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Message ID: 11836     Entry time: Wed Dec 2 03:34:30 2015
Author: ericq 
Type: Update 
Category: LSC 
Subject: SRCL OLG weirdness 

[gautam, ericq]

Since ETMX seems to have been on good behavior lately, we tried to fire the IFO back up. 

We had a fair amount of trouble locking the DRMI with the arms held off resonance. For reasons yet to be understood, we discovered that the SRCL OLG looks totally bananas. It isn't possible to hold the DRMI for very long with this shape, obviously. 

With the arms misaligned and the DRMI locked on 1F, the loop shape is totally normal. I haven't yet tried 3F locking with the arms misaligned, but this is a logical next step; I just need to look up the old demod angles used for this, since it wasn't quickly possible with the 3F demod angles that are currently set for the DRFPMI. 

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