From sth@tycho.usnogps.navy.mil Fri Apr 30 14:53:39 EDT 1999
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From: Steven Hutsell
Message-Id: <199904301851.SAA06876@tycho.usnogps.navy.mil>
Subject: 298/0000
To: jimr@maia.usno.navy.mil
Date: Fri, 30 Apr 1999 18:51:58 UTC
Cc: bill@tycho.usnogps.navy.mil
X-Mailer: Elm [revision: 212.4]
Status: RO
Hi Jim:
Another AMC TR 1 PPS jump, between 0000 and 0023 UTC, this morning, MJD 51298.
Looks like about -7665 ns.
Steven
From jimr Tue May 4 12:50:35 EDT 1999
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From: Jim Ray (USNO 202-762-1444)
Message-Id: <199905041650.MAA17226@maia.usno.navy.mil>
Subject: update on AOA receiver at Schriever AFB
To: djkforaoa@aol.com (Don Kennedy (AOA)),
aoa@aoa-gps.com (Allen Osborne Assoc.)
Date: Tue, 04 May 1999 12:50:33 EDT
Cc: bill@tycho.usnogps.navy.mil (Bill Bollwerk (USNO/TS)),
sth@tycho.usnogps.navy.mil (Steven Hutsell (USNO/TS)),
paul@tsee2.usno.navy.mil (Paul Wheeler (USNO/TS)),
miranda@tango.grdl.noaa.gov (Miranda Chin (NOAA/CIGNET)),
linda@gracie.grdl.noaa.gov (Linda Nussear (NOAA/CIGNET)),
jimr@maia.usno.navy.mil
X-Mailer: Elm [revision: 212.4]
Status: RO
ATTN: Don Kennedy
Jim Holston
To update my message of 13 April 1999, concerning the operation of the
USNO SNR-12 ACT receiver (S/N 247-U) recently installed at Schriever AFB,
listed below are the anomalies we have observed (ignoring problems
associated with PRN27 tests around the period of 25 March 1999):
* 26-Mar-99 spontaneous clock reset of +245 ns at ~01:10 UTC
* 31-Mar-99 receiver stopped tracking at ~00:10 UTC
* 09-Apr-99 receiver stopped tracking at ~00:09 UTC
* 30-Apr-99 spontaneous clock reset of -7625 ns at ~00:10 UTC
It appears that there is some sort of problem which occurs from time
to time shortly after midnight.
Has there been any progress in diagnosing the source of this problem?
I understand that SNR-12 ACT receiver S/N 245-U is ready for shipment
by AOA. Without further information there is no way to know whether
to ship it to USNO, Washington, as orginally planned, or to send it to
Colorado Springs to replace unit 247-U (and return 247-U to AOA for
repairs).
Thanks for your assistance,
--Jim
=========================================================================
Jim Ray e-mail: jimr@maia.usno.navy.mil
U.S. Naval Observatory, EO Dept. phone : 202-762-1444
3450 Massachusetts Avenue, NW fax : 202-762-1563
Washington, DC 20392-5420
=========================================================================