[evlatests] AM889 on July 19

[Ed Fomalont]

AM889 on July 19

1.4 GHz, 2 IFs, 2 Pols usual deep field correlator setup,
5 hour experiment, 3.3sec integration

SUMMARY OF MORE UNUNSUAL PROBLEMS:

1.  Had to quack 20 sec of each scan.  Seems longer than normal
2.  When anten 14 dropped in mid run, there was a phase jump on
    all EVLA antennas for IF1 only.  Jump was about -170 deg and
    varied about 10 deg among the EVLA antennas (RR and LL same jump)


antennas:
    11, 25 out; 26 antennas working, 2 IFs, 2 Pols
    14 out second half of run
flags:
    Lost 3 minutes on first scan for all antennas
    Lost next 4 minutes on first scan on EVLA antennas (usual problem)
    Needed to quack 20 sec on each scan (new problem?)
    Flagged one very high outlier point

Amplitude stability:
    All antennas/IF/pols with reasonable sensitivity
    Gain of ante 19 about a factor 2.0 too low.  Probably a
      simple on-line gain factor.

Phase stability:
    Little atmospheric/ionospheric variation.

    Ante 14 lost after first two hours

    BUT, phase jump seen on EVLA antennas when 14 dropped out
    on IF1, but not on IF2 (no phase change between RR and LL)
    phase jump EVLA IF1 = -170 +/- 10 deg over EVLA antennas.  Probably
        real differences of 5 to 10 deg among EVLA antennas

Bandpass:
    Looks typical, no apparent change over time


Imaging:

    Ran UVFIX

    Quick image (no faceting) of deep field gave rms= 45 uJy.  Still
limited by sources outside of field of view and w-distortion by not 
faceting.

PS: Neal, if you want any information (ie the few flags I used) about this
data set, let me know.