[evlatests] pointing curiosity

[Ken Sowinski]

There was a pointing run last night which was rather boring
except for the Q band results.  All the VLA antennas, except
for VA08, provided no solutions; all the trials were rejected
on the grounds of estimated beam width.  When the threshold
was increased by about 10 percent solutions were provided
for all the VLA antennas and all antennas wanted a change
in azimuth collimation of about +0.25 arc-min.  Collimation
at all other bands, including K band, were reasonable.  I
do not believe this result and have not changed any of the
VLA Q band collimation terms.

All the EVLA antennas, except EA14, were well collimated
at Q band.  Collimations were updated for EA14 at C and
Q band.

There has been an earlier collimation run, without Modcomps,
claiming that all the VLA antennas were fine.

It seems we must have broken something between August 30
and September 22.  It cannot be subreflector rotation, for
a small change there would move the beam mostly in elevation.
Can anyone thing of something we changed which affects
azimuth pointing, but only at Q band, and onlt for VLA
antennas?