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Entry  Fri Feb 15 20:07:28 2013, yuta, Update, Alignment, POP path set up but AS55 is broken 
    Reply  Fri Feb 15 21:22:29 2013, yuta, Update, Electronics, AS55 replaced with POP55 PD 
    Reply  Mon Feb 18 21:43:05 2013, Koji, Update, Alignment, POP path set up but AS55 is broken AS55.pdf
       Reply  Tue Feb 19 00:21:09 2013, yuta, Update, Electronics, POP path set up but AS55 is broken 
          Reply  Tue Feb 19 05:42:28 2013, Koji, Update, Electronics, POP path set up but AS55 is broken 
             Reply  Tue Feb 19 08:06:02 2013, yuta, Update, Electronics, POP path set up but AS55 is broken 
Message ID: 8105     Entry time: Tue Feb 19 08:06:02 2013     In reply to: 8104
Author: yuta 
Type: Update 
Category: Electronics 
Subject: POP path set up but AS55 is broken 

I didn't use LED flash light. We learned from the past (elog #7355). I checked that POP55 and REFL55/165/33/11 are clearly responding to flash flight, but I didn't expect that much difference in DC gain.
I wonder why we could align AS beam to AS55 in Feb 8 (elog #8030), but not in Feb 15 (elog #8091). I will check during the pump down.

Quote:

10010 Ohm for POP55 vs 50 Ohm for AS55 (cf. http://nodus.ligo.caltech.edu:8080/40m/4763)

I wonder if you used an LED flash light, which emits no IR.

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