Keysight E8257D/67D - Page 57

E8257D/67D, E8663D PSG Signal Generators Service Guide
Troubleshooting
Troubleshooting Assembly–Level Problems
1-43
900 Power Supply
• Replace the 10 ALC assembly.
901 Detector Test
1. Using a digital voltmeter, check J3 for approximately –0.29 Vdc:
a. Turn the signal generator’s RF power on.
b. Set the frequency to 10 GHz and the RF power level to +20 dBm, ALC off.
c. Disconnect the cable from J3 of the A10 ALC (W15) and connect the cable to the voltmeter.
• If the signal is not present, refer to highband RF loop troubleshooting.
• If the signal is present, replace the A10 ALC.
902 Detector Level to ALC Ref
1. Using a digital voltmeter, check J5 for –2.3 Vdc:
a. Turn the signal generator’s RF power on.
b. Set the frequency to 1 GHz and the RF power level to +20 dBm, ALC off.
c. Disconnect the cable from J5 of the A10 ALC (W14) and connect the cable to the voltmeter.
• If the signal is not present, refer to lowband RF loop troubleshooting.
2. If the signal is present, check J3 for –0.29 Vdc:
a. On the signal generator, change the frequency to 10 GHz.
b. Disconnect the cable from J3 of the A10 ALC (W15) and connect the cable to the voltmeter.
• If the signal is not present, refer to highband RF loop troubleshooting.
• If the signal is present, replace the A10 ALC.
903 Level Test
1. Using a digital voltmeter, check J3 for –0.29 Vdc:
a. Turn the signal generator’s RF power on.
b. Set the frequency to 10 GHz and the RF power level to +20 dBm.
c. Disconnect the cable from J3 of the A10 ALC (W15) and connect the cable to the voltmeter.
• If the signal is not present, refer to highband RF loop troubleshooting.
• If the signal is present, replace the A10 ALC.
904 Scalar Mod Pulse
• Replace the A10 ALC.
905 ALC Mod Test
• Replace the A10 ALC.
906 Scan Mod Test
• Replace the A10 ALC.
+3.4 Digital Low P121–60, 61, 62, 63, 125, 126, 127, 128 +3.29 +3.5 Main Supply
Supply
Voltage
(Vdc)
Connector Pins Minimum
Value
(Vdc)
Maximum
Value
(Vdc)
Origin