[evlatests] AM889 -- Sunday

[Rick Perley]

    Had a few moments to spare, came in to check the early part of this 
observation.

    L-Band, Mode '4', 3.3sec averaging. 

    Initial scan on 3C48 mostly flagged as good -- but is actually all 
noise. 

    Antennas 6, 7, 15, 22, and 26 generally flagged as bad, but are 
actually good.  Ed should fill with flags off, then use QUACK and UVFLG, 
as needed ... 
    Including those nominated above, all 27 antennas are working.  
However, 13D is still giving no fringes. 

    Phase stability looks just fine (including on the flagged antennas). 

    Very strange significant amplitude gain changes seen on some IFs, 
when on the calibrator scans.  These are smoothly varying, by typically 
10 - 30%, on timescales of one to perhaps a few minutes.  It seems to be 
on both VLA and EVLA antennas, but not all of them (on the short bits of 
data I got to look at).  I've not seen anything like this before.  Ed 
should check the Tsys values to see what these are doing.