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    User name R. Michaels

    Log entry time 23:49:09 on November 15, 2008

    Entry number 249083

    This entry is a followup to: 249026

    keyword=notes after raster repair (TECH)

    Alex and I took swapped out raster supply #5 for #7.

    #5 was the one with an old-style 24-V supply and the R-C bridge that
    was supposed to short out transients. #7 is the one with the new-style
    beefier 24-V supply. (Both design improvements were to be tried and
    compared. There's a long history of these 24-V supplies failing.
    And it seems to always be in the middle of the night on a weekend, lol).

    Further notes:

    1. I have 10+ spare 24-V supplies in my office. Bill Gunning has them
    too. Supply #5 remains in the hall near the survey rack. Jack, can
    you repair this sometime ?

    2. The fancy HEPA-filtered cooling seems to not be working. No
    noticeable air flow and no sound. It is plugged in. We did the
    old trick of leaving the door ajar and putting a fan to cool. Can the
    techs check the fancy cooler ? (There is again a history of cooling
    appearing to reduce failure rate.)

    - Bob

    A copy of this log entry has been emailed to: segal@jlab.org,folts@jlab.org