370
Chapter 7
ADC/Interface Section
A3 Assembly Video Circuits
13.Press
CAL
and
IF ADJ ON OFF
until OFF is underlined. Monitor
A3TP9 with an oscilloscope. If the voltage is not approxi1
Vdc, troubleshoot the Log Amplifier on A4. (Refer to the IF
troubleshooting procedure in Chapter 8.)
14.To confirm proper video input to the video circuit, set the HP
8560E/EC to Log 10 dB per division and change the reference level
in 10 dB steps from
−
10 dBm to +30 dBm. At each 10 dB step, the
input voltage should change 100 mV. The input level should be +0.6
Vdc for a +30 dBm reference level.
NOTE
The on-screen amplitude level will probably not change as expected,
since the video circuitry is assumed to be faulty.
15.Monitor A3TP14 while stepping the reference level from
−
10 dBm to
+30 dBm. If the voltage does not step approximately 100 mV per 10
dB step, refer to "Video MUX" in this chapter.
16.If the Video MUX is working properly, monitor A3TP15 with the
oscilloscope and step the reference level from
−
10 dBm to +30 dBm.
If the voltage does not change 100 mV per 10 dB step, refer to "Video
Filter" in this chapter.
17.If the voltage at A3TP15 is correct, move the oscilloscope probe to
A3TP17 and step the reference level between
−
10 dBm and +30
dBm. If the voltage does not change 100 mV per 10 dB step, refer to
"Video Filter Buffer Amplifier" in this chapter.
18.If the voltage at A3TP17 is correct, move the oscilloscope probe to
A3TP6. Set the following controls to keep the ADC MUX set to the
MOD_VIDEO input during the sweep.
SWEEP TIME ................................................................... 50 s
DETECTOR MODE ................................................ SAMPLE
19.Step the reference level from
−
10 dBm to +30 dBm while monitoring
the voltage change on the oscilloscope. If the voltage does not change
100 mV per 10 dB step, refer to "ADC MUX" in this chapter.
20.If the voltage at A3TP6 is correct, move the oscilloscope probe to
A3TP8 and step the reference level between
−
10 dBm and +30 dBm.
If the voltage at A3TP8 is not the same as that at A3TP6, replace
A3U110.
21.If the voltage at A3TP8 and A3TP6 are equal, move the oscilloscope
probe to A3TP7.
22.Change the reference level from
−
10 dBm to 0 dBm. The voltage
change on A3TP7 should be between 630 mV and 770 mV. If the
voltage change is outside of these limits, refer to "Variable Gain
Amplifier (VGA)" in this chapter. The gain of the VGA should be 7
±
10%.
Summary of Contents for 8560E
Page 17: ...16 Contents ...
Page 24: ...23 1 General Information ...
Page 49: ...48 Chapter1 General Information Sales and Service Offices ...
Page 50: ...49 2 Adjustment Procedures ...
Page 132: ...131 2a Adjustment Procedures HP 3335A Source not Available ...
Page 146: ...145 3 Assembly Replacement ...
Page 224: ...223 4 Replaceable Parts ...
Page 251: ...250 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 253: ...252 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 255: ...254 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 257: ...256 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 259: ...258 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 261: ...260 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 263: ...262 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 265: ...264 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 267: ...266 Chapter4 Replaceable Parts Firmware Dependent Part Numbers ...
Page 268: ...267 5 Major Assembly and Cable Locations ...
Page 279: ...278 Chapter5 Major Assembly and Cable Locations Introduction Figure 5 9 Front End ...
Page 281: ...280 Chapter5 Major Assembly and Cable Locations Introduction ...
Page 282: ...281 6 General Troubleshooting ...
Page 285: ...284 Chapter6 General Troubleshooting Introduction Figure 6 1 Assembly Test Points ...
Page 286: ...Chapter 6 285 General Troubleshooting Introduction Figure 6 2 Ribbon Cable Connections 1 of 3 ...
Page 287: ...286 Chapter6 General Troubleshooting Introduction Figure 6 3 Ribbon Cable Connections 2 of 3 ...
Page 290: ...Chapter 6 289 General Troubleshooting Introduction Figure 6 5 Service Cal Data Menu ...
Page 331: ...330 Chapter6 General Troubleshooting Block Diagram Description Figure 6 6 Functional Sections ...
Page 343: ...342 Chapter6 General Troubleshooting Block Diagram Description ...
Page 345: ...344 Chapter6 General Troubleshooting Block Diagram Description ...
Page 347: ...346 Chapter6 General Troubleshooting Block Diagram Description ...
Page 349: ...348 Chapter6 General Troubleshooting Block Diagram Description ...
Page 351: ...350 Chapter6 General Troubleshooting Block Diagram Description ...
Page 353: ...352 Chapter6 General Troubleshooting Block Diagram Description ...
Page 354: ...353 7 ADC Interface Section ...
Page 406: ...405 8 IF Section ...
Page 436: ...Chapter 8 435 IF Section A5 IF Assembly Figure 8 3 IF Adjust Signature ...
Page 437: ...436 Chapter8 IF Section A5 IF Assembly Figure 8 4 Detailed IF Adjust Signature 1 ...
Page 438: ...Chapter 8 437 IF Section A5 IF Assembly Figure 8 5 Detailed IF Adjust Signature 2 ...
Page 439: ...438 Chapter8 IF Section A5 IF Assembly Figure 8 6 Detailed IF Adjust Signature 3 ...
Page 440: ...Chapter 8 439 IF Section A5 IF Assembly Figure 8 7 Detailed IF Adjust Signature 4 ...
Page 441: ...440 Chapter8 IF Section A5 IF Assembly Figure 8 8 Detailed IF Adjust Signature 5 ...
Page 443: ...442 Chapter8 IF Section A5 IF Assembly Figure 8 9 Noisy Signature ...
Page 444: ...Chapter 8 443 IF Section A5 IF Assembly Figure 8 10 Noise with Correct Shape ...
Page 445: ...444 Chapter8 IF Section A5 IF Assembly Figure 8 11 Region B Amplitude Variation ...
Page 447: ...446 Chapter8 IF Section A5 IF Assembly Figure 8 13 Faulty Crystal Short ...
Page 463: ...462 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 465: ...464 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 467: ...466 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 469: ...468 Chapter8 IF Section Cal Oscillator Assembly P O A4 ...
Page 470: ...469 9 Controller Section ...
Page 486: ...Chapter 9 485 Controller Section Display Problems 8560E Figure 9 10 Delta Y Waveform ...
Page 503: ...502 Chapter9 Controller Section Keyboard Problems ...
Page 505: ...504 Chapter9 Controller Section Keyboard Problems ...
Page 506: ...505 10 Synthesizer Section ...
Page 577: ...576 Chapter10 Synthesizer Section A21 OCXO ...
Page 579: ...578 Chapter10 Synthesizer Section A21 OCXO ...
Page 581: ...580 Chapter10 Synthesizer Section A21 OCXO ...
Page 582: ...581 11 RF Section ...
Page 598: ...Chapter 11 597 RF Section A14 Frequency Control Assembly Figure 11 2 A7 LODA Drive ...
Page 617: ...616 Chapter11 RF Section A10 Tracking Generator Option 002 ...
Page 618: ...617 12 Display Power Supply Section ...
Page 651: ...650 Chapter12 Display Power Supply Section A6 Power Supply Assembly ...
Page 653: ...652 Chapter12 Display Power Supply Section A6 Power Supply Assembly ...
Page 654: ...653 13 Component Level Information Packets ...
Page 660: ...Chapter 13 659 Component Level Information Packets Introduction ...