAC Several different grounds are used in the instrument The grounds are separated to keep ground loop signals and noises from being transferred via the grounding planes of the circuit board Option 41 Audio Analog Board 6 Balanced Inpu
364. the test numbers and test names given in Table 6 4 with the hardware components tested An X in the Test no row indicates that the hardware component given in the column head is required to be operational for the test to pass See Figure 6 55 for the hardware compo nent reference If one or more diagnostic tests fail note the hardware compo nents tested They can be located on different modules so the task is to determine which hardware component is causing the failure to occur That will isolate the problem to a specific module that must replaced to effect a repair If there is a common hardware component or components tested in the different failures suspect the module that has the common components NOTE The interdependencies between modules is very high Several modules may have to be swapped into the instrument to determine the exact module that is causing a diagnostic failure Table 6 5 is then used to determine the modules that are most probable to be the source of the failure 6 82 VM700T Video Measurement Set Service Manual Troubleshooting Procedures Table 6 5 Diagnostic test number to hardware components tested cross reference Test Test name no 18 A18b 18 A18e A18e 1 Status Checks ed Lock manis _ a e S o n Clamp Counters A C and Acq Sig Counters 5100 5102 Register File State Machine Settings Trigger an
365. the wire connecting A4 J418 to A1 J923 at the J923 end only g Atthe back of the instrument remove the screws holding the signal input connector to the instrument rear panel see Figure 6 15 h Remove the eight board retaining screws seven on the perimeter and one in the center and carefully lift the board from the VM700T chassis VM700T Video Measurement Set Service Manual 6 23 Maintenance J4 on the A18 Acquisition Memory board Power bus cable VM700T top view Figure 6 14 Disconnecting the Analog Input board connectors 6 24 VM700T Video Measurement Set Service Manual Maintenance Figure 6 15 Removing screws from the signal input connector plate 2 Perform the following steps to replace the Analog Input board a Carefully place the board in the VM700T chassis by guiding the signal input connectors through the slot in the rear panel and positioning the board on its bulkhead standoffs b Replace the eight board retaining screws and then replace the screws holding the signal input connector to the instrument rear panel see Figure 6 15 c Connect the ribbon cable at 1965 see Figure 6 14 for cable locations d Connect the wire at J132 and the shielded cable at J6 e Replace the wire c
366. tics Test name DSP program RAM DSP X data RAM DSP Y data RAM Sign extend buf Shared bus timing DSP host port Audio data reg Interrupt reg Sample dropping Description Standard RAM tests that check decoded address space size RAM segment size and integrity of address and data bus to each block of parts Tests perform a simple checker board pattern test of RAM from the 68020 with the 56001 disabled Data is read as 32 bit with the upper 8 bits masked in software Same as above Same as above Checks that the 32 bit data correctly represents 24 bit sign extended data where the up per 8 bits are the same as the sign bit The 68020 writes a long sequence of data into DSP X memory and reads it During this write and read the DSP runs code that accesses its Y and P memories The test passes if the sequence gets in and out of the memories with no errors Timing is checked for 3 cases 1 Audio interrupts to DSP disabled audio data register not accessed 2 Audio interrupts to DSP enabled audio data register not accessed 3 Audio interrupts to DSP enabled audio data register accessed Verifies the major modes of the DSP host interface These modes are used in audio ap plication software This test checks the 68020 s ability to initialize the DSP host port tests the host port handshake flag bits and tests data transfer from the 68020 to the DSP through the host port If the audio hardware revision number is less than
