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    User name R. Michaels

    Log entry time 03:47:45 on November 17, 2007

    Entry number 215000

    keyword=re: DAQ repair (belated)

    We finished the DAQ repair at 2:20, and here is a belated entry.

    Alex spent a few hours on this before I arrived. The symptom was a module in ROC3
    would not respond. Alex tried swapping modules, power cycling, etc, then a different
    module would not respond. Finally found the -15V supply was bad. Perhaps the supplies
    should be checked early in the game. Anyway, I came in and confirmed the -15V was
    unstable. Jack came in and we replaced the entire power supply (all modules). Note,
    the -15V is not separable from the unit, unlike some of the other supplies. We took a
    Fastbus PS from the Transversity setup (sorry, folks). So far it seems to work fine.
    Along the way we found that the TDC in slot 4 was bad (was missing the 3rd group of
    16 channels). It was the slot Alex had swapped earlier, presumably a bad TDC. We put
    back the original TDC in slot 4.