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    User name Bob/Kalyan

    Log entry time 23:18:52 on December 04, 2008

    Entry number 252064

    This entry is a followup to: 252054


    keyword=re: negative deadtime

    While working on the original problem we noticed that the bigbite scaler which
    is not gated by target or beam helicity, is counting wierd. Looks like nearly a factor
    of two too high. This seems to be an unrelated problem, however.

    Coming to the original problem ....

    It's been confirmed that T3 is the culprit.

    If we put ps3=20 we get crazy deadtime (-1600 %), and if ps3=1 we get a reasonable
    deadtime. The trigger supervisor (TS) readbacks of the prescale registers in event type 120
    look correct, but the TS is acting "as if" it has a ps3=1 even if ps3=20. We think that
    power-cycling the TS is worth a try.