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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


    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