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    User name Kent Paschke

    Log entry time 13:23:57 on January18,2003

    Entry number 92400

    Followups:

    keyword=What to do if feedback appears to be inactive

    If feedback appears to be inactive:

    1) all 3 control switches (visible on runbird gui) should say "enabled". If
    any say disabled, feedback has been turned off. Contact parity on-call.

    2) if charge asymmetry is not larger than 2x the quoted error (x +/- ex,
    with x > 2*ex) and charge asymmetry is greater than 10, then the timestamp
    won't update, and feedback won't act. This is known and acceptable behavior,
    and does not indicate a problem with feedback.

    3) If the feedback is not disabled (see 1 above) and should be sending
    corrections (see 2 above) then attempt this fix:

    a) if a parity run is in progress, end the run. (this does not affect
    the spectrometer runs).

    b) On the CODA gui, select File->Exit, and confirm "OK" to exit CODA

    c) logged is as "apar" on adaql1, kill all coda processes with the command
    "kcoda" (quotes indicate literals in these instructions, and are not
    part of the commands or usernames).

    d) again as "apar" on adaql1, type "rcServer &" and wait 10 seconds or
    so. You should have about four lines of text appear, ending with
    something along the lines of "run control up and running"

    e) from this same prompt, type "runcontrol" to start the parity DAQ. Follow
    usual DAQ startup instructions (connect, configure "sduality", download).

    f) start a run. This should fix the problem, and feedback should begin
    to update every couple minutes of good beam, with the exception of
    situation 2) above.

    g) be sure to halog that there was a problem!

    4) If in any case the charge asymmetry is greater than 100 ppm, something is
    wrong (feedback is off, broken, railed, of the charge asymmetry jitter is
    excessive). If the instructions above don't fix the problem, page
    parity on-call.