Specifications
Noise Sidebands Troubleshooting
Agilent Technologies
PSA Series Spectrum Analyzers
Test and Adjustment Software
Noise Sidebands Troubleshooting
Related Adjustments
● None
If the Noise Sidebands test fails, check the results of the DANL TEST. If DANL is out of
spec, there is a good possibility that the high average noise level is causing the noise
sidebands test to indicate a false failure.
Phase Noise is a parameter that describes short term instability of LO tune frequency.
Phase Noise appears as modulation sidebands near the LO. The modulation source is
noise within the LO Phase Lock Loop.
A Noise Sidebands failure would indicate that noise is being injected into the LO Phase
Lock Loop. The assembly most likely to be the source of the failure would be the A18
YTO assembly.
If the noise sideband is relative to a carrier frequency below 3 GHz, suspect the A9 2
nd
LO Assembly. The 2
nd
LO Assembly is turned off in highband (frequencies above 3
GHz), which means it cannot cause a problem in highband.
Failures at the 100 HZ offset are usually caused by 10 MHz Oven Controlled Crystal
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