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Message ID: 1988     Entry time: Wed Nov 22 18:51:54 2017
Author: awade 
Type: DailyProgress 
Category: FSS 
Subject: Repair to south monitor daughter board D040424 (2010:007) 

Some time back (in the last two months) some damage was done to the FSS south daughter board (LIGO-D040424-B, Serial: 2010:007). This was the same issue as before (PSL:1784), the board was plugged back into the main servo board (LIGO-D040105) but the pins were misaligned by one row. We switched out the daugher board from the 40m FSS unit (2010:006) but this needs to be returned to its original unit.

I started by replacing U3 as this was the problem last time.  This seems to have resolved the issue and the monitor signals are faithfully reporting the correct buffered G=1 values as far as I can tell.

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