367. tie wrap on the cable and trim off the excess end un un ptt Figure 6 8 Ferrite forms installed on the Option 41 interconnection cable As you face the front of the VM700T in the operating position the GPIB Interface board A19 is located in a card cage on the right side see Figure 6 5 The GPIB interface option board occupies the second slot above the I O board To remove the GPIB board you must first remove the right side cover and the card cage retainer The following procedures explain how to remove the GPIB board Required Tools Use the following tools to remove the Option 48 circuit board m Flat blade screwdriver 3 16 or 1 4 blade W Pozidrive screwdriver 1X VM700T Video Measurement Set Service Manual Maintenance Procedure Use the following procedure to remove and replace the Option 48 GPIB Interface board 1 Perform the following steps to remove the GPIB Interface board a Remove the left side cover panel refer to Cover Panel Removal and Replacement on page 6 8 Remove the retaining screw from the card cage center support and remove the center support from the card cage see Figure 6 3 on page 6 10 Remove the circuit board retaining screw from the GPIB circuit board NOTE It may also be necessary to remove or loosen the circuit board retaining screw immediately above the one retaining the circuit board you are removing d
368. tion is presented in a uniform format Each line consist of fields arranged under a heading shown at the top of the instrument terminal screen The heading line looks something like the following Test measmt unit min max result A brief description of the content of each field follows In a main result the name of the test In a sub result noted by an indentation from the associated main result a description of what was evaluated to determine the main result A measured value presented in integer hexadecimal or engineering scientific notation If a value is not appropriate the field is filled with one of the following no value Ed underrange indicator gt overrange indicator The minimum acceptable value for a passing result The maximum acceptable value for a passing result In general Pass or FAIL It can also be one of the following NA not applicable not tested Test Where appropriate a description of the units of the measured value otherwise filler chars Because a rigidly formatted output excludes much useful information any main or sub result line can have associated with it one or more lines of indented commentary Whereas sub result lines are indented one level of indentation from their associated main results comments will be indented two levels from their associated main results whether they are actually associated with the main result or the sub result VM700T Video Mea
369. tions values vary greatly depending on the version of touch panel that is installed in your instrument The sample values shown are typical of an older touch panel Figure 6 46 Panel calibration values You can configure the instrument to always skip the power up diagnostics or to always run them at power up To access the diagnostics menus press and hold in the Menu button while turning on the power to display the VM700T Startup menu shown previously in Figure 6 40 on page 6 66 In the VM700T Startup menu highlight the C in the Diagnostic Configuration line and press the Select Line button This brings up the Diagnostics Configuration menu shown in Figure 6 47 In this menu highlight and select P in the Set Diagnostics Powerup Mode line to bring up the power up mode choices shown in Figure 6 48 Low Level Diagnostic Interface knob moves cursor Select Line inputs selection DIAGNOSTICS CONFIGURATION MENU Key Selection P Set Diagnostics POWERUP MODE Set Diagnostics INTENSITIES B Set Low Level Diagnostics BAUD RATE Reprint Q Abort Menu Input your selection Figure 6 47 Diagnostic configuration menu VM700T Video Measurement Set Service Manual Troubleshooting Procedures In the Set Diagnostics Powerup Mode menu shown in Figure 6 48 highlight and select O to have the instrument skip diagnostics on power up or highlight and select P to have the instrument run the diagnostics
