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    User name mcnulty

    Log entry time 12:09:14 on June 08, 2010

    Entry number 325265

    keyword=Investigation of counting DAQ quartz det signal problems in Rarm

    Made opportunistic access to trouble shoot the problem seen during the
    last Q2/alignment study.  The problem was the lower (amplified) quartz
    signal was crazy-looking and the upper quartz signal was not well
    separated from pedestal.
    
    I found the amplified signal cable connector was sagging at the fastbus
    ADC; I re-inserted it and the problem is fixed.
    
    I noticed the upper quartz signal was working, but had a huge 10ch
    pedestal.  I examined 5 other channels in the group of 16 (of the ribbon
    cable) and found all of them to give between 9 and 10ch for pedestal RMS.
     This is perhaps the problem since the quartz signal is only 30 or so
    channels above pedestal...a 10ch pedestal is bad.  I did not have time to
    try another group of channels or another ADC slot, but we should perhaps
    do this during an extended down.
    
    I restored all signal pathways and HV values to their nominal
    settings...set for integration DAQ mode.