Agilent Technologies PSG Series Service Manual page 55

Troubleshooting
Troubleshooting Assembly Level Problems
1204 RF Path
This test checks for a dc voltage on the A10 ALC from the A23 Low Band Coupler/Detector and
A24 High Band Coupler and A25 High Band Detector.
1. Connect a spectrum analyzer to the RF output of the signal generator. Turn the RF power on and verify
the presence of an RF signal on the output. If no RF signal is present, troubleshoot the RF problem using
the RF Path procedure.
2. If an RF signal is present on the RF output, set the signal generator to 4 GHz and 0 dBm. Measure the dc
voltage on the cable going to J3 of the A10 ALC. The signal should be > -600 mV. If the signal at J3 is good,
go to step e.
3. If no dc signal is present on the cable to J3, check the output at the high band detector. If the signal is good
at the detector replace the cable.
4. If no signal is present at the output of the high band detector, replace the high band detector.
5. If the signal is good at J3, set the signal generator's frequency to <1 GHz and power to 0 dBm. Measure
the dc voltage on the cable going to J5 on the A10 ALC.
6. If dc voltage in step e is -5.25 Vdc, replace the A10 ALC.
7. If dc voltage is present, check for dc voltage on the output of the low band detector. If a dc voltage is
present, replace the cable.
8. If no dc voltage is present, replace the low band detector.
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