372
Chapter 7
ADC/Interface Section
A3 Assembly Video Circuits
Video MUX
Refer to function block U of A3 Interface Assembly Schematic
Diagram (sheet 5 of 6) in the
HP 8560 E-Series Spectrum Analyzer
Component Level Information
.
1. Press
PRESET
and set the HP 8560E/EC controls as follows:
Center frequency ..................................................... 300 MHz
Span ................................................................................. 0 Hz
2. Press
SGL SWP
,
CAL
, and
IF ADJ OFF
. Connect the CAL OUTPUT to
the INPUT 50
Ω
connector.
3. Check for a TTL high on A3U104 pin 2 and a TTL low on U104 pin
10. Set the spectrum analyzer to 2 dB/div and check for a TTL high
on A3U104 pin 10 and a TTL low on A3U104 pin 2.
4. If the logic levels on A3U104 are incorrect, check the LLOG_STB
signal as follows:
a. Monitor A3U104 pin 9 with an oscilloscope or logic probe. Check
that a 1 microsecond, low-going pulse is present when switching
between 10 dB/div and 2 dB/div.
b. Check the inputs to A3U104 (pins 3 and 11) while switching
between 10 dB/div and 2 dB/div.
c. If the logic signals are incorrect, refer to "Analog Bus Timing" and
"Analog Bus Drivers" in this chapter.
5. Check comparators A3U109A/C for proper outputs. The outputs
should be high when the noninverting input is greater than the
threshold voltage of +1.3 Vdc.
6. If A3U104 and A3U109 are working properly, set the
AMPLITUDE
and
REF LVL
to 0 dBm.
7. Monitor the voltage at A3TP14 while switching the spectrum
analyzer between 10 dB/div and 2 dB/div. The voltage should switch
between 0.8 and 0.4 Vdc.
8. If the voltage at A3TP14 is incorrect, suspect either A3Q220 or
A3Q221.
9. The Video MUX will appear faulty if A3CR109 is shorted or leaky.
Diode A3CR109 clamps the voltage at A3TP14 to
−
0.4 V when in log
expand, with less than 0.8 V at J101. To confirm this failure, lift the
cathode of diode A3CR109 and repeat steps 1 through 7.
10.To return the HP 8560E/EC to automatic sweep, press
SWEEP
,
SWEEPCONT SGL
or press
PRESET
.
Video Filter
Refer to function block V of A3 Interface Assembly Schematic
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 ...