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Entry  Wed Aug 17 07:35:48 2022, yuta, Bureaucracy, General, My wish list for IFO commissioning 
    Reply  Fri Aug 19 14:46:32 2022, Anchal, Update, SUS, Open loop transfer function measurements for local damping loops of BHD optics 
       Reply  Sat Aug 20 20:26:10 2022, Anchal, Update, SUS, Open loop transfer function measurements for local damping loops of Core optics ALL_CORE_SUS_OLTF_2022-08-20-merged.pdf
          Reply  Mon Aug 22 14:36:49 2022, rana, Update, SUS, Open loop transfer function measurements for local damping loops of Core optics 
Message ID: 17097     Entry time: Mon Aug 22 14:36:49 2022     In reply to: 17096
Author: rana 
Type: Update 
Category: SUS 
Subject: Open loop transfer function measurements for local damping loops of Core optics 

for damping and OL loops, we typically don't measure the TF like this because it takes forever and we don't need that detailed info for anything. Just use the step responses in the way we discussed at the meeting 2 weeks ago. There's multiple elog entries from me and others illustrating this. The measurement time is then only ~30 sec per optic, and you also get the cross-coupling for free. No need for test-point channels and overloading, just use the existing DQ channels and read back the response from the frames after the excitations are completed.

ELOG V3.1.3-