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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.