Keysight NFA Series Noise Figure Analyzers Service Guide 147
RF Section Troubleshooting (N8973B, 74B, 75B Analyzers)
Troubleshooting
If the Reference assembly calibrator is functioning properly the 50 MHz
calibrator signal will measure 50 MHz at −25 dBm ± 3 dB. See Figure 4-6. If
this level is incorrect, the Reference assembly is most likely defective.
Reconnect W19 at A9 Input Attenuator A.
Figure 4-6 50 MHz Calibrator Signal