370. to ERES a 00 09 D0 D9 SS E EE TO ACQUISITION l CKD OVERRANGE E OVERRANGE DETECTOR L FRAME OUT H LINE OUT OUTLATCH Ht LINE OUT ASYNCSET 4FSC E ASYNCRESET AFSC CLOCK CKD E D GITALGND CKD GENLOCK CC ASYNC SET js ASYNC RESET FRAME LINE OUT PULSE PIPELINE LINE OUT V FRAME OUT V FRAME OUT PES ULM GEN E RR 4 Figure 3 3 ADC board block diagram 3 12 VM700T Video Measurement Set Service Manual Theory of Operation Line and Frame Pulse and V sync from the GenLock board are applied to the Line and Frame Pipeline Pulse Pipeline The pipeline is a series of flip flops that delays the frame and line sync by the same amount as the A D converter delays the video Overrange Detector Overrange detector checks to see if the eight most significant bits of the 10 bit samples are either all 1 s or all 0 s If either event occurs Overrange is asserted for that sample Sample Clock 4FSC four times the subcarrier frequency signal from the GenLock board is used to develop the sample clocks SAMPLE CLK and SAMPLE CLK to the ADC and the acquisition clocks CKD and CKD for the acquisition con troller board The clocks to the acquisition system are connected through a 36 pin ribbon cable along with 10 bit
371. to the instrument showing the following information Owner with complete address and the name of the person at your firm that can be contacted W Instrument serial number and a description of the service required Repackaging 1 Obtain a corrugated cardboard carton whose inside dimensions are at least six inches greater than the dimensions of the instrument to allow room for cushioning The shipping carton should have a test strength of at least 2775 pounds 2 Surround the instrument with polyethylene sheeting to protect the finish 3 Cushion the instrument on all sides by tightly packing dunnage or urethane foam between the carton and the instrument Allow three inches on all sides for cushioning 4 Sealthe carton with shipping tape or an industrial stapler VM700T Video Measurement Set Service Manual 6 5 Maintenance Removal and Replacement Instructions 6 6 A A Locating the Major Standard Assemblies WARNING This instrument contains hazardous voltages Before removing covers or performing disassembly reassembly procedures always shut off instrument power at the rear panel switch and disconnect the power cord from electrical mains Failure to do this may result in dangerous electrical shock CAUTION To prevent static discharge damage observe the precautions listed in Preventing Electro Static Damage on page 6 2 This section includes removal and replacement procedures for the following a
372. to the phase comparator Divide by 2 divide by 2 counter divides the 8Fsc VCO output frequency to four times the Frequency Divider color sub carrier frequency 4Fsc and ensures a 50 duty cycle output Frame Decoder The frame decoder examines the composite sync signal from the sync stripper to determine the location of vertical sync The odd field detection modes output a pulse on each odd numbered field The all field detection mode outputs a pulse on every field and uses an algorithm that can detect rudimentary vertical sync information produced by VCRs Frame Rate Synthesizer frame rate synthesizer generates a frame rate frequency output that is used in the synthesized frame mode The frame rate synthesizer does not operate in 20 25 MHz sampling mode Stripped Sync Processing stripped sync logic not shown in the block diagram removes noise from the sync stripper s composite sync output In sound in sync SIS mode the SIS pulses are removed by combining composite sync with the sync stripper s horizontal sync output Impulse noise such as VCR head switches is removed by gating composite sync with a 2 microsecond window pulse centered on the leading edge of sync VM700T Video Measurement Set Service Manual 3 9 Theory of Operation Output Generator The output generator provides sampling line and frame strobes to the analog to digital converter ADC board Sampling strobe output A multiplexer selects either
373. tput one of the following signal sources SDI channel A input SDI channel B input currently selected SDI input channel indicated by front panel LED or none no output You select the signal source in the Source Selection Digital configuration file NOTE You may not be able to use the SDI Output signal effectively as a signal repeater when it is set to output the signal on the SDI channel A input The output of the SDI channel A signal can be interrupted when you access one of the following applications SDI Eye Diagram SDI Jitter and SDI Wander The AES EBU Digital Audio input is used to measure external digital audio signals This BNC input is internally terminated in 75 Q The LTC Time Code input is a standard Longitudinal Time Code interface input used for time stamping measurement log reports VM700T Video Measurement Set Service Manual Operating Information Option 1S rear panel Fan exhaust 996999099 Power Fuse ON OFF Line voltage VGA Parallel Alarm RS 232 connector switch selector output printer port connector ports Figure 2 16 VM700T rear panel with Option 1S installed Figure 2 17 Option 1S rear panel VM700T Video Measurement Set Service Manual 2 23 Operating Information 2 24 VM700T Video Measurement Set Service Manual E Theory of Operation This section describes the electrical operatio
