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Entry  Mon Oct 5 18:34:26 2009, Jenne, Update, Adaptive Filtering, Attempts to take a TF of the OAF system OAF_TF_CORRexc_EMPHout_2.png
    Reply  Tue Oct 6 11:13:53 2009, Jenne, Update, Adaptive Filtering, Attempts to take a TF of the OAF system 
       Reply  Wed Oct 7 03:49:49 2009, rana, Update, Adaptive Filtering, Attempts to take a TF of the OAF system Untitled.png
          Reply  Wed Oct 7 19:23:49 2009, Jenne, Update, Adaptive Filtering, (Final?) PEM cabling changes 
       Reply  Wed Oct 7 07:42:55 2009, rana, Update, Adaptive Filtering, Attempts to take a TF of the OAF system 
Message ID: 2063     Entry time: Wed Oct 7 07:42:55 2009     In reply to: 2058
Author: rana 
Type: Update 
Category: Adaptive Filtering 
Subject: Attempts to take a TF of the OAF system 

I remeasured the OAF time delay using the OAF-TF template from the Templates/ directory.

Troublingly, I found the MC1 dewhitening switches set OFF - please make sure that the MC1 dewhitening is back ON after each OAF tuning so that the interferometer locking is not hosed.

The OAF-TF template had the excitation amplitude set ~20x too high. I reduced it and the coherence was still > 0.95. The phase at 32 Hz was still ~126 deg as Jenne had measured, but since the phase at DC is 180 deg, the overall phase lag is just 180-126 = 54 deg. So the delay should be 54/180 * 32 = 9.7 => 10. Luckily, Jenne is working on an instructional manual for OAF that will make all of this crystal clear.

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