RFI alert Sep 2009

Note: AST = UTC-4

According to the current A2010 schedule, we will not be impacted by this alert in August or Sep2009 but we note the announced tests scheduled for early December. See below.

From: Dan Mertely 
Organization: NRAO
Date: Fri, 31 Jul 2009 12:24:01 -0600
To: vlaops@nrao.edu, vlbaops@nrao.edu, bclark@aoc.nrao.edu,
NRAO-RFI@nrao.edu, tgergely@nsf.gov, koneil@nrao.edu, rfiwatch@nrao.edu,
bob.sault@csiro.au, jsarkiss@atnf.csiro.au, rjc@jb.man.ac.uk,
rvermeulen@astron.nl, millenaar@astron.nl, alexe@astron.nl,
Tasso.Tzioumis@atnf.csiro.au, wsizemore@nrao.edu, cbeaudet@nrao.edu,
blewis@naic.edu, pwoody@nrao.edu, mdavis@seti.org, "Harvey Liszt (E-mail)
(E-mail)" , aclegg@nsf.gov, jromney@nrao.edu,
rfreund@as.arizona.edu, demerson@nrao.edu, aeer@haystack.mit.edu,
blitz@berkeley.edu, jwrobel@aoc.nrao.edu, gps-alerts@hcro.org, atac@hcro.org
Subject: New GPS L3 RFI Alert

We have been pre-alerted to the following, military GPS-L3 test
Transmissions which may cause RFI to observations scheduled for the
use of L-band (21cm) on the UTC date(s) and time(s) listed below.

These intermittent transmissions were previously unscheduled.

The 1381 MHz frequency is within the VLA L-band 21/20cm "LL"/"21",
"L1", and "L2", continuum default frequencies, and any L-band
spectral line set-up that includes 1381.05 ± 2.5 MHz.

VLA & VLBA schedulers should attempt to schedule 1381 MHz use around
these times if possible.

-Mert

1234567890123456789012345678901234567890123456789012345678901234567890
          1         2         3         4         5         6         7
======================================================================
NEW GPS-L3 ALERT SCHEDULE:
======================================================================
SUBJECT:  GPS Satellite Testing Operations.

FREQUENCY AFFECTED:    1381.05 ± 2.5 MHz

DATE (UTC)   TIME (UTC)      Comments
(YYYYMMDD)   (HHMM)-(HHMM)   (TEXT)
----------------------------------------------------------------------
20090804     1430 - 1930     Intermittent system-wide tests.
======================================================================


In addition, radio astronomy schedulers should remain aware of the
following, previously distributed quarterly RZAPS/LZAPS schedules:

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           1         2         3         4         5         6         7
======================================================================
PREVIOUSLY ANNOUNCED QUARTERLY RZAP/LZAP SCHEDULE:

SUBJECT:  3Q 2009 GPS Satellite Testing Operations.

FREQUENCY AFFECTED:    1381.05 ± 2.5 MHz

DATE (UTC)   TIME (UTC)      Comments
(YYYYMMDD)   (HHMM)-(HHMM)   (TEXT)
----------------------------------------------------------------------
20090915     1900 - 2400     RZAP/LZAP system-wide tests (Primary).
20090916     0000 - 0300     RZAP/LZAP system-wide tests (Primary).
20090916     1900 - 2400     RZAP/LZAP system-wide tests (Back-up).
20090917     0000 - 0300     RZAP/LZAP system-wide tests (Back-up).
20090917     1900 - 2400     RZAP/LZAP system-wide tests (Back-up).
20090918     0000 - 0300     RZAP/LZAP system-wide tests (Back-up).
======================================================================
SUBJECT:  4Q 2009 GPS Satellite Testing Operations.

FREQUENCY AFFECTED:    1381.05 ± 2.5 MHz

DATE (UTC)   TIME (UTC)      Comments
(YYYYMMDD)   (HHMM)-(HHMM)   (TEXT)
----------------------------------------------------------------------
20091201     2000 - 2400     RZAP/LZAP system-wide tests (Primary).
20091202     0000 - 0500     RZAP/LZAP system-wide tests (Primary).
20091202     2000 - 2400     RZAP/LZAP system-wide tests (Back-up).
20091203     0000 - 0500     RZAP/LZAP system-wide tests (Back-up).
20091203     2000 - 2400     RZAP/LZAP system-wide tests (Back-up).
20091204     0000 - 0500     RZAP/LZAP system-wide tests (Back-up).
======================================================================
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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 ...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* # * # * # * # * # * # * # * # * # * # * # * # * # * # * # * #
# * # * # * # * # * # * # * # * # * # * # * # * # * # * # * # *

Daniel J. Mertely
National Radio Astronomy Observatory
Interference Protection Office Engineer
P.O. Box o
Socorro,  NM  87801

(505) 835-7128

dmertely@nrao.edu

Old RFI alerts




Last modified: Mon Aug 17 09:01:32 EDT 2009 by martha