[evlatests] EVLA L-band Behavior

[Rob Long]

My first thought would be that we have an L302-2 issue to look into as 
Rick suggests.  Did the synthesizer appear to be functioning properly 
during this time?

Rob

Rick Perley wrote:
> 
>    The single exception is antenna 13, IFs B and D.   There was a large 
> (> 100 degree)
> phase jump on IFs B and D, at 17:19:13 IAT.  The change was not 
> instantaneous --
> a stable phase was regained only after two records (3.3 second averaging 
> was used). Nearly all the change occured in the first (and the amplitude 
> was severely depleted for
> that one record).  About 20 degrees more change was seen in the 2nd.   
>    Careful inspection of the amplitude stability shows that we are 
> getting 3% drops
> in antenna 13 amplitude, on IFs B and D only.  When this happens, it 
> occurs on every
> 3rd integration -- that's exactly 10 seconds separation.  But the effect 
> is not seen all
> the time:  every 3rd record was weak by 3% in amplitude over 20 seconds,
> followed by 20 seconds where all was good, then 20 seconds when every 3rd
> record was down, etc.
>    Gotta be a L302-2 issue?
>