[evlatests] L352 health report.

[Ken Sowinski]

>
> 18: Not too bad, only a small residual slope. But the phase wrap
>    in the meter at ~16:34 caused a jump of ~90deg which persisted
>    for the last hour, and the phase slope changed sign there too,
>    though the meter reading did not change slope.

I noticed long ago that the average phase measuremnt
does not properly deal with a phase wrap.  We should make
it do so.  RT phase wrap will have to be dealt with,
either in the L352 or the executor.  Below is the note
I wrote then; nothing was done in repsonse as far as
I know.


>From ksowinsk at aoc.nrao.edu Tue Jun  6 18:39:51 2006
Date: Tue, 6 Jun 2006 17:39:50 -0600 (MDT)
From: Ken Sowinski <ksowinsk at aoc.nrao.edu>
To: Pete Whiteis <pwhiteis at nrao.edu>, Vivek Dhawan <vdhawan at nrao.edu>, Keith Morris <kmorris at nrao.edu>
Cc: Ken Sowinski <ksowinsk at nrao.edu>
Subject: RT phase wrap


Below is a small excerpt from a log which samples Az, EL
average RT pahse and weather station temperature every
ten seconds.  Th excerpt includes a few records around
the time whem the RT phase wraps through 0.0 to 0.999...
Note the value of 0.79996.  This is wrong and is caused,
I think, by averaging over the wrap without noticing that
the wrap occurred.  It would be nice I thing If the average
properly took account of the wrap.  The easy way is to reset
the average whenever a wrap occurs in either direction.  The
harder way is to unwrap the fast samples before doing the
averaging.

We might want to consider whether the RT phase average ought
to count wraps rather than reducing the result to the first
turn.

Ken



53892.903216  117.99351  41.06758   0.00013  31.78947
53892.903332  118.00381  41.03599   0.00010  31.47368
53892.903448  118.01273  41.00544   0.00008  31.15789
53892.903565  118.02097  40.96424   0.00007  30.84211
53892.903681  118.02784  40.93574   0.00005  30.84211
53892.903801  118.03711  40.90485   0.00002  30.84211
53892.903917  118.04638  40.87360   0.00003  30.73684
53892.904036  118.05565  40.84305   0.79996  30.73684
53892.904157  118.06561  40.81112   0.99991  30.73684
53892.904276  118.07522  40.77953   0.99987  30.73684