[evlatests] PDif/Psum problems

[Rick Perley]

    We ran a 'moon' test last night, as part of our efforts to promote 
linearity within our systems. 

    A very small number of systems have non-functioning switched power.  
They are:

    C-Band:  ea09 give zero PDifs, as well as PSums which did not react 
to being pointed at the moon. 

    Ka-band:  ea04 gave zero PDifs, and no change in PSum when pointed 
at the moon. 
                     ea13 gave very low PDifs  in RCP, and almost no 
change in total power when pointing on the moon.  This is clearly a 
problem in system temperature, which must be in the hundreds of K.  (LCP 
is O.K.)

    There are a number of antennas/IFs/band which are giving irregular 
PDifs -- these will be reported on separately.