FDC test: common stop vs common start

[Elliott Wolin <wolin@jlab.org>]

Hi,

Kindly send me you opinions on whether to run the FDC tests using the common start or 
common stop mode of the LeCroy 1877S TDC.

I'm tempted to use common start because the trigger signal comes very quickly (just 
scintillators and some fast logic), it is simpler to understand and analyze, and I don't 
have to record the trigger signal in a TDC channel.

The question is whether the earliest cosmic ray and FDC chamber signals arrive late enough 
after the trigger (commmon start) so that the TDC records them properly.  If this can't be 
guaranteed then common stop must be used.


				Sincerely,
					Elliott


================================================================================

      Those who sacrifice freedom for small gains in security deserve neither
                             freedom nor security

      Science plays a major role in satisfying the minor needs of mankind

                Secular man, by playing God, becomes the devil


Elliott Wolin
Stalag 602-11
Gulag ARC-ipelago

================================================================================