374. treet Melrose MA 02176 FAX 781 665 0780 TestEquipmentDepot com Audio Option Verification Procedure Table 4 2 Test equipment required for verification procedures Minimum specification Example Equipment Sine wave generator Adapter cable three banana plug to one male XLR 2 re quired Female XLR to male mini XLR adapter cable 2 required Dual female XLR to single male XLR connector Dual male XLR to single female XLR connector mates with 2 female XLR to male mini XLR adapter cables Dual female XLR to DB 37 female adapter cable Frequency accuracy 0 0196 level flatness 20 Hz to 20 kHz Required for all Option 40 and Option 41 verification proce 0 05 dB level accuracy 20 Hz dures to 20 kHz 0 2 dB residual distortion 0 001096 100 dB XLR connectors must be wired to current AES recommenda tions pin 1 ground pin 2 hot pin 3 cold Supplied with VM700T Option 40 XLR connectors must be wired to current AES recommenda tions pin 1 ground pin 2 hot pin 3 cold See Figure 2 12 on page 2 19 for XLR connector pin locations XLR connectors must be wired to current AES recommenda tions pin 1 ground pin 2 hot 4 pin 3 cold XLR connectors must be wired to current AES recommenda tions pin 1 ground pin 2 hot pin 3 cold See Figure 2 14 on page 2 20 for pin outs of the VM700T female DB 37 connec tor Connects sine wave generator to adapter cable suppl
375. u can also create edit rename print and delete functions with selections available in the Configu ration menu For a full description of the Configure button and the menus accessed refer to the VM700T Option 01 NTSC and Option 11 PAL User Manual Function Button The Function button accesses user created functions and the selection choices for running them For a full description of creating and editing functions refer to the VM700T RS 232 Interface Programmer Manual Copy Button The Copy button sends a copy of the display in user select able 24 pin Epson or PostScript format to the measurement set print spooler to queue for printing The LED in the Copy button flashes as long as the copy remains in the spooler To delete the copy from the spooler press the Configure button and select the Cancel Copy soft key This soft key only appears when a copy is pending in the spooler To print the spooled copy a suitable printer must be attached to one of the measurement set serial ports or to the parallel printer port You also have to set the Communications configuration file parameters to those needed for the attached printer The action of the control knob depends on its assignment for the current mode of operation For example in Waveform mode rotating the control knob affects horizontal or vertical movement of the display or horizontal or vertical expansion of the display depending on the selections of the Move Expand button a
376. uch the Volt Cursor 2 soft key and then use the front panel knob to position the cursor to the bottom of the sine wave 11 Check that the waveform amplitude readout V1 V2 is 520 mV to 721 mV 65 to 90 VM700T Video Measurement Set Service Manual 4 29 SDI Option 1S Verification Procedure Jitter Application The following Jitter application checks verify the frequency response of the Timing Jitter and Alignment Jitter measurements They also verify the Jitter Waveform and Jitter Spectrum displays including the 10 Hz and 1 kHz filters in both Line and Frame modes NOTE In the following steps you will check the readout of the Jitter timing p p and Jitter Alignment p p measurements Use the value which appears most frequently If two values appear with equal frequency use the larger value If you are using a Tektronix TG2000 Signal Generation Platform with a module you must use Output 2 on the 1 to perform this check l Perform the following steps to check the Jitter application at 270 Mb and 50 Hz a 4 30 Connect a 270 Mb 525 line 10046 color bars signal to the SDI Ch A input Terminate the SDI Ch A input loopthrough using a 75 high frequency terminator Adjust the digital television signal generator for a jitter frequency of 50 Hz and a jitter amplitude of 2 ns on the signal output Press the VM700T front panel Measure button and then touch the SDI Jitter soft key Press the VM7
