[evlatests] Other issues from Thursday

[Rick Perley]

    Some other problems, perhaps separate from the phase issues of the 
prior note, occurred:

    1) We had another 'concatenated scan' in the test.  This one 
combined and L-band observation with a previous P-band one.  Both are 
listed as being at P-band.  The IAT time of the missing L-band 
observation (which appears as a P-band observation) is between 22:54:18 
and 22:55:39. 

    This observation was in fact the last of my polarization test, which 
was followed by my stress test -- which began with three consecutive 
L-band observations.  Is there some connection here? 

    2)  There are more amazing curiosities in the stress test.  The 
initial observation -- at L-band -- showed an enormous phase  changes, 
every 1.66 seconds, for all antennas numbered 22 and higher, except for 
23.  The delays are not wrong -- coherence remains near normal levels -- 
and the phases within the 1.66 second durations are stable.  This 
behavior was corrected upon the 2nd of the three consecutive L-band scans. 

    3)  Completely unrelated is that 19C (only) is giving no fringe 
power at any band.  All 19's other IFs are working normally at L, C, X, 
and K bands. 

    4) A check of P-band behavior shows that antennas 14, 17, 18, 21, 
23, 24, and 26 all with decent sensitivity.  Ant 21 is down by a factor 
of 4 on all IFs, 23 is down by about a factor of 2 on IFs A and C.  All 
others are not far from VLA standards.  Antennas 11 and 19 are turned 
off.  Antennas 13 and 16 are not yet equipped.  Ant 25 was flagged, 
correctly.