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User name brads
Log entry time 17:50:16 on November 18, 2008
Entry number 249583
keyword=T7 (BB Cerenkov-only) unplugged from Trigger Supervisor
At Xin's request I unplugged the twisted-pair T7 (BB Cerenkov only)
trigger signal running to the Trigger Supervisor (unplugged at the
NIM-ECL converter immediately upstream of the TS). The T7 signal _does_
still run into the scalers and TDC (so you will still see rate on the
xscaler display), but no triggers will be handled by the TS regardless of
prescales. Apparently it was causing increased deadtime, even when it
had the max prescale value at the TS. (I thought the max prescale value
was special-cased in the TS CRL and caused the trigger to be disabled...
perhaps it's '0'? Or maybe I just imagined that feature...)
Anyway, T7 is not a meaningful trigger right now. All I want is the
scaler information (which is still present).
The unplugged end of the cable (red-beige pair) is clearly labelled with
a '7' and was tucked in with the bundle running to the TS.
A copy of this log entry has been emailed to: xqian, kalyan