377. ue Display Abort Auto Reprint Menu Select All A Un Sel All C 1 Done Selecting Display Next Menu Page Arrows Previous Menu Page Move Expand Press Any Key to Continue Figure 6 38 Front Panel diagnostic selection buttons Backdoor Boot Modes The other choice in the diagnostic help menu provides a list of the special power up modes that are accessible through pressing and holding certain of the front panel buttons at power on These are referred to as the backdoor boot modes The choices are shown in Figure 6 39 Bypassing the Power Up Diagnostics The factory Quick Start default bypasses the power up diagnostics to shorten the power up sequence but it also prevents the VM700T from performing self tests at power up If the startup diagnostics have been reconfigured to run at power up they can be bypassed from the front panel at power on To bypass all power up diagnostics both low level and high level when the VM700T is not configured for Quick Start press and hold the Waveform button when you power on the VM700T Release the button after the VM700T beeps twice in about 10 seconds VM700T Video Measurement Set Service Manual Troubleshooting Procedures The VM700T displays the message Startup in Quick Start Mode Recognized Another message indicating all the diagnostics are being bypassed is then displayed and th
378. uracy 0 3 dB 0 6 dB 5 ns 10 ns Absolute mode accuracy 50 ns 50 ns 50 ns Absolute mode accuracy RD 10 ns 225 ns 20 5 VM700T Video Measurement Set Service Manual Specification Table 1 26 Incidental Carrier Phase Modulation Accuracy 1 0 Measurement ICPM requires zero Carrier Pulse and the quadrature output of the demodulator on Channel C Table 1 27 Jitter Measurement Absolute mode accuracy Jitter 2 Field 10 ns Jitter Long Time 10 ns Table 1 28 K Factor Measurement Absolute mode accuracy 2T Pulse K Factor 0 to 10 Kf 0 3 Kpg 10 to 5 Kpg 0 3 Pulse to Bar Ratio 10 to 125 0 7 Pulse Half Amplitude Duration HAD 100 ns to 500 ns 5 ns Table 1 29 Level Meter Measurement Range Accuracy Level Meter 0to 1 4 V 3 5 mV Table 1 30 Line Frequency Accuracy 0 1 0 1 Measurement Line Frequency Field Frequency Table 1 31 Luminance Nonlinearity Measurement Absolute mode accuracy Relative mode accuracy Luminance NonLinearity 0 to 100 0 2 VM700T Video Measurement Set Service Manual 1 15 Specification Table 1 32 MultiBurst Measurement Relative mode accuracy MultiBurst Flag Amplitude NA Packets 1 5 0 5 1 0 2 0 4 0 4 8 MHz 0 03 dB Packet 6 5 8 MHz 0 06 dB Table 1 33 Noise Spectrum Measurement Absolute mode accuracy Unweighted Signal to Noise 20 dB to 80 dB 0 4 dB 20 dB to 60 dB MHz Low Pass 1
379. urate frequency generator or a digital counter to set the frequency The phase measurement requires that both channels have the same signal applied Specifications Checked This procedure checks the following parameters Frequency accuracy 1 Hz or 0 01 1 digit whichever is worse for inputs of 60 dBu and greater in the frequency range of 20 Hz to 20 kHz Channel phase difference 1 for inputs of 40 Hz to 20 kHz 2 for inputs of 20 Hz to 40 Hz at levels of 40 dBu and greater Option 41 Frequency 1 As in Figure 4 9 connect the sine wave generator output to the Audio Accuracy and Channel board Phase 2 Set the sine wave generator for a frequency and amplitude in the specified frequency and amplitude range of the Audio option 20 Hz to 20 kHz amplitude of 60 dBu or greater NOTE Use a test signal level of at least 60 dBu and test at least 10 frequencies over the entire range Tested frequencies should include the specification limits 20 Hz 20 kHz and the 40 Hz breakpoint Example frequencies to test might also include the following 100 Hz 200 Hz 1 kHz 2 kHz 10 kHz 3 Check that the measured frequency is accurate to the limits shown in Table 4 5 for the applied test signal frequency and level and that the phase difference between channels meets the phase difference specification VM700T Video Measurement Set Service Manual 4 23 Audio Option 41 Triple Input Verification Pro
