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Entry  Tue May 5 05:16:12 2009, Yoichi, Update, Locking, DC Readout and DARM response DARM-TF.png
    Reply  Tue May 5 08:26:56 2009, rob, Update, Locking, DC Readout and DARM response 
       Reply  Tue May 5 11:44:33 2009, rob, Update, Locking, DARM response DARMtf_nospring.pngDARMtf_demodphases.png
Message ID: 1548     Entry time: Tue May 5 11:44:33 2009     In reply to: 1545
Author: rob 
Type: Update 
Category: Locking 
Subject: DARM response 

Here's the RF DARM optical response, on the anti-spring side, from optickle. Note that for the f1 sideband, changing the demod phase mostly adjusts the overall gain, while for the f2 sideband a change in demod phase alters the shape of the response. This is the quadrature-selecting power of using a single RF sideband as a local oscillator.
Attachment 1: DARMtf_nospring.png  17 kB  | Hide | Hide all
DARMtf_nospring.png
Attachment 2: DARMtf_demodphases.png  21 kB  Uploaded Tue May 5 14:31:54 2009  | Hide | Hide all
DARMtf_demodphases.png
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