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Entry  Wed Aug 8 20:34:29 2012, Jenne, Update, ASS, Trouble measuring sensing matrix 
    Reply  Wed Aug 8 20:50:39 2012, Koji, Update, ASS, Trouble measuring sensing matrix 
       Reply  Thu Aug 9 00:23:11 2012, Jenne, Update, ASS, Trouble measuring sensing matrix 
          Reply  Thu Aug 9 01:26:03 2012, Koji, Update, ASS, Trouble measuring sensing matrix 
Message ID: 7131     Entry time: Thu Aug 9 01:26:03 2012     In reply to: 7129
Author: Koji 
Type: Update 
Category: ASS 
Subject: Trouble measuring sensing matrix 

That's a good point, but I suspect that you end up with the in-phase (0deg) as the response of the IFO is immediate compared with the dithering frequency
as long as the whitening/dewhitening are properly compensated in the digital realm.

Quote:

 Okay, so this is a little stream-of-consciousness-y, and you're going to think I'm really dumb, but I just realized that I haven't set the phase of the lockin demodulators yet.  So I think I need to dither the optics, and go through each of the sensors, and adjust the phase until the peak in TRY in DTT is maximized for the I phase, and minimized for the Q phase (since we use the I-output).  Bah.  Bad Jenne.

 

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