High Band Preamp (Option P08, P13, P26); High Band Mixing Equations - Keysight n9020a Service Manual

RF Section Troubleshooting
Troubleshooting

High Band Preamp (Option P08, P13, P26)

If any of the preamp options listed above is installed, the High Band preamp
can be verified as follows:
View the 4.8 GHz calibrator signal on screen. Press AMPTD, More, Internal
Preamp, Full Range to activate the preamp. The expected operation is the
signal level will not change more than ± 0.5 dB and the noise floor will increase
due to the fact the input attenuation was automatically increased.
If the amplitude error when switching the preamp on and off is greater than
0.5 dB, assure that any other internal alignment failures are resolved since the
System Gain alignment must run before optimum performance is possible. The
amplitude error could be caused by poor frequency response, and performing
the high band frequency response adjustment (using the calibration software)
will adjust the preamp on, high band path. Assure you have evaluated all
causes including A15 Front End Controller switching problems, before you
replace the Front End assembly.

High Band Mixing Equations

For input signal frequencies from 3.6 GHz to 8.4 GHz and 13.6 GHz to 17 GHz:
RF = LO x N − IF
IF = LO x N − RF
LO x N = IF + RF
where RF is the input signal at the signal analyzer
where N is the harmonic mixing mode:
For input signal frequencies above 8.4 GHz to 13.6 GHz and 17 GHz to
26.5 GHz:
RF = LO x 2 x N − IF
IF = LO x 2 x N − RF
LO x 2 x N = IF + RF
where RF is the input signal at the signal analyzer
where N is the harmonic mixing mode:
N = 1 for 3.5 GHz to 8.4 GHz
N = 2 for 13.5 GHz to 17 GHz
N = 1 for 8.4 GHz to 13.6 GHz
N = 2 for 17 GHz to 26.5 GHz
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