[evlatests] P-band status

[Rick Perley]

    A short observation was taken early this morning for the ongoing 
'flux densities' effort. 

    Data quality continues to improve.  Here's the status:

    Antennas 17 and 22 were out of the array. 

    1) Swapped Polarization:  ea06

    I swapped the polarizations in software.  Subsequent statements 
reflect this change.

    2) Weak/dead polarizations: 
                ea06R  (down by a factor of 15 in power)
                ea25L  (down by a factor of over 400)
                ea13L  (down by a factor of a few, and also highly 
variable in gain)
                ea04L  (down by a factor of about 2). 

    3) Unsteady or bizarre behavior:

                ea13L  (as noted above)
                ea19L  highly variable -- hard to summarize.

    4) Switched power status:

                Nearly all antennas give PDif values between 0.1 and 0.6 
counts.  Exceptions are:

               ea13 (R and L)  and ea25 (R and L)  Zero-mean PDif -- 
means no power is being switched in. 
               ea01L     PDif too low by a factor of ~ 30
               ea02L     PDif low by a factor of ~ 20
               ea19L     PDif down by a factor of 10, and also doesn't 
work a lot of the time.  (zero mean).
               ea20L     PDif low by a factor of 10. 

    5) Polarization status:

              Much improved!  All the really high polarization antennas 
are much better.  
              The list of high polarization antennas is now:  (all have 
X-pol between 10 and 25%, mostly at the low end):      ea11 (the worst 
at 25%), ea04, ea15, ea20, ea26 and ea28. 

               On the other side of the coin, ea01, ea03, ea05, ea08, 
and ea21 have cross-polarization less than 5% on their mutual baselines. 

    6) Power setup. 

    This SB had Ken's magic incantations added.  These worked 
*beautifully*, except for ea19L, which was in a 'bad state' when the 
power settings were made -- resulting in it having a power about 15 
times too high.