[evlatests] Modcomp-Free Test, Friday night.

[rperley at nrao.edu]

> On Sat, 23 Jun 2007, Rick Perley wrote:
>
>>    A)  Pulsing Data.
>>
>>    At all bands and all IFs and all sources, at all times, data from
>> most VLA antennas is 'pulsing'.  There are three very clear behaviors:
>
> I had thought to blame this on loss of phase switching synchronization
> for VLA antennas, but looked at the pointing data and so no sign of
> loss of coherence in ten second integrations.  We must look elsewhere
> to explain this.  Was it present when you did the check of Barry's
> fix for the short time phase problems week before last?
>

It was present two weeks ago, as I recall showing Barry the amplitude
plots (and his saying these were clearly correlator issues).  But they
were certainly not present after the phase ramp/cup fixes.

I'm surprised to hear that reference pointing worked!  The amplitudes are
so considerably reduced on some antennas that, along with the pulsing, I'd
have thought the 10-second average would have taken it beneath the
threshold.  I'd like to review the solutions -- please remind me where
these are stored.