[evlatests] EVLA L-Band Performance

[Rick Perley]

    After the distractions of the past few days, it seemed a good time 
to do a system health check.

    Data were taken in my usual mode -- spectral line, 16 channels in 
four parallel-hand correlation (RR, LL for each of the two IFs), 
5-second averaging. 

    L-band data were taken at 1275 and 1485 MHz. 

    The five operational antennas (13, 14, 16, 18, and 24) are all 
working excellently at L-band.  There were no amplitude of phase 
peculiarities amongst EVLA antennas.   Delays are fine for all antennas. 

    Sensitivities are exactly as described in early October.  In short, 
at 1485 MHz, antennas 18 and 24 are near the best of the VLA antennas.  
Antennas 13, 14, and 16 are in the bottom third, but are still within 
expected values.  At 1275 MHz, antennas 13, 18, and 24 are the best of 
all.  Antenna 14 is near the top.  Only antenna 16 is poorer than the 
average, but still well within the VLA sensitivity norms. 

    One global phase jump was noted -- relative to an EVLA reference, 
all VLA antennas jumped by 30 degrees -- the same value was seen for 
both IFs and both polarizations.  The jump occurred within a scan!  It 
is impossible to say which array (VLA or EVLA) is responsible for the 
jump.