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    User name R. Michaels

    Log entry time 21:35:28 on October 28, 2008

    Entry number 245204

    This entry is a followup to: 244995

    keyword=re: offset/attenuator

    Sorry I missed this before, but the ADC for BPM/raster should have a 50 nsec gate !
    This is because millions of years ago we used dedicated VME ADCs with such a gate
    and the offset/attenuator boards were designed for that. Now our fastbus gates are typically
    250 nsec. Ok, we could modify the off/att boards, probably just resistors on the op amp.
    Worth asking Cuevas when we have a calm moment.

    Anyway, I suspect we moved the gate cable (it's a front-side input) to the "standard gate"
    due to the usual shutdown confusion and it could easily be my fault.

    If we still have saturation or dynamic-range problems you may call me in and I'll fix this
    in 20 min. But if you're happy with the data we can leave it alone. When you get data check
    if the bit resolution is adequate.

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