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Entry  Tue Jul 14 00:57:11 2009, Alberto, Update, Locking, photodiode alignment check 
    Reply  Wed Jul 15 12:14:08 2009, Alberto, Update, Locking, photodiode alignment check 2009-07-15_PD9spectrumPDF.pdf
       Reply  Thu Jul 16 01:00:56 2009, Alberto, Update, Locking, PD9 aligned 2009-07-15_PD9spectrumPDF02.pdf
Message ID: 1742     Entry time: Tue Jul 14 00:57:11 2009     Reply to this: 1749
Author: Alberto 
Type: Update 
Category: Locking 
Subject: photodiode alignment check 

Since lately the alignment of the input beam to the interferometer has changed, I went checking the alignment of the beam on the photodiodea. They were all fine except for pd9, that is AS DD 199. Here the DC is totally null. The beam seems to go right on the diode but the scope on the PD's DC output shows no power. This is really strange and bad.

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