RFI alert for May, June, Sep, Dec 2014

Date: 2014-03-31 12:43
From: Dan Mertely 

We have received notice 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.  This testing is related to pre-scheduled,
quarterly testing of L3 functionality and the expected on-orbit
checkout of the new GPS 2F-6 SV.  The GPS 2F-6 launch is
currently scheduled for 20140515.

(These extended-duration tests are in addition to the regular,
daily short-duration (< 180 sec/day) GPS-L3 tests allowed for in
the USAF/NSF MOU.)

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.

Please contact me for coordination should any of these dates
and times conflict with planned radio astronomy observations.

-Mert

============================================================
GPS-L3 ALERT SCHEDULE:
============================================================
SUBJECT:  GPS Quarterly tests.

FREQUENCY AFFECTED:    1381.05 ± 2.5 MHz

DATE (UTC)  TIME (UTC)    Comments
(YYYYMMDD)  (HHMM)-(HHMM) (TEXT)
------------------------------------------------------------
20140520     2100 - 2400  Quarterly L3 tests, Primary, CONUS+.
20140521     0000 - 0500  Quarterly L3 tests, Primary, CONUS+.

20140521     2100 - 2400  Quarterly L3 tests, Back-up, CONUS+.
20140522     0000 - 0500  Quarterly L3 tests, Back-up, CONUS+.

20140522     2100 - 2400  Quarterly L3 tests, Back-up, CONUS+.
20140523     0000 - 0500  Quarterly L3 tests, Back-up, CONUS+.
------------------------------------------------------------
SUBJECT:  GPS 2F-6 SV on-orbit tests (preliminary schedule).

FREQUENCY AFFECTED:    1381.05 ± 2.5 MHz (intermittent)

DATE (UTC)  TIME (UTC)    Comments
(YYYYMMDD)  (HHMM)-(HHMM) (TEXT)
------------------------------------------------------------
20140610     1800 - 2400  GPS 2F-6 on-orbit ck, Primary, CONUS.
20140611     0000 - 0400  GPS 2F-6 on-orbit ck, Primary, CONUS.

20140611     1800 - 2400  GPS 2F-6 on-orbit ck, Primary, CONUS.
20140612     0000 - 0400  GPS 2F-6 on-orbit ck, Primary, CONUS.

20140612     1800 - 2400  GPS 2F-6 on-orbit ck, Back-up, CONUS.
20140613     0000 - 0400  GPS 2F-6 on-orbit ck, Back-up, CONUS.
------------------------------------------------------------
Look-ahead for the rest of 2014 (Preliminary):

FREQUENCY AFFECTED:    1381.05 ± 2.5 MHz

DATE (UTC)  TIME (UTC)    Comments
(YYYYMMDD)  (HHMM)-(HHMM) (TEXT)
------------------------------------------------------------
20140909     2000 - 2400  Quarterly L3 tests, Primary, CONUS+.
20140910     0000 - 0400  Quarterly L3 tests, Primary, CONUS+.

20140910     2000 - 2400  Quarterly L3 tests, Back-up, CONUS+.
20140911     0000 - 0400  Quarterly L3 tests, Back-up, CONUS+.

20140911     2000 - 2400  Quarterly L3 tests, Back-up, CONUS+.
20140912     0000 - 0400  Quarterly L3 tests, Back-up, CONUS+.
------------------------------------------------------------
20141202     2000 - 2400  Quarterly L3 tests, Primary, CONUS+.
20141203     0000 - 0400  Quarterly L3 tests, Primary, CONUS+.

20141203     2000 - 2400  Quarterly L3 tests, Back-up, CONUS+.
20141204     0000 - 0400  Quarterly L3 tests, Back-up, CONUS+.

20141204     2000 - 2400  Quarterly L3 tests, Back-up, CONUS+.
20141205     0000 - 0400  Quarterly L3 tests, Back-up, CONUS+.
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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