Delivered-To: igsmail@igscb.jpl.nasa.gov
Message-ID: <20E81FA1A1DD404F87AC7DE3E01E28A5029463E3@mlts1.lt.admin.ch>
From: elmar.brockmann@swisstopo.ch
To: igsmail@igscb.jpl.nasa.gov
Subject: [IGSMAIL-5191]: ZIMZ: permanent operation discontinued on
  Aug.17, 2005
Date: Thu, 18 Aug 2005 16:37:04 +0200
Content-Type: text/plain
Sender: owner-igsmail
Precedence: bulk

******************************************************************************
IGS Electronic Mail      18 Aug 07:37:11 PDT 2005      Message Number 5191
******************************************************************************

Author: E. Brockmann

On August 17, 2005, 07:00 UTC, the Ashtech Z18 receiver ZIMZ was put out of
operation. During the last months, the receiver/firmware seemed to suffer
more and more from symptoms of old age. Receivers resets were necessary
every 3-7 days.

ZIMZ was in operation since September 3, 1998, permanently delivering data
to IGS and IGLOS. The available tracking data was always of high quality.
Only the circumstance that this receiver model generation is unable to
sample active GPS/GLONASS satellites which are marked unusable may be
considered as a deficiency. 

The GPS/GLONASS-combined TPS receiver ZIMJ continues operation. ZIMJ belongs
to a group of about 18-19 receivers sampling the complete active GNSS
satellite constellation (currently consisting of 29 GPS plus 13 GLONASS),
independent of whether a satellite is marked unusable, or unhealthy, or even
is being repositioned.

We apologize for any inconveniences this may cause.

Kind regards
The teams of AIUB and swisstopo


swisstopo
Federal Office of Topography
Geodesy
Seftigenstrasse 264
CH-3084 Wabern
Phone	+41 31 963 21 11	operator
	+41 31 963 22 56	direct
Fax	+41 31 963 24 59
elmar.brockmann@swisstopo.ch
www.swisstopo.ch