380. ure 6 18 d Remove the wire connecting A4 J915 to A1 J922 at the J922 end only e Remove the wire connecting A4 J418 to A1 J923 at the J923 end only f Remove the cable from its connector at J2 on the Acquisition Memory board A18 g Remove the five board retaining screws h Carefully lift the board from the VM700T chassis and set it aside 2 Perform the following steps to replace the Filter Switch board a Ifthe board has an insulator sheet hold the it against the board to prevent folding and place the board in the chassis and onto the bulkhead standoffs be sure the cable extends out the side of the chassis b Install the five board retaining screws c Install the cable on its connector at J2 on the Acquisition Memory board d Install the power bus cable on its five connectors VM700T Video Measurement Set Service Manual Maintenance J922 J923 J915 M J2 on the A18 Acquisition board J418 Power bus cable VM700T top view Figure 6 18 Removing the Filter Switch board e Replace the wire connecting A4 J915 to Al 1922 f Replace the wire connecting A4 J418 to Al J923 Install the card cage retainer refer to step 4 on page 6 17 h Install the top and right side cover panels refer to Cover Panel Removal and Replacement on page 6 8 VM700T Video Measurement Set Service Manual 6 31 Mainte
381. urn Loss 75 Greater than 46 dB from 0 to 5 MHz Channels A B and C are loop through terminated in 75 in use or not power on or off Input Signal Range 3 6 dB with respect to 1 Vp p nominal video 1 41 Vp p to 0 5 Vp p terminated 75 VM700T Video Measurement Set Service Manual 1 1 Specification Table 1 1 Input characteristics cont Characteristic Clamp Hum Rejection Fast Slow External Sync Crosstalk Between Channels Residual Noise Level 0 to 5 MHz Table 1 2 Digitizer Characteristic Distortions 2nd Harmonic Noise Anti aliasing filter attenuation At 7 16 MHz NTSC At 8 86 MHz PAL 1 2 Performance requirement Supplemental information Independently programmable on each channel as follows 1 Timing with respect to sync 2 Clamp pulse width 3 Clamp reference level 4 Clamp time constant Greater than 24 dB Less than 1 dB Provided through a rear panel input Greater than 70 dB isolation between channels Measured at Fs between A B C and EXT SYNC Better than 80 dB with respect to 0 714 Vp active video Performance requirement Supplemental information 70 dB or less with 2 5 MHz 1 dBfs signal 60 typical with 5 MHz 50 dBfs input 35 dB or greater 40 dB or greater VM700T Video Measurement Set Service Manual Specification Table 1 3 Synchronization Characteristic Performance requirement Supplemental informati
382. us Range 2 seconds VM700T Video Measurement Set Service Manual 1 41 Specification Table 1 104 SDI Ch A Input Characteristic Electrical Characteristics Input type Return Loss Power On Power Off Insertion Loss Power On Power Off Signal Characteristics Amplitude Range Frequency Range 143 Mb s 270 Mb s 360 Mb s Jitter Maximum for No Bit Errors 143 Mb s 270 Mb s 360 Mb s Cable Length Maximum for No Bit Errors 1 42 Performance requirement BNC passive loopthrough 75 2 compensated gt 25 dB 1 MHz to 360 MHz gt 15 dB 1 MHz to 360 MHz 0 3 dB 1 MHz to 360 MHz 1 0 dB 1 MHz to 360 MHz 800 mV 415976 25 20 ppm 20 ppm 20 ppm Equivalent to 200 meters of Belden 8281 cable Supplemental information Channel on or off 2 ns pk to pk for frequencies of 160 kHz and above Max jitter ns 320 jitter frequency KHz for frequencies below 160 kHz 1 ns pk to pk for frequencies of 160 kHz and above Max jitter ns 160 jitter frequency KHz for frequencies below 160 kHz 0 8 ns pk to pk for frequencies of 160 kHz and above Max jitter ns 130 jitter frequency KHz for frequencies below 160 kHz Equivalent to 250 meters of Belden 8281 cable typical VM700T Video Measurement Set Service Manual Specification Table 1 105 SDI Ch B Input Characteristic Electrical Characteristics Input type Return Loss Power On Power Off Signal Characteristics Amplitude R
383. used R 1 Unused FG VM700T DTE to terminal with 9 pin DTE VM700T DTE to terminal with 25 pin 1 Both ends of a DTE to DTE cable are usually female DB 25 connectors VM700T Video Measurement Set Service Manual 6 89 Troubleshooting Procedures Troubleshooting the Power Supply and CRT Display 6 90 A Power Supply This section contains information on how to troubleshoot the power supply module and the CRT display WARNING High voltages present inside the VM700T chassis can cause serious injury All service procedures that require removing instrument covers should be done only by a qualified service person The VM700T power supply is a high efficiency switching supply Field repairs to a VM700T with a power supply problem are done by board exchange Refer to Exchanging VM700T Modules on page 6 3 for more information Front Panel Check Check the LED indicators over the front panel STBY ON switch see Figure 6 60 One red LED is an over temperature warning and the other is a power supply failure indicator If the green Power indicator is on primary power is applied the line fuse is good and the housekeeping voltage supply is operating If no indicators come on either the primary power circuitry has failed or the master ON OFF switch is OFF Check the line fuse and the master ON OFF switch to make sure it is on Also make sure the Line Voltage Selector switch is set to the correct supply voltage If the Line
