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    User name brads

    Log entry time 21:14:39 on June 07, 2008

    Entry number 241508

    keyword=Controlled Access activity

    There was a CHL trip around 4:30pm. After waiting a bit we decided to request an opportunistic controlled access.

    Part way through the access Left Q1 tripped. Spent some time troubleshooting that problem. Got it going again. Guy made sure the quad was cycled and reset to the correct momentum.

    Eli hooked up his prototype paddles. They're on a chair near the inner RHRS bogies on the beamline side. 3 of the 4 PMTs were confirmed to work (one dead). Signals patched up to the second floor counting house. HV channels used are crate 2002, slot 9, channels 0--3; all set to -1200V.

    I went down to cross check an number of items associated with the Cerenkov. Items of interest:
    - confirmed signal cable map from PMT through to ADC input with a pocket pulser (fixed one bad patch cable on 14).
    - attempted to put the 10x amplifiers back in at the front-end but they immediately induced 30--40mV P-to-P noise. Left them out (signals run straight from the PMT through patch panels and analog delay into ADC
    - baseline on PMT signals is extremely clean, even after delay.
    - re-re-re-check gate timing at ADC using EDTM signal. Shifted my gate 30 ns earlier just to be safe
    - finally put PMTs 17--20 on the black 50ohm ribbon cable like all the rest.
    - left PMT 5 and the ADC gate plugged into the scope so we can view them upstairs