GPS possition was several nm vrong
 

The 1. jan 2004 around 18.30 UTC, the clock in one of the
GPS-satellites had a malfunction. This resulted in a distance-fault
from this satellite of up to 285 km (normally under 10 meter).

A fault like that is not serious if it is spotted immediately, and the
satellite is put out of play, so it isn't used in the position
calculation.
In this case the fault wasn't spotted by the GPS-earth-station until 3
hours later. Then the satellite were labelled "unhealthy" so it would
be left out of the calculations.

For 3 hours GPS receivers calculated faulty positions up to several nm
out of place.

Published 30. jun 2004: http://www.frv.dk/ifm/navigation/gps.htm
This link is better: http://www.frv.dk/nyheder/nyheder.htm#54

This illustrates the limitations of this in many ways wonderful and
cheap device.


Peter S/Y Anicula

Possition is wrong, and so is vrong.

Why doesn't my spellchecker check the subject line ?

Peter S/Y Anicula


"Peter S/Y Anicula" skrev i en
meddelelse ...
The 1. jan 2004 around 18.30 UTC, the clock in one of the
GPS-satellites had a malfunction. This resulted in a distance-fault
from this satellite of up to 285 km (normally under 10 meter).

A fault like that is not serious if it is spotted immediately, and
the
satellite is put out of play, so it isn't used in the position
calculation.
In this case the fault wasn't spotted by the GPS-earth-station until
3
hours later. Then the satellite were labelled "unhealthy" so it
would
be left out of the calculations.

For 3 hours GPS receivers calculated faulty positions up to several
nm
out of place.

Published 30. jun 2004: http://www.frv.dk/ifm/navigation/gps.htm
This link is better: http://www.frv.dk/nyheder/nyheder.htm#54

This illustrates the limitations of this in many ways wonderful and
cheap device.


Peter S/Y Anicula

So you mean Bobsprit could be sailing in what he thinks is LIS and actually
be in Toledo? Kewl!

M.

Peter S/Y Anicula


"Peter S/Y Anicula" skrev i en
meddelelse ...
The 1. jan 2004 around 18.30 UTC, the clock in one of the
GPS-satellites had a malfunction. This resulted in a distance-fault
from this satellite of up to 285 km (normally under 10 meter).

A fault like that is not serious if it is spotted immediately, and
the
satellite is put out of play, so it isn't used in the position
calculation.
In this case the fault wasn't spotted by the GPS-earth-station until
3
hours later. Then the satellite were labelled "unhealthy" so it
would
be left out of the calculations.

For 3 hours GPS receivers calculated faulty positions up to several
nm
out of place.

Published 30. jun 2004: http://www.frv.dk/ifm/navigation/gps.htm
This link is better: http://www.frv.dk/nyheder/nyheder.htm#54

This illustrates the limitations of this in many ways wonderful and
cheap device.


Peter S/Y Anicula

I think the actual position fault was less than that, but in Bobsprits
case - who knows ?

Peter S/Y Anicula

"Michael" skrev i en meddelelse
...
So you mean Bobsprit could be sailing in what he thinks is LIS and
actually
be in Toledo? Kewl!

M.

Peter S/Y Anicula


"Peter S/Y Anicula" skrev i en
meddelelse ...
The 1. jan 2004 around 18.30 UTC, the clock in one of the
GPS-satellites had a malfunction. This resulted in a
distance-fault
from this satellite of up to 285 km (normally under 10 meter).

A fault like that is not serious if it is spotted immediately,
and
the
satellite is put out of play, so it isn't used in the position
calculation.
In this case the fault wasn't spotted by the GPS-earth-station
until
3
hours later. Then the satellite were labelled "unhealthy" so it
would
be left out of the calculations.

For 3 hours GPS receivers calculated faulty positions up to
several
nm
out of place.

Published 30. jun 2004: http://www.frv.dk/ifm/navigation/gps.htm
This link is better: http://www.frv.dk/nyheder/nyheder.htm#54

This illustrates the limitations of this in many ways wonderful
and
cheap device.


Peter S/Y Anicula

No wonder Jax can't find the Gulf Stream!

