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    User name chenjp,gilman,korsch

    Log entry time 13:22:00 on July23,2001

    Entry number 67256

    keyword=helicity tests, findings, changes

    We go to right arm to set up Phillips gate and delay and compare to LeCroy
    (in right arm). In summary, using both visual scalers with 1 KHz pulser, and spectrometer DAQ, we determine that Phillips has a 10^-3 asymmetry in
    pseudorandom mode, no asymmetry in toggle mode, and LeCroy has
    no asymmetry in either mode. (No asymmetry means < about 2 times 10^-4,
    uncertainty of our tests). (Bob Michaels analyzed most of data.)

    Conclusion: left arm time asymmetry in pseudorandom
    comes somehow from Phillips, would get same on right arm.
    Do not understand LeCroy / Phillips difference. Nothing
    seen on scope to indicate asymmetry.

    Note: checking LeCroy pulse widths, we see clear ~ 300 ns / 33 ms
    time asymmetry in toggle + PR modes ==> 10^-5 asymmetry.

    We add following additional info to DAQ:
    right arm, TS scaler channel 25: 1 MHz pulser
    " " " " " 27: helicity clock
    left " " " " 21: " "

    Note: the helicity clocks should allow us to count the total h+ + h- good
    pulses, allowing a determination of the number of glitches, in each helicity
    phase. The MHz pulser should allow a check of the time in each helicity phase.

    We also put a ~4 kHz pulser into T3 in the right arm, so that a fastbus readout
    false asymmetry test can be done on the right arm, as well as the test we
    already did on the left arm.