Keysight Technologies N9030B, Service Manual

Page: 171 / 617

N9030B PXA Signal Analyzer Service Guide 171
RF Section Troubleshooting (RF/Microwave Analyzers)
Troubleshooting
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:
N = 1 for 3.5 GHz to 8.4 GHz
N = 2 for 13.5 GHz to 17 GHz
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 = RF + IF
where RF is the input signal at the signal analyzer
where N is the harmonic mixing mode:
N = 1 for 8.4 GHz to 13.6 GHz
N = 2 for 17 GHz to 26.5 GHz
Low Noise Path (Option LNP)
Allows the Lowband Switch assembly to be bypassed, improving sensitivity in
highband path.
Press
Amplitude , uW Path Control , Low Noise Path Enable key. The Low
Noise Path will be enabled only after the following conditions are met:
1. The start frequency must be 3.6 GHz or greater.
2. The high band preamp (option P08, P18, P26) must be Off.
When Switch 3 changes state, you will hear a click. The amplitude of the
displayed signal should not change.
Microwave Preselector Bypass (Option MPB)
Allows the YTF to be bypassed improving amplitude accuracy.
Assure start frequency is 3.6 GHz or greater. Press
Amplitude , uW Path
Control , uW Preselector Bypass .
When the bypass switches Switch 1 and Switch 2 change state you will hear a
click. Depending on the signal source connected, you may see many “signals”
appear on screen because without preselection, the analyzer will display
images and multiples. The real input signal should not change amplitude when
you switch the uW Preselector Bypass on and off.