[evlatests] 6cm sensitivity, addendum

[Rick Perley]

    My report from Friday omitted the noise when observing blank sky. 
This note concerns this test. 

    The noise statistics, for both Real and Imaginary parts of the
complex visibility, show, for IF `D' (the best one):

    Antennas 14 X 16:       rms = 100 mJy.

    A subset of the best VLA antennas:   rms = 67 mJy. 

    These values are in excellent agreement with the statistics of the
amplitude seen when observing a strong source.  Thus, the high
rms for the EVLA baseline is not due to gain variations. 

    Rick