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Entry  Wed May 13 02:53:12 2009, rob, Summary, lore, Channel Hopping: That ancient enemy (MC problems) 
    Reply  Wed May 13 14:43:29 2009, rob, Summary, lore, Channel Hopping: That ancient enemy (MC problems) MC3sidemon.png
       Reply  Wed May 13 21:15:04 2009, rana, Summary, SUS, Channel Hopping: That ancient enemy (MC problems) 
          Reply  Thu May 14 00:15:39 2009, rob, Summary, SUS, Channel Hopping: That ancient enemy (MC problems) sidemon.png
             Reply  Thu May 14 15:28:28 2009, steve, Summary, SUS, April 24 earthquake effect on MC2 eq042409.jpg
             Reply  Thu May 14 16:07:20 2009, pete, Summary, SUS, Channel Hopping: That ancient enemy (MC problems) mc3_5days.jpg
Message ID: 1579     Entry time: Wed May 13 02:53:12 2009     Reply to this: 1582
Author: rob 
Type: Summary 
Category: lore 
Subject: Channel Hopping: That ancient enemy (MC problems) 

We were stymied tonight by a problem which began late this afternoon.  The MC would periodically go angularly unstable, breaking lock and tripping the MC2 watchdogs.  Suspicion fell naturally upon McWFS.

Eventually I traced the problem to the MC3 SIDE damping, which appeared to not work--it wouldn't actually damp, and the Vmon values did not correspond to the SDSEN outputs.  Suspicion fell on the coil driver.

Looking at the LEMO monitors on the MC3 coil driver, with the damping engaged, showed clear bit resolution at the 100mV level, indicating a digital/DAC problem.  Rebooting c1sosvme, which acquires all the OSEM sensor signals and actually does the side damping, resolved the issue. 

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