[evlatests] Report from AD562 -- P-band spectral line

[Rick Perley]

    A 9-hour observation at P-band was run yesterday afternoon/evening.  
I gave an initial report yesterday afternoon, and will  not repeat the 
findings here.  The issues noted there continued through the end of the 
run. 

    Of greater concern are the many 'holes' that occur in this 
database.  There are a total of 7 of these, which account for about 1/3 
of the observation duration.  The holes are of varying length, from a 
bit over an hour to only 5 minutes.  All but one of them are noted by 
the operator (see message below) as due to D10 halting and vispipe no 
data.  Ken has prescribed a recovery procedure (which clearly has 
helped, as the two longest gaps -- by far -- are the first two).  What 
is especially curious is the regularity of the failures.  According to 
the loaded data, they occurred at:
       19:47:30
       21:47:30
       23:46:10
       00:47:30
       01:05:05      this one was not noted by the operator -- perhaps a 
different problem?
       02:47:30
       03:47:30

    The probability that all (but one) these outages  have the same 
minutes and seconds for the failure time has got to be zero.zero. 

   

-------- Original Message --------
Subject: 	[Fwd: D10 halting & vispipe no data problem during AD562]
Date: 	Mon, 02 Jul 2007 08:12:30 -0600
From: 	Pat Van Buskirk <pvanbusk at aoc.nrao.edu>
To: 	Rick Perley <rperley at aoc.nrao.edu>



Here are some notes from Dave re vispipe last night. Just passing it 
along for info.

Cheers,
Pat


-------- Original Message --------
Subject: D10 halting & vispipe no data problem during AD562
Date: Sun, 01 Jul 2007 22:09:09 -0600
From: David Midgett <dmidgett at aoc.nrao.edu>
Organization: NRAO
To: Ken Sowinski <ksowinsk at nrao.edu>
CC: Barry Clark <bclark at nrao.edu>, Pat Van Buskirk <pvanbusk at aoc.nrao.edu>

Hello.  Below is a description of the problems that occurred during
project AD562 on 01July:

Program: 003D562, P-band, line mode 4 w/hanning smoothing, 5-sec.
integrations, FrontEnd BW 25mHz, BackEnd BW 6.25mHz

Symptom: D10 stopped updating and Alert "vispipe no data" displayed

Fix: Per K. Sowinski, killed 003D562 script and started continuum mode
xsysstart, then restarted 003D562 script

Important Note:  This happened at the following times(IAT): 19:47,
21:47, 23:47, 00:47, 02:47, and 03:47

Thank you for your help.

Dave
VLA Ops




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