RFI alert for Mar 2012

Subject: Re: Updated GPS-L3 (1381 MHz)  RFI Alert
Date: Mon, 19 Mar 2012 10:39:06 -0600
From: Dan Mertely 

Hello again Martha, et.al.  I have received another
email from our USSC contact in which he states:

----------------------------------------------------
Mert,

All things considered, I do not believe we'll be interfering with the
ALFALFA study on our backup days. I've taken a very close look at weather
forecasts and there's a low probability of needing the backup days and an
even lower probability that we would need the entire time span. We'll do
everything possible to avoid 1381 MHz transmissions 0000-0400Z on Thurs and
Friday this week. At this point, the only contingency that would drive
testing during that period would be a test equipment malfunction which is
unlikely.

Have a great day,
Steve
-----------------------------------------------------
So, it sounds like you are in the clear.  Happy observing!
-Mert

Subject: Updated GPS-L3 (1381 MHz)  RFI Alert
Date: Thu, 08 Mar 2012 11:48:42 -0700
From: Dan Mertely 

We have received additional detail from the US Space Command
(USSC), Colorado Springs, CO, informing the RA community of
upcoming, extended L3 test transmissions.  The observatories
should expect increased RFI @ 1381 MHz during the dates &
times indicated below (modified).

Of the fixed schedule observations showing a potential conflict,
A2669 at Arecibo appears during a potential back-up test date.
If the Arecibo schedulers believe that increased 1381 MHz RFI
will be debilitating for that observation, I could petition the
USSC for relief.

VLA & VLBA schedulers should attempt to schedule 1381 MHz use
around these times if possible.  Observing scientists should
be made aware of the increased possibility of corrupted data
on these dates and times.  VLA and VLBA operators should note
unusual L-band Tsys or total power fluctuations observed during
these times in the Operator Log forwarded to observers.

-Mert


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============================================================
GPS-L3 ALERT SCHEDULE:
============================================================
SUBJECT:  Extended GPS Satellite Testing Operations.

FREQUENCY AFFECTED:    1381.05 ± 2.5 MHz

DATE (UTC)  TIME (UTC)    Comments
(YYYYMMDD)  (HHMM)-(HHMM) (TEXT)
------------------------------------------------------------
20120320     2000 - 2400   Extended L3 tests, world-wide.     1600-2400 AST Mar 20
20120321     0000 - 0400   Extended L3 tests, world-wide.

20120321     2000 - 2400   Extended L3 tests, ww, BACKUP.     1600-2400 AST Mar 21
20120322     0000 - 0400   Extended L3 tests, ww, BACKUP.

20120322     2000 - 2400   Extended L3 tests, ww, BACKUP.     1600-2400 AST Mar 22
20120323     0000 - 0400   Extended L3 tests, ww, BACKUP.
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From the clear, high deserts of central New Mexico, The Land of
Enchantment, the VLA, and dark, dark, starry, starry nights ...
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Daniel J. Mertely
National Radio Astronomy Observatory
Interference Protection Office Engineer
P.O. Box o
Socorro,  NM  87801
(575) 835-7128
dmertely@nrao.edu
-Mert