384. ustment value limits Measurement New data value limits Jitter scale factors Timing 0 650 to 0 800 Align 0 700 to 0 860 Frame 36 000 to 48 000 Line 72 000 to 97 000 Jitter offsets Timing 0 040 to 0 120 Align 0 020 to 0 080 Frame 84 000 to 152 000 Line 84 000 to 152 000 VM700T Video Measurement Set Service Manual 5 25 Adjustment Procedure CAUTION The following Cable Meter adjustment step requires three signals to N complete a 525 line 143 MHz NTC7 combination signal a 525 line 270 Mb 100 color bars signal and any 525 line 360 Mb television signal Do not perform this adjustment unless you have all three signals or you will misadjust the instrument 3 Perform the following steps to adjust the Cable Meter a Touch the Cable soft key NOTE Performing the cable meter adjustment requires two cable lengths 3 meters and 100 meters If you are using a cable clone to simulate 100 meters use 3 meters of cable with the cable clone as shown in Figure 5 11 b If you are using a cable clone for this adjustment connect a 525 line 143 Mb NTC7 combination signal from the digital television signal generator to the cable clone input Connect the cable clone output to the SDI Ch A input Be sure the SDI Ch A loopthrough is terminated using a 75 Q high frequency terminator c Ifyou are using 100 m of cable for this adjustment connect a 525 line 143 Mb NTC7 combination signal from the digital television sign
385. ut Touch the Rescale soft key and then touch the Cursors Units soft key Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 15 kHz as read in the readout Check that the Spectrum Cursor 1 amplitude readout is 2 4 to 8 4 dB Press the VM700T front panel Menu button Select Rate Line using the Rate soft key Touch the Cursors Units soft key Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 15 kHz as read in the readout Check that the Spectrum Cursor 1 amplitude readout is 2 4 to 8 4 dB Check that the Timing p p readout is 1600 to 2600 ps Check that the Alignment p p readout is 1600 to 2600 ps VM700T Video Measurement Set Service Manual 4 31 SDI Option 1S Verification Procedure 4 32 4 Perform the following steps to check the Jitter application at 270 Mb and 0 5 MHz a d e Adjust the digital television signal generator for a jitter frequency of 0 5 MHz and a jitter amplitude of 1 ns on the signal output Touch the Spectrum Cursor 1 soft key and then use the front panel knob to position the cursor to 0 5 MHz as read in the readout Check that the Spectrum Cursor 1 amplitude readout is 8 4 to 14 4 dB Check that the Timing p p readout is 800 to 1400 ps Check that the Alignment p p readout is 800 to 1400 ps 5 Perform the following steps to check the Jitter application at 270 Mb and 5 MHz a
386. ve connectors f Connect the interconnection ribbon cable from the Acquisition Memory board to J8 of the Genlock board Install the card cage retainer refer to step 4 on page 6 17 h Install the top and right side cover panels refer to Cover Panel Removal and Replacement on page 6 8 VM700T Video Measurement Set Service Manual 6 27 Maintenance ADC Board Removal and 6 28 Replacement Removing and replacing the ADC board A3 consists of removing the instru ment top and right side covers disconnecting three flat cable assemblies disconnecting a shielded cable and removing the screws holding the board in position With the screws removed the board may be lifted from the VM700T chassis and set aside Required Tools Use the following tools to remove the ADC circuit board W Pozidriv screwdriver 1X 2X Procedure Use the following procedure to remove and replace the ADC board l Perform the following steps to remove the ADC board a Remove the top and right side cover panels refer to Cover Panel Removal and Replacement on page 6 8 Remove the card cage retainer refer to step 1 on page 6 16 Disconnect the flat 10 conductor cable between J111 and J6 on the Genlock board Disconnect the shielded cable between J765 located on the ADC Filter board and J6 on the Analog Input board see Figure 6 17 At the Acquisition Memory board right side of the instrument disconnect the cable at J6 Di
