Chapter 9
449
IF Section
Log Amplifier (P/O A4 Assembly)
2. If an FM signal cannot be demodulated, perform the Demodulator
Adjustment procedure. If the output of A4C707 cannot be adjusted
as described in the Demodulator Adjustment procedure,
troubleshoot the FM Demodulator or Audio MUX circuits on A4.
4.8 kHz IF Filters
Refer to function block N of A4 Log Amplifier Schematic Diagram (sheet
3 of 4) in the 8560 E-Series Spectrum Analyzer Component Level
Information.
Problems with the 4.8 kHz filters can result in spurious signals
appearing 2.88 kHz to 3.52 kHz greater than the frequency of the
desired response. Also,
ERR 536 RBW <300
may occur when problems
exist with the 4.8 kHz IF filters.
Measure the passband of the 4.8 kHz IF filters as described in the
following procedure:
1. On the 8564EC or 8565EC spectrum analyzer, press
CAL
,
IF ADJ
OFF
,
SPAN
, and 600
Hz
.
2. Disconnect W27 from A4J3 and inject a 10.7 MHz signal of
−
20 dBm
into A4J3.
3. Fine-tune the frequency of the signal generator to center the signal
on the screen. Set the signal generator to sweep one 2 kHz span
about this center frequency. Press
SGL SWP
on the 8564EC or
8565EC spectrum analyzer.
4. Set another spectrum analyzer, such as the 8566A/B, to 4.8 kHz
center frequency and 2 kHz span.
CAUTION
If a dc block is not used, damage to the 8566A/B results. The 8566A/B
and many other spectrum analyzers have dc-coupled inputs and cannot
tolerate dc voltages on their inputs.
5. Connect the VIDEO OUTPUT (rear panel) of the 8564EC or
8565EC spectrum analyzer through a 20 dB attenuator and dc
block to the input of the 8566A/B. Set the sweep time of the 8566A/B
to 10 seconds.
6. Set the 8566A/B to single trigger and press TRACE A
CLEAR-WRITE
.
Trigger a sweep of the 8566A/B and the signal generator
simultaneously. The 8566A/B shows the passband of the 4.8 kHz IF
filters. The 3 dB bandwidth of the filters should be 1.2 kHz. The
passband of the filters should be flat within 2 dB over 800 Hz.
7. Reconnect W27 (coax 3) to A4J3.
Summary of Contents for 8564EC
Page 17: ...25 1 General Information ...
Page 37: ...47 2 Adjustment Diagnostic Software ...
Page 77: ...89 3 Manual Adjustment Procedures ...
Page 129: ...161 3a Manual Adjustment Procedures 3335A Source not Available ...
Page 142: ...175 4 Assembly Replacement ...
Page 194: ...Chapter 4 257 Assembly Replacement Procedure 13 A21 OCXO Figure 4 34 A21 OCXO Mounting Screws ...
Page 196: ...259 5 Replaceable Parts ...
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Page 224: ...303 6 Major Assembly and Cable Locations ...
Page 234: ...315 7 General Troubleshooting ...
Page 238: ...Chapter 7 319 General Troubleshooting Introduction Figure 7 2 Ribbon Cable Connections 1 of 3 ...
Page 239: ...320 Chapter7 General Troubleshooting Introduction Figure 7 3 Ribbon Cable Connections 2 of 3 ...
Page 242: ...Chapter 7 323 General Troubleshooting Introduction Figure 7 5 Service Cal Data Menu ...
Page 271: ...352 Chapter7 General Troubleshooting Block Diagram Description Figure 7 6 Functional Sections ...
Page 283: ...364 Chapter7 General Troubleshooting Block Diagram Description ...
Page 284: ......
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Page 286: ......
Page 287: ...377 8 ADC Interface Section ...
Page 291: ...Chapter 8 381 ADC Interface Section Introduction Figure 8 2 A3 Test Connector Pin Locations ...
Page 321: ......
Page 322: ...427 9 IF Section ...
Page 356: ...Chapter 9 461 IF Section A5 IF Assembly Figure 9 13 Detailed IF Adjust Signature 5 ...
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Page 379: ...487 10 Controller Section ...
Page 394: ...521 11 Synthesizer Section ...
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Page 454: ...593 12 RF Section ...
Page 489: ...628 Chapter12 RF Section A15 RF Assembly Figure 12 10 10 MHz TTL Reference at U304 Pin 13 ...
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Page 492: ...633 13 Display Power Supply Section ...
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Page 505: ...671 14 Component Level Information Packets ...
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