40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
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Entry  Fri Feb 20 19:09:48 2015, ericq, Update, ASC, QPD frontend code unified 
    Reply  Mon Feb 23 08:06:59 2015, rana, Update, ASC, QPD frontend code unified 
    Reply  Thu Mar 5 20:44:30 2015, Jenne, Update, SUS, damprestore script updated 
    Reply  Mon Mar 9 18:10:59 2015, Jenne, Update, ASC, Oplev filters re-copied 
    Reply  Sat Mar 14 00:12:18 2015, rana, Update, SUS, Oplevs huh? burp.png
       Reply  Mon Mar 23 13:27:33 2015, ericq, Update, SUS, ITMX oplev quadrant gains unbalanced olsum.png
          Reply  Fri Apr 3 14:57:38 2015, manasa, Update, SUS, BS oplev BS_oplev_Apr3.png
             Reply  Fri Apr 3 15:15:55 2015, Steve, Update, SUS, BS oplev 
                Reply  Fri Apr 3 19:35:14 2015, Jenne, Update, SUS, BS oplev centered 
Message ID: 11201     Entry time: Fri Apr 3 19:35:14 2015     In reply to: 11200
Author: Jenne 
Type: Update 
Category: SUS 
Subject: BS oplev centered 

I think that this happens when the beam gets too close to the edge of the QPD.  We see this regularly in the ETMs, if they've been kicked a bit, but not enough to trip the watchdogs.  I think it might be the step/impulse response of the RES3.3 filter, which rings for almost 20 seconds. 

Anyhow, I've just recentered the BS oplev.  It was at -21urad in pitch, and had more than 400 counts on the top two quadrants, but only about 100 counts on the bottom two.  Now it's around 300 counts on all 4 quadrants.

As a totally unrelated aside, I have installed texlive on Donatella, so that I could run pdflatex.

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