[evlatests] Antenna 10 azimuth servos

[Rick Perley]

    I noted last week the significant oscillation encountered when 
driving the antennas in azimuth.  Since then, I have analyzed the 
performance of all the antennas.  All but two of the antennas behave in 
the manner described last week.  The other two -- particularly one of 
them -- show a much larger oscillation and slower damping time.  These are:

    Antenna 14:  The amplitude is larger, and the decay time larger -- 
over 10 seconds to reach half amplitude. 

    Antenna 10:  The pattern here is entirely different than any other 
antenna.  The oscillation is larger (nearly 30 arcseconds, peak-peak), 
of much shorter period (3 seconds), and does not seem to be damped at 
all -- the oscillations continue throughout the entire 20 seconds spent 
at each position, with little discernible decrease in amplitude.  Sounds 
like a servo issue here.