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Entry  Wed Oct 15 22:07:52 2008, pete, Configuration, PSL, FSS ref phase measurements phasedelay.png
    Reply  Thu Oct 16 09:47:49 2008, Yoichi, Configuration, PSL, FSS ref phase measurements 
Message ID: 1052     Entry time: Thu Oct 16 09:47:49 2008     In reply to: 1050
Author: Yoichi 
Type: Configuration 
Category: PSL 
Subject: FSS ref phase measurements 

I fit the bottom (quadratic) portion of this curve, and found an optimum delay of 25.8 ns, which can be implemented as 25.81 ns on the phase shift box (25 + 1/2 + 1/4 + 1/16).

The gain of the loop is sinusoidally dependent on the phase delay. So the fit will be better with a function like this: 1/(1+G*sin(dphi + const)).
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