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    User name R. Michaels

    Log entry time 11:50:04 on June28,2010

    Entry number 328910

    This entry is a followup to: 328900

    keyword=spot++ fixed (gate polarity was wrong)

    I found that the ADC gate cable for ROC4 slot 24 was reversed.

    Note, the blue LeCroy NIM/ECL fanout is different from the
    NIM/ECL fanouts that Bogdan and his students use. Beware !
    If polarity is wrong, you are integrating "forever" = saturation.
    Of course it would be better if spot gave a more sensible error
    message about this.

    Now I can almost guess what happened last night. There was access
    around midnight and work was done on PiR on ROC4 slot 23 (adjacent
    slot). So they probably knocked out the gate cable and did a few
    test runs like 1261 and realized they got no data, then restored
    the cable, but put it upside down. Just a guess.

    A peculiarity of slot 24 is that the slave light (S) never comes
    on, but that is more likely to be bad LED. I ran the standard
    Fastbus test codes: slot 24 is ok.

    Here are typical data from run 1293 just now. Pedestals are normal.

    Left HRS spot++ raw data 0 1466
    Left HRS spot++ raw data 1 1397
    Left HRS spot++ raw data 2 1417
    Left HRS spot++ raw data 3 1524
    Left HRS spot++ raw data 4 1384
    Left HRS spot++ raw data 5 1535
    Left HRS spot++ raw data 6 1424
    Left HRS spot++ raw data 7 1514
    Left HRS spot++ raw data 8 2179
    Left HRS spot++ raw data 9 2495