From:
"Pierre Cao" <pierre.cao@ib.be>
Sent: 1/24/2001 8:06:46 AM
To:
gpsstash@egroups.com
Cc:
Bcc:
Subject:

Re: [gpsstash] averaging a GPS position


See the David L. Wilson's GPS Accuracy Web Page
http://users.erols.com/dlwilson/gps.htm

The "returning to a position" page describes the error we can expect when
hunting for a stash. Some figures show that "only a small advantage is
achieved by averaging the initial visit for a period up to an hour".
http://users.erols.com/dlwilson/gpswaypt.htm

Pierre

----- Original Message -----
From: "Mike Teague"
To:
Sent: Wednesday, January 24, 2001 3:06 AM
Subject: Re: [gpsstash] averaging a GPS position


> EPE will reduce with averaging... try the exact same location about once
> every 2 or 3 days for a month.... that will give you real accuracy...
>
> it's only accurate if it's repeatable.. without SA, the main culprit is
the
> ionospheric delay... and it can be something like a 10 meter error ...
so...
>
>
>
>
>
>
>
>
>
>
> Mike Teague - http://www.triax.com/yngwie
>
>
>
> ----- Original Message -----
> From: "Richard Amirault"
> To:
> Sent: Tuesday, January 23, 2001 4:11 PM
> Subject: Re: [gpsstash] averaging a GPS position
>
>
> > I think the main use for "averaging" was for when Selective Availability
> > (SA) was turned on and activly degrading our accuracy.
> >
> > Since this has been turned off, and our 'civilian' GPS's units are more
> > accurate than before, the 'averaging' feature in our GPS units is pretty
> > much useless. (BUT .. they *could* turn SA back on at *any* time ... if
> they
> > wanted to )
> >
> > Richard Amirault N1JDU
> Boston,
> > MA, USA
> > www.erols.com/ramirault "Go Fly A Kite"
> > ----- Original Message -----
> > From:
> > Subject: [gpsstash] averaging a GPS position
> >
> >
> > > Not wanting to be controversial, but I believe the averaging people
> > > talk about doing when recording the lat/long of a cache is of little
> > > use unless the averaging is for a long time, like 24hrs.
> > (snip)
> >
> >
> > The gpsstash page
> > http://www.geocaching.com
> > The GPS Stash Hunt page.
> > http://www.triax.com/~yngwie/gps.html
> >
> > GeoCache HQ
> > http://www.braveheart.com.au
> > GPS Stash Hunt FAQ :
> > http://www.triax.com/~yngwie/stashfaq.txt
> > To unsubscribe from this group, send an email to:
> > gpsstash-unsubscribe@egroups.com
> >
> >
>
>
> The gpsstash page
> http://www.geocaching.com
> The GPS Stash Hunt page.
> http://www.triax.com/~yngwie/gps.html
>
> GeoCache HQ
> http://www.braveheart.com.au
> GPS Stash Hunt FAQ :
> http://www.triax.com/~yngwie/stashfaq.txt
> To unsubscribe from this group, send an email to:
> gpsstash-unsubscribe@egroups.com
>
>
>
>