Keysight N9038A, Руководство по обслуживанию

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186 Keysight N9038A MXE Service Guide
RF Preselector Section
RF Preselector Section Troubleshooting
12. Turn the instrument Preamp on by pressing AMPTD , More , Internal
Preamp , Low Band .
13. Verify that the signal level on the spectrum analyzer increases by at least
20 dB from where it was, as shown in Figure 5-13 .
If the signal level is incorrect the most likely cause of the problem is the
A21 RF Preselector Input assembly itself. However, if there is no RF
Preselector alignment data the signal level when the preamplifier is turned
on could also be low. Before replacing the A21 RF Preselector Input
assembly for a low preamplifier level try running the alignment routine by
pressing System , Alignments , More , RF Preselector , Align Now , 20 Hz to
30 MHz . Once the alignment is completed check the level again.
Figure 5-13 A21 RF Preselector Input Assembly - Conducted Band Preamp
14. Turn the instrument Preamp off by pressing AMPTD , More , Internal
Preamp , Off .
Output Signal Routing Verification - Radiated Band
If there is a particular frequency of interest use that instead of the 100 MHz used in this example