[evlatests] Current L-band state

[Rick Perley]

    Some empty time was available this afternoon, so a quick check of 
system performance was done.

    Antenna 2 is out of the array this afternoon, due to some issue 
which has been reported through standard channels. 

    At L-band, I made three consecutive, identical observations of 
3C286.   I find:

    1) Overall, superb behavior.  Amplitudes and phases are stable, with 
almost no bad behavior to report. 

    2) Antenna 26, IFs B and D have be-stable phase.  The two phase 
states are separated by 65 degrees.  The two polarization are in perfect 
synchronism.  The duration of each state is from 5 to 20 seconds. 

    3) VLA antenna 4 has returned to the state with many dropouts.  As 
this antenna is heading for EVLA retrofits,  this problem will shortly 
be eliminated. 

    4) As usual, there was a global phase jump between the first and 
second scans.  There was no jump between the 2nd and 3rd. 

    5) Sensitivity is nominal on all antennas except 21A and B.  The 
poor (40% reduction) sensitivity is due to high Tsys for this receiver 
(RCP).