Message-ID: <008369CA8EDAD311BE9500A0C9D854B4AEA605@naiad.usno.navy.mil>
From: powers.edward@usno.navy.mil
To: igsmail@igscb.jpl.nasa.gov
Subject: [IGSMAIL-3992]: AMC2 station modifications
Date: Wed, 17 Jul 2002 16:31:27 -0400
Sender: owner-igsmail
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IGS Electronic Mail      17 Jul 13:39:52 PDT 2002      Message Number 3992
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Author: Ed Powers
 
Dear Colleagues,
 
The data collection computer for station AMC2, located at the Alternate
Master Clock of the U. S. Naval Observatory (USNO), failed on June 21, 2002,
DOY 172(see IGS LOGS for details). On July 3, DOY 184, the station resumed
operation using an Ashtech Z-X113T. The rebuilt AMC2 station now serves as
both an IGS station and as the source for calibrated UTC time for the JPL
Global Real Time Differential GPS network. All pseudo-range data are
adjusted during the data collection process to account for all timing
calibration biases, and thus any clock solution referenced to this station
will be calibrated with respect to UTC with an accuracy of a few ns.
 
Also on June 14, 2002, DOY 165 the AMC2 AOA/M_T Antenna was replaced with
another AOA/M_T Antenna using improved antenna electronics, which better
support absolute time calibration.
 
Ed Powers
USNO
(202)762-1451
powers.edward@usno.navy.mil