Self Tests Do Not Run Or Self Tests Run Slowly - Keysight N5171B EXG Service Manual

Troubleshooting
Running Self Test
7. Set up the signal generator:
8. Accounting for the attenuated output signal from the generator. The
9. Repeat step 6 through 8, but change the spectrum analyzer's and the
Depending on the interaction of the ALC circuit, the measured output
power may increase as the frequencies increase.
Frequencies above 2 GHz are controlled by the High Band ALC detector
and will not be visible when making measurements in the Low Band ALC
detector range.

Self Tests Do Not Run or Self Tests Run Slowly

If self tests will not run or run slowly, the most likely cause is a faulty A1 Power
Supply or A5 CPU assembly. The A5 CPU assembly relies on correct power
supply voltages. If the A1 Power Supply is faulty, it could cause a false A5 CPU
assembly error.
1. Troubleshoot the A1 Power Supply. Refer to
36
a. Press Preset.
b. Press Freq. Set the frequency to 100 MHz.
c. Press RF On/Off to On.
d. Press AMPTD > +10 dBm.
e. Press AMPTD > ALC On.
spectrum analyzer should be displaying a CW signal with an amplitude of
approximately what the signal generator is set minus the in-line
attenuation. The measured value could be 1 or slightly more dB different.
a. If the signal generator's output level is significantly different than
the typical 2 or 3 dB, replace the A3 RF Assembly.
b. If the signal generator's output level is as expected, continue to step
9.
signal generator's frequencies to 1 GHz and then 1.5 GHz.
— If the power level is as expected at all test frequencies, replace the
A7 Micro Deck.
— If the power level is NOT as expected at all frequencies, replace the
A3 RF Deck.
Troubleshooting" on page
"A1 Power Supply
45.
Keysight X-Series Signal Generators Service Guide