[evlatests] 20dec05 0615-0815 IAT

[Michael Rupen]

I added antennas 14 and 16 (successfully :) to AR570 this morning, 2 hours
at 4/6/20cm (0615-0815 IAT on 20dec05), standard continuum (apart from using 
OBS' L1 setup for 20cm to avoid RFI).  A quick look at calibrator phases vs. 
time reveals:

* All IFs give reasonable phases (and phase scatter) except
   ant. 16 at
     6cm: IF BD look like noise
    20cm: IF B  looks like noise

* I see Chris' phase jumps following band changes at 4 and 20cm, both
   antennas, all working IFs.  I can't tell whether this occurred at 6cm
   due to the observing setup.  Phases on a given source seem stable
   otherwise; mostly this is fast switching though.

I'll be doing a few other "standard" checks and sensitivity comparisons.
I plan to do these sorts of sanity checks regularly during AR570, which
observes every week or so.  If there's any statistic or check that you think 
would be especially valuable from this, let me know.

I've tried this adding-in of EVLA antennas now 4 times, with 2 successes and
2 failures. The failures are noted in the log, and lead to random noise on the
relevant baselines (not flagged alas), with the rest of the baselines
apparently (from a cursory examination) ok.

     -- Michael