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User name R. Michaels
Log entry time 08:53:57 on February 09, 2009
Entry number 259993
This entry is a followup to: 259964
Followups:
keyword=re: helicity synch
The pattern observed looks like a totally random time relation between
the two crates, which is hard to believe.
We may ask Vince to check if something changed in the ADCs.
For example, the cable may be falling out or loose in the connection
and the data are right on the edge of the cuts that define high
versus low, etc. Something like that.
Another quick thing to try is power cycle all crates and see if
they get back in synch. I've seen that before (very rare, though).
Should also look at the helicity signal on a scope and see if something
changed in the cabling, e.g. a fanout which attenuated the signal going
to the ADCs causing marginal cut situation, etc.
All these things need a 1 hour access.
A copy of this log entry has been emailed to: vasulk@jlab.org