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Entry  Mon May 3 01:16:50 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup pn.png
    Reply  Tue May 4 18:40:27 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup Untitled.pngifrnoise.png
    Reply  Tue May 11 18:58:49 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup Untitled.png
       Reply  Wed May 12 02:21:56 2010, rana, HowTo, Electronics, Marconi phase noise measurement setup pn.png
Message ID: 2879     Entry time: Tue May 4 18:40:27 2010     In reply to: 2869
Author: rana 
Type: HowTo 
Category: Electronics 
Subject: Marconi phase noise measurement setup 

To check the UGF, I increased the gain of the PLL by 10 and looked at how much the error point got suppressed. The green trace apparently has a UGF of ~50 Hz and so the BLUE nominal one has ~5 Hz.

The second attachment shows the noise now corrected for the loop gain. IF the two signal generators are equally noisy, then you can divide the purple spectrum by sqrt(2) to get the noise of a single source.

The .xml file is saved as /users/rana/dtt/MarconiPhaseNoise_100504.xml

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