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Entry  Tue Aug 14 00:42:40 2012, Jenne, Update, Locking, POX signal sometimes looks very funny POX_13Aug2012_LSCdisabled_pox_is_normalish.pngPOX_13Aug2012_LSCenabled_pox_is_squareish_funny.png
    Reply  Tue Aug 14 04:32:49 2012, rana, yoichi, Update, Locking, POX signal sometimes looks very funny ITMX_1028974969.bmpETMXF_1028975007.bmpETMXT_1028975105.bmpAS_1028975166.bmp
       Reply  Tue Aug 14 14:26:40 2012, Steve, Update, Cameras, cameras touched up cameras.png
          Reply  Fri Aug 17 08:33:46 2012, Steve, Update, Cameras, video cameras in the dark dark.jpg
             Reply  Fri Aug 17 09:34:27 2012, Koji, Update, Cameras, video cameras in the dark 
                Reply  Fri Aug 17 10:38:15 2012, Steve, Update, Cameras, video cameras in the dark 
             Reply  Fri Aug 17 14:45:51 2012, rana, Update, Cameras, video cameras in the dark 
                Reply  Mon Aug 20 09:49:01 2012, Steve, Update, Cameras, video cameras in the DARK onlyOSEMs.jpgOSEMsand_IR.jpgOSEMsandOplev633.jpg
Message ID: 7168     Entry time: Tue Aug 14 00:42:40 2012     Reply to this: 7169
Author: Jenne 
Type: Update 
Category: Locking 
Subject: POX signal sometimes looks very funny 

I'm trying to lock / align the Xarm, and POX 11 I looks funny sometimes.

I attach 2 screenshots so you can see what I mean.  I'm leaving them uncropped so that you can see the only thing that has changed is the LSC enable / disable button. 

The situation:

PRM, SRM, ITMY, ETMY all misaligned.  BS, ITMX, ETMX aligned so that most of the time I can't lock better than 04, bad in yaw, but very occasionally I'll get lucky and catch a 00.  When the LSC enable switch is ON (2nd attachment), the POX signal (green trace in dataviewer in both attachments) looks almost square-ish, and definitely funny.  It doesn't seem to correspond directly to flashing in the cavity (red trace in dataviewer in both attachments).  However when I disable the LSC, POX goes back to looking normal - 1st attachment.  Right around -5 seconds in the 1st attachment, I disabled the LSC.

I don't really know what this means.

Attachment 1: POX_13Aug2012_LSCdisabled_pox_is_normalish.png  668 kB  | Hide | Hide all
POX_13Aug2012_LSCdisabled_pox_is_normalish.png
Attachment 2: POX_13Aug2012_LSCenabled_pox_is_squareish_funny.png  669 kB  | Hide | Hide all
POX_13Aug2012_LSCenabled_pox_is_squareish_funny.png
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