[evlatests] Fluke fallout

[Vivek Dhawan]

Continuing the saga of the bypassed EDFAs and project AL730:

As recent emails indicate, most of the doom & gloom I saw in the data
on the weekend was dispelled on Monday.

Revnell fixed up some of the DTS systems. Some antennas were still
showing variable amplitudes at the 2-5% level on Sunday evening but seem
to have improved by Monday noon, for reasons no one would fess up to.

The Fluke on IF B was blamed for much of the bad data that I was using
as the touchstone, i.e. VLA-EVLA data IF B was bad. This is also fixed.

To see how much of the backlog was corrupted by the Fluke phase noise,
I checked data from AL730 which has accumulated for some days.

Fluke IF B was bad on the weekend, Jan 24-25 thru about noon Jan 26.

For the 6 days before that, the Fluke looks good.

For Jan 15 and 16 (UT) the data in IF B D are mostly flagged out by the
online system, so it seems to know something is amiss, but I dont know
if the Fluke is the cause of the flags.

Mark Claussen is looking at even earlier data, and might see the start
of the problem. I will now load Jan 15 with the flags off and see if the
Fluke really is the problem.


Vivek.

p.s. AL730 used 2 subarrays and a frequency setup that makes them
minimally affected by the Fluke problem. In my opinion there is no
need to repeat any of those observations.