[evlatests] R/L phase differences.

[Barry Clark]

Bob's plot is not incompatible with delay cogging.  Delay moves
in steps of 0.625 ns or about 6 degrees.  What was the baseline
and hour angle?  Typical B config gaselines are of order 20
microsecs, so a delay step should occur a couple of times a
second, depending on baseline and HA.  This scatter is much
smaller than what the scatter diagram on V appeared to show.