[evlatests] AM889 on July 21,22,23

[Ed Fomalont]

AM889 on July 21 and 22 went well except for the usual problems.
AM889 on July 23 a little less well with a few more problems.  See below.

1.4 GHz, 2 IFs, 2 Pols, usual deep integration setup of 7 channels
5 hour experiment, 3.3 sec integration

26 antennas working.  11 and 25 out
   July 21  ante 28 out most of run
   July 22  all 26 antennas okay
   July 23. something wrong with ante 5 IF 1, R pol.  Junk correlation
   July 23  14:30 to 16:00 horrendous interference, worst at 1.385 MHz, 
Pol R.
                 All data useless (I assume this was external interference)
   July 23  Bandpass for antenna 13, IF2, L Pol has large amplitude steps
   July 23  Bandpass for antenna 14, IF1, L Pol has large amplitude steps

On all three days
   quack needed for about 15 sec on each scan
   First experiment scan of 5 minutes was junk, and then EVLA antennas 
had junk another
         5 minutes
   Ante 14 only has anomolous phase drift for second scan of 4 min (on 
all three days)
   Last 1 min of data is junk
   Phase jump on EVLA antennas after switching to X-band pointing check 
- expected and very repeatable.

Ed