[evlatests] Phase jumps on EA14

[Michael Rupen]

In general it would be nice if the pipeline were smarter about choosing
reference antennas.  ea14 should of course be fixed, but one bad antenna
should not produce such a "ripple effect" downstream.

The intelligent choice of a ref.ant. is not entirely trivial.
An interim solution might be to use the same antenna we use as a reference
for TelCal, which we tend to keep a careful eye on operationally.
This has the benefit of matching the reference used for phased array
work.  That reference antenna at the moment is ea12, but might more
usefully be described as the antenna on pad E8 -- one of the three
antennas which is never moved when we change configurations, and central
enough when it matters (i.e., for the more extended configurations).

There is no obvious place in the SDM proper at the moment to store the 
suggested reference antenna.  We might consider adding an element to the 
ExecBlock Table to handle this:

   Optional:
   numRefAntenna  int
   refAntenna[Nrefant], Tag[Nrefant]
   description: "default reference antennas for calibration, in order
     of preference"

We actually do send such suggestions to TelCal at the moment, so recording
that information (esp. useful for phased-array data) would seem reasonable.

            Michael

> Hi All,
>
> We are seeing phase jumps on EA14 and right now the pipeline is choosing
> EA14 as a reference antenna so, when there is a phase jump, the pipeline
> output is not usable.
>
> Is there anyway someone can go out to EA14 on Maintenance day tomorrow to
> see if this can be fixed?
>
> Thanks,
> Deb
>
>
>