[evlatests] report on K-band observing from last Saturday, April 15

[Claire Chandler]

I requested the available EVLA antennas for my K-band spectral line 
observations last Saturday.  I was also using PT, so I had only 13 and 14 
included in my experiment.  I found the following:

Antenna 13:

    - all the data were flagged by the online system

An EVLA antenna is flagged if there is no switched power, it is not on 
source, or if the subreflector position is wrong, so I re-loaded all data 
including those flagged:

    - the Tsys values are sensible, so the switched power appears to have
 	been fine
    - reference pointing at X-band gave good solutions
    - data must have been flagged due to a poor subreflector position
 	consistent with seeing some (but not much) evidence of phase
 	coherence on my phase calibrator at K-band, but the amplitudes
 	dropped after a pointing measurement at X-band and never
 	recovered.  Is the subreflector sticky?  (But note that even the
 	K-band data before the pointing were flagged online.)

Antenna 14:

A first glance indicates that the data are similar in quality to the VLA 
antennas, but I have not gone through and calibrated it yet.  There is 
something curious on the 14-PT baseline not seen on any other baselines 
with 14 or PT.  I am using fast switching and I see low amplitudes when it 
first switches to the calibrator, which recover and look normal after a 
few 3-sec integrations.

Claire