[evlatests] ea17 pointing and FRM problems

[Ken Sowinski]

this is very mysterious.  I did two thongs today:

1.  With the antenna at the zenith rotate the subreflecotr to minimize
total power.  This will be close to the correct subreflector position for 
each band.

2/  Observing a clibrator rotte the subreflector to maximize ampluitude
as seen on d10 for a baseline with a referecne antenna.  If everything 
else is correct this will find the correct rotation setting.

Results.  Both methods showed that the subreflector is about right
for L and S bands, but wrong at all the other bands by about 25 degrees.
the sense of the error is that the required rotation setting is -25 
degrees away from the currently used subreflector setting.  The fact
that the sesne of the error is the same for feeds on both sides of the
feed ring suggest that it is a rotation offset.  Why L and S remain
unaffected is the mystery.