User name gilman
Log entry time 15:56:19 on July25,2003
Entry number 106851
keyword=helicity signal check
JP has asked me to relook at the helicity signals, given that the MPS
signal changes 25 microseconds before the helicity signal changes, with us in
delay=0 mode. (Times signals get to counting house.)
What we do for the spectrometers is send the LNE (load next event) signal
to the spectrometers "instantly" as soon as MPS goes "positive". This is now 25
usec early with respect to the change in the helicity signal.
We also delay the helicity signal by 350 usec (recall MPS is "positive"
for 500 usec). So now the delay is in effect 375 mircoseconds.
Thus, the 25 microsecond offset in delay 0 mode should not affect the DAQ, i.e.,
the delay put into the software to replay correctly. However, one might
wander when the helicity itself actually changes relative to any of these signals.
I leave that for others to determine.