[evlatests] June 30 tests, part 1

[Ken Sowinski]

> Just for fun I measured delay errors at 50 MHz in both line and
> continuum modes.  They are quite different, perhaps because of
> peculiarities of either the VLA or EVLA bandpasses.  Using antenna 6
> as a reference antenna the continuum delay errors were essentially
> zero.  In line mode the apparant delay error between 14A and 16A was
> 20 ns.
>      IFA  IFC
> 14   +10   -4
> 16    -4   -4

Rick just pointed out that this is easily explained by knowing
that line channel 0 represents the inner 3/4 of the bandpass
while the continuum measurement is over the entire bandpass.
This and the 'button hook' can explain such a large difference.

Ken