[evlatests] Modcomp-free: L-Band

[Rick Perley]

    Extremely good data, overall.   26 antennas fringed (#11 is in the 
barn, and #23 was stowed).  Phases and amplitudes in general very 
stable.  No 'shredded' amplitudes on any IF.  No odd phases, other than 
what we expect with the correlator's delay changes, and the effects of 
the atmosphere/baselines/RT phase issues. 

    Notable problems:

    1) The first 1.25 minutes of the scan were all noise -- evidently 
the correlator was outputting data even though the antennas were slewing 
from the previous source (3c147 at P-band ) to the L-band source 
(3C84).  I thought the correlator was supposed to be turned off when the 
antennas were slewing ...

    2) Antenna 13, IFs B and D (IF2) was extremely weak -- barely 
visible fringes. 

    3) Antenna 4 had a number of large amplitude drops -- all IFs in 
parallel.  The Tsys undergoes a large jump at exactly the same time.  
These are both 'impulsive' events. 

    4) The only 'short shallow drops' were on antenna 17, IFs B and D.

    5) Antennas 24B and D, and antenna 26B are showing small-scale 
amplitude variations.  No clear origin. 

    6) Antenna 19 has no Tsys data being reported!  Can somebody turn 
this on, please?