387. vice Manual Operating Information m Signal Inputs These are the connections for Channel A B and C signal inputs to the measurement set External Sync This input allows you to connect the measurement set to an external sync source m RS 232 Ports These ports are the serial interface from the measurement set to a printer for printing displayed data screens and logging information The RS 232 ports also enables you to access the measurement set remotely using a terminal or a PC Refer to the VM700T RS 232 Interface Programmer Manual for information on configuring the measurement set for remote access and the remote control commands properly grounded to prevent applying a floating voltage to the measurement set CAUTION Peripheral equipment operating on ac mains voltages must be internal circuitry that can cause damage Parallel Printer Port You can use this port to connect the measurement set to a Centronics compatible parallel printer Uploading firmware upgrades is also done through the printer port The firmware and uploading program are distributed on disk and uploaded from a personal computer through the parallel printer port You will need a computer to computer data cable for example and XT compatible LapLink cable to make the connection for uploading VGA Output You can view the measurement set display on a standard VGA monitor connected to the VGA output connector 2 The signal inputs and the ext
388. wing steps to remove the Acquisition Memory board a Remove the right side cover panel refer to Cover Panel Removal and Replacement on page 6 8 b Remove the card cage retainer refer to step 1 on page 6 16 c The Acquisition Memory board occupies the top slot in the right side card cage see Figure 6 10 To remove this board you must first disconnect the ribbon cables shown on the right side of Figure 6 11 d Spread the cable ejector tabs to disconnect each cable from the circuit board e Unplug the circuit board using the ejector tab to release the board from the main interconnection board When the circuit board is loose slide it out of the card cage 2 Perform the following steps to replace the Acquisition Memory board a Guide the board onto the top right side card cage track and slide it into the card cage connector b Align the circuit board connector pins with the main interconnection board connector and press firmly to seat the connector c Reinstall each of the cables to the Acquisition board ensuring that they are firmly seated in the board connectors see Figure 6 11 d Install the card cage retainer refer to step 4 on page 6 17 e Install the cover panel refer to Cover Panel Removal and Replacement on page 6 8 VM700T Video Measurement Set Service Manual Maintenance J2 on the A18 Acquisition board J4 on the A18 Acquisition
389. wo DB9 RS 232C DTE serial ports on its rear panel see Figure 6 59 These serial ports can be used to send graphics and reports to a printer for remote operation via a modem or for viewing diagnostics by direct serial connection to an RS 232C device such as a terminal Both serial port 9 pin male D connectors are located on the A20 CPU I O board and are accessible from the rear panel of the instrument as shown in Figure 6 59 Fan exhaust 0000 00 O00 Parallel Alarm RS 232 printer port connector ports Figure 6 59 VM700T rear panel The Communications Setup file located in the Configure Files directory contains the parameter settings for the serial ports Typical Communications Setup choices for VM700T to PC communications are shown in Table 6 6 Table 6 6 Typical communication setup parameters Seccion Parameter lomane Reset raran _ xowxort Carer Deter ho Selection Parameter None Disabled Disabled Protocol Baud Rate Flow Control Character Size VM700T Video Measurement Set Service Manual 6 87 Troubleshooting Procedures 6 88 VM700T RS 232 Connector Pin Outs The two RS 232C DTE ports of the VM700T are used to output graphics and reports to a printer as well as for remote operation via a modem or direct serial connection Both connectors are located on the CPU I O board and are

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