Ole Thom

Funny you should mention Toledo, sailing on Lake Erie last week in the
vicinity of several power plants I noticed my gps acting up, wondering if
they have the ability to mess with the signal in certain areas? Or maybe
it's just my ageing free Cadillac gps?
John Cairns
----- Original Message -----
From: "Michael"
Newsgroups: alt.sailing.asa
Sent: Sunday, August 15, 2004 2:10 PM
Subject: GPS possition was several nm vrong


So you mean Bobsprit could be sailing in what he thinks is LIS and
actually
be in Toledo? Kewl!

M.

Peter S/Y Anicula


"Peter S/Y Anicula" skrev i en
meddelelse ...
The 1. jan 2004 around 18.30 UTC, the clock in one of the
GPS-satellites had a malfunction. This resulted in a distance-fault
from this satellite of up to 285 km (normally under 10 meter).

A fault like that is not serious if it is spotted immediately, and
the
satellite is put out of play, so it isn't used in the position
calculation.
In this case the fault wasn't spotted by the GPS-earth-station until
3
hours later. Then the satellite were labelled "unhealthy" so it
would
be left out of the calculations.

For 3 hours GPS receivers calculated faulty positions up to several
nm
out of place.

Published 30. jun 2004: http://www.frv.dk/ifm/navigation/gps.htm
This link is better: http://www.frv.dk/nyheder/nyheder.htm#54

This illustrates the limitations of this in many ways wonderful and
cheap device.


Peter S/Y Anicula

"John Cairns" wrote in message
m...
Funny you should mention Toledo, sailing on Lake Erie last week in
the
vicinity of several power plants I noticed my gps acting up,
wondering if
they have the ability to mess with the signal in certain areas? Or
maybe
it's just my ageing free Cadillac gps?

Mine still works fine, though I barely use it.

Scotty

"Michael" wrote in message ...
So you mean Bobsprit could be sailing in what he thinks is LIS and actually
be in Toledo? Kewl!

M.


Hey Michael,

Saw the ship you were talking about named after my sailboat!
Thats one big MF. Fairly new as well. Looks like it could carry a
whole bunch of stuff

Joe



Peter S/Y Anicula


"Peter S/Y Anicula" skrev i en
meddelelse ...
The 1. jan 2004 around 18.30 UTC, the clock in one of the
GPS-satellites had a malfunction. This resulted in a distance-fault
from this satellite of up to 285 km (normally under 10 meter).

A fault like that is not serious if it is spotted immediately, and
the
satellite is put out of play, so it isn't used in the position
calculation.
In this case the fault wasn't spotted by the GPS-earth-station until
3
hours later. Then the satellite were labelled "unhealthy" so it
would
be left out of the calculations.

For 3 hours GPS receivers calculated faulty positions up to several
nm
out of place.

Published 30. jun 2004: http://www.frv.dk/ifm/navigation/gps.htm
This link is better: http://www.frv.dk/nyheder/nyheder.htm#54

This illustrates the limitations of this in many ways wonderful and
cheap device.


Peter S/Y Anicula

You are never VRONG!

I just found out that there are english versions of the pages I linked
to:

http://www.frv.dk/en/nyheder/nyheder.htm#54
http://www.frv.dk/en/ifm/navigation/gps.htm

"Peter S/Y Anicula" skrev i en
meddelelse ...
The 1. jan 2004 around 18.30 UTC, the clock in one of the
GPS-satellites had a malfunction. This resulted in a distance-fault
from this satellite of up to 285 km (normally under 10 meter).

A fault like that is not serious if it is spotted immediately, and
the
satellite is put out of play, so it isn't used in the position
calculation.
In this case the fault wasn't spotted by the GPS-earth-station until
3
hours later. Then the satellite were labelled "unhealthy" so it
would
be left out of the calculations.

For 3 hours GPS receivers calculated faulty positions up to several
nm
out of place.

Published 30. jun 2004: http://www.frv.dk/ifm/navigation/gps.htm
This link is better: http://www.frv.dk/nyheder/nyheder.htm#54

This illustrates the limitations of this in many ways wonderful and
cheap device.


Peter S/Y Anicula