Subject: [IGSMAIL-0479] Rogue SNR-8, 800, 8C tracking problems during AS
From: Ulf J. Lindqwister/JPL
Date: Fri, 4 Feb 1994 14:47:23 PST

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IGS Electronic Mail      Fri Feb  4 14:47:23 PST 1994      Message Number 0479
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Author: Ulf J. Lindqwister/JPL
Subject: Rogue SNR-8, 800, 8C tracking problems during AS

There appear to be some problems for the big Rogues (SNR-8, 800) and
MiniRogues (SNR-8C) to maintain lock past several hours when AS is
present. We have observed and also received reports of messages
such as 'exceeded P1 phase' in the upload message table for these
receivers in connection with data outages. The information is still
scant and we are performing a series of tests in order to determine
the cause and we are also collecting statistics to try to characterize
the behavior. Early indications point to the
latest firmware release (V7.5), however, several other potential causes are
also suspected and are being investigated. Any additional information
you might have could prove to be helpful - please forward to me by
email or FAX if possible (see addresses below - thanks).

- Ulf

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Ulf J. Lindqwister                 Telephone:   (818) 354 1734
GPS Networks & Operations Group    FAX:         (818) 393 4965
Jet Propulsion Laboratory          Email:       [email-masked]
4800 Oak Grove Dr.
Pasadena, CA 91109
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[Sample of several messages we received on this problem]

> Author: Peter Pesec
> Subject: Problems with SNR-8C during AS

> A certain time after lockon satellites are rejected with the
> message <exceeded P1 phase> which reduces stored measurement data.
> Termination of the registration process <te> followed by a new
> start <co> solves the problem for some hours. Could anybody
> comment on this problem ?

> Peter,Graz,Austria