[evlatests] Pointing failure for ea14

[Rick Perley]

     I ran the last ACU test this morning.  Something bad occured to ea14.

     The test is simply to run the referenced pointing routine (cycles 
through the half power points in the four cardinal directions, plus one 
on-source observation), with 20 seconds per point.
     At x-band, ea14 'went crazy'.  I attach a plot, showing the power 
amplitudes from ea21 (bottom) and ea14 (top).

     ea21 shows normal (very nice) behavior.  The flat-top traces at 0 
dB is the power when on-source.  Between these are four flat powers near 
-3 dB -- these are the four half-power positions.

     ea14, upon reaching the third half-power point (an offset in 
azimuth) started heading off 'somewhere else', ending up many arcminutes 
away from the intended position.  It eventually recovered its senses, 
and got back on source near the end of the cycle (right hand edge).

     This was at C-band.  No other antenna behaved this way.

     I have L, X, and Ku band data also -- yet to be reduced.  Stand by ...


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