Signal Level Problem With Input Frequencies > 3.6 Ghz - Keysight N8973B Service Manual

Boot Up and Initialization Troubleshooting
Signal Level Verification
Signal Level Problem with
Input Frequencies > 3.6 GHz
Measure the 4.8 GHz RF calibrator signal level by pressing MODE/MEAS,
Spectrum Analyzer, OK, Input/Output, RF Calibrator, 4.8 GHz. Now press
FREQ, 4.8 GHz, Span, 1 MHz, Peak Search. If the analyzer is functioning
correctly in high band, the 4.8 GHz calibrator level should be −28 dBm ± 2 dB.
See the figure below.
Is the signal level correct?
If yes:
If no:
It is possible that other input frequencies > 3.6 GHz could have an
amplitude problem even though the 4.8 GHz calibrator is within tolerance.
Using the internal RF calibrator provides a quick check of the high band
path.
Keysight NFA Series Noise Figure Analyzers Service Guide
The analyzer high band path is functioning properly at least at 4.8 GHz.
Refer to Chapter 4, "RF Section Troubleshooting (N8973B, 74B, 75B
Analyzers)" in this manual.
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