HP 8924E, Assembly

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Chapter 2, Troubleshooting
More about Step 4 - Verify Test Set Functioning
N:\mkt\MANUALS\HP8924C\ALR\trouble.fb
Receiver Synthesizer (A28) Unlocked
1. Turn the Test Set off.
2. Remove the rear assemblies cover (two assembly pry tools are removed in the process).
3. Use the pry tools to remove the Receiver Synthesizer assembly.
4. Turn the Test Set on.
5. Verify that a 1 MHz signal of about - 1 dBm is present on pin 3 of J40. This is the
reference signal from the Reference assembly.
6. If the signal is present, replace the Receiver Synthesizer assembly.
If the 1 MHz signal is not present, the Reference (A27) assembly is probably faulty. It
is also possible that an open or shorted trace on the Motherboard assembly (A40)
exists. Check for continuity between J40 pin 3 (under the Receiver Synthesizer) and
J34 pin 2 (under the Reference assembly), and verify that the trace is not shorted to
ground.
Signal Generator Synthesizer (A24) Unlocked
1. Turn the Test Set off.
2. Remove the rear assemblies cover (two assembly pry tools are removed in the process).
3. Use the pry tools to remove the Receiver Synthesizer assembly.
4. Turn the Test Set on.
5. Verify that a 1 MHz signal of
≥ −20
dBm is present on pin 3 of J31. This is the reference
signal from the Reference assembly.
6. If the signal is present, replace the Signal Generator Synthesizer assembly.
If the 1 MHz signal is not present, the Reference (A27) assembly is probably faulty. It
is also possible that an open or shorted trace on the Motherboard assembly (A40)
exists. Check for continuity between J31 pin 3 (under the Signal Generator
Synthesizer) and J34 pin 1 (under the Reference assembly), and verify that the trace is
not shorted to ground.