[evlatests] L-Band Performance -- continuned

[Rick Perley]

    As indicated by Ken, we spent an hour repeating the sensitivity test 
reported earlier today, sweeping the system from 1275 to 1750 MHz.  We 
used 3C147, whose spectrum is well known.  Attached is the (properly 
formatted?) results. 

    The 'bottom line', is that all four working EVLA antennas show a 
large drop in sensitivity from low to high frequencies.  It is noted 
that rather than a continuous slide, the sensitivity loss transitions 
around 1400 MHz.  Antenna 13 remains the one with the biggest loss (a 
factor of nearly two), the others are all about the same. 
    Ken noted that the power levels, as judged by sampler statistics, 
remained good throughout, except for 13, which was very low at 1750 
MHz.  (If I have repeated his verbal report incorrectly, he can correct 
my errors in a separate note).

    One other observation was made -- all the VLA antennas show 
sensitivity loss also with increasing frequency!  The loss factor, 
however, is considerably less than that for the EVLA. 

    Despite my trust in AIPS weights, I plan to do a sky noise test in 
the near future, to confirm these conclusions. 

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