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    User name Paschke/RM

    Log entry time 06:28:52 on June30,2002

    Entry number 87064

    keyword=Summary, source feedback tests


    Feedback systems test, round 2.

    Now featuring the "common" PZT mirror (i.e. the old mirror shared by all halls)
    Returned BPMs to forced gain (iocse9=950, iocse10=1140), turned FFB off,
    and went to 60 microAmps.

    I should note that the parity daq integrate time is set to 12000 (sorry, riad).
    The injector daq saturates at this setting, so we oversample by 2, with IT=6000.

    Got started a bit late after G0 cavity tests.

    time.......run#....inj#..V_IA...V_x...V_y....
    00:35....1375....299......5.0.....5.0....5.0......
    auto gain on bpms, because forced gain was doing us no good.
    .............1376... to check BPM gains
    01:38....1377....301......5.0.....5.0....5.0......
    02:00....1378....302......5.0.....1.0....5.0......
    02:18.... beam off to do quick pedestal runs. We use forced gain
    to match bpm gains to autogain values at 60 microAmp.
    run 1379 (inj303)... ioc10: x:900, y:800.......ioc09: x:1600, y:1800
    run 1380 (inj304)... ioc10: x:1000, y:1400...ioc09: x:1000, y:1000
    then we use the gain settings with beam, to calibrate the bpm wiresums
    with bcm readings (ambitious analysis project here). 60
    run 1381 (inj305)... ioc10: x:1000, y:1400...ioc09: x:1000, y:1000
    run 1382 (inj306)... ioc10: x:900, y:800.......ioc09: x:1600, y:1800
    Back to our originally scheduled programming, with AUTOGAIN on bpms
    02:35....1383....307.......5.0.....9.0....5.0......
    02:48....1384....308.......5.0.....5.0....1.0......
    03:01....1385....309.......5.0.....5.0....9.0......
    03:15....1386....310.......5.0.....5.0....5.0......
    03:28....1387....311.......1.0.....5.0....5.0......

    Attempting feedback. The original pzt gains are too low for Y, so I
    multiplied response parameters by 4.
    03:42...1388....312........5.0....5.0....5.0...(<- starting values only)

    Notes by R. Michaels now:
    Long feedback run 1388. Not stopping Parity DAQ in hall A.
    04:25 At injector we moved bcm3 to a tee (instead of linear fanout) and
    changed oversampling to 10. Start run 313(inj).
    04:37 Adjusted integ. time @ inj. to 1000, start run 314.
    05:06.....stopped for QE measurement
    Feedback turned off (in control.db)
    We will re-do the PZT calibration to check stability of matrix.
    .......................................IA......X......Y
    05:12....1389....315.......5.0.....5.0...5.0
    05:25....1390....316.......5.0.....1.0...5.0
    05:36....1391....317.......5.0.....9.0...5.0
    05:47....1392....318.......5.0.....5.0...1.0
    05:58....1393....319.......5.0.....5.0...9.0

    Next we will do a "bull's eye scan", i.e. controlled beam movement,
    at injector to check DAQ of BPM 1I04 and 1I06 in 100 keV region
    The Faraday cup is inserted, to avoid problems downstream.
    Inj. run......Nominal position (EPICS)
    ......................X..............Y
    320..............+2 mm........0
    321..............-2...............0
    322...............0...............+2 mm
    323...............0..............-2
    Aha ! The steering coil 1H05H,V was between 1I04 and 1I06. So, we will
    next move a coil 1I02H,V upstream of 1I04.
    324..............+2..............0
    325...............0..............+1 mm (cannot reach 2)

    06:30 End of tests. Next, we will tune for 5 pass beam.
    At 08:00 there will be access for radiation measurements and
    continuation of HAPPEX detector installation.