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Message ID: 3530     Entry time: Tue Sep 7 08:56:00 2010
Author: Alberto 
Type: Update 
Category: Electronics 
Subject: Frequency Generation Box Assembly - Phase Noise Measurements 

Here are the results of my phase noise measurements on the 7 outputs of the Frequency Generation Box. (BIN=95L applied by DTT). See attached pdf for a higher definition picture.

2010-09-03_FreqBoxPhaseNoise_AllOutputsComparison_smooth.png

The plot shows that the phase noise of the 11 MHz outputs (Source, EOM modulation signal, Demodulation signal) is as low as that of the Marconi. The Marconi is limiting my measurement's resolution.

The mode cleaner signal's oscillator (29.5 MHz output, blue trace) is higher than the 11MHz above 1KHz.

The 55MHz signals have all the same phase noise (traces overlapped), and that is higher than the 11 MHz ones from about 100Hz up. i don't know what's going on.

I need to use the spare 11MHz Wenzel crsytal to have a better reference source for the measurement.

Attachment 2: 2010-09-03_FreqBoxPhaseNoise_AllOutputsComparison_smooth.pdf  261 kB  | Hide | Hide all
2010-09-03_FreqBoxPhaseNoise_AllOutputsComparison_smooth.pdf
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