[evlatests] Oscillations at C-band

[Rick Perley]

    As expected, the high visibility amplitudes and phases noted in the 
previous report are due to specific baselines at specific times. 

    For the 0555+398 data, I find:

    Baseline 27 x 28 (both polarizations, all subbands) show a ~4 second 
oscillation in phase only, pk-pk 2.5 degrees, that lasted for the first 
scan only (near 09 hours, IAT).  This is a long baseline (for D 
config).  Similar, but weaker, oscillations are seen in 5 x 28.  Nothing 
else stands out. 

    More spectacular are the amplitude oscillations, seen on (you 
guessed it!) baseline 19 x 25, starting at 14:00 IAT, and getting larger 
as time ran on.  The period here is 2 seconds, with an amplitude of 
(pk-pk) of 300 mJy on top of the 5.2 Jy source.  The amplitudes show a 
beat pattern of period 30 seconds, so there are two closely spaced 
frequencies involved here.   This is seen on all subbands and all IFs.  
No other baseline seems to be affected.