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Entry  Wed Sep 23 17:32:37 2009, rob, AoG, Computers, Gremlins in the RFM 
    Reply  Wed Sep 23 20:02:11 2009, Jenne, AoG, Computers, Gremlins in the RFM 
Message ID: 1996     Entry time: Wed Sep 23 20:02:11 2009     In reply to: 1994
Author: Jenne 
Type: AoG 
Category: Computers 
Subject: Gremlins in the RFM 


A cosmic ray struck the RFM in the framebuilder this afternoon, causing hours of consternation.  The whole FE system is just now coming back up, and it appears the mode cleaner is not coming back to the same place (alignment).


rob, jenne

 Jenne, Rana, Koji

The mode cleaner has been realigned, using a combination of techniques.  First, we used ezcaservo to look at C1:SUS-MC(1,3)_SUS(DOF)_INMON and drive C1:SUS-MC(1,3)_(DOF)_COMM, to put the MC1 and MC3 mirrors back to their DriftMon values.  Then we looked at the MC_TRANS_SUM on dataviewer and adjusted the MC alignment sliders by hand to maximize the transmission.  Once the transmission was reasonably good, we saw that the spot was still a little high, and the WFS QPDs weren't centered.  So Koji and I went out and centered the WFS, and now the MC is back to where it used to be.  The MC_TRANS QPD looks nice and centered, so the pointing is back to where it used to be.

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