Accuracy plots of garmin gpsmap 62 st?

Long time no see....

After using my trusted Meridian platinum for about 6 or 7 years it is time
to update. I might consider the garmin gpsmap 62 st, but only if it is more
accurate. Using official Dutch benchmarks my Meridian never was off by more
than 3 meters using EGNOS. (I can repeat my tests again and again and they
are consistant) The garmin gpsmap 62 st has to equal that or do better if I
want to buy it.

I'm looking for measured (not claimed by garmin) accuracy data of the garmin
gpsmap 62 st. SA Watch or Visual GPS plots would be fine.

I have googled for hours but have found nothing... at... all.

Even gpsinformation.net (which has a nice article about this gpsr) does not
mention anything about accuracy. Nice story about the menu's etc. but no
measurements.

Hmm, am I missing something here? The whole point of a gpsr is to pinpoint
position as accurately as possible? Or am I being naive?

Anyway: does anybody have accuracy measurements/tests of the garmin gpsmap
62 st? Help would be greatly appreciated!

TIA, Vincent

On 2011-06-27 17:58 , Vincent van der Laan wrote:

I can assure that your GPS is only as accurate as local conditions. I
too can get 2 - 3 meter SBAS (WAAS) benchmarks if the sky is clear of
trees and other obstructions....

But leave my GPS in a forested area and let it record for 10 minutes and
the walk can cover 50 meters radius.


Reception conditions can have a great effect on accuracy. Don't assume
when walking in the woods, or on a trail on the side of the mountain, or
in the urban canyons of the city that you are getting the same accuracy
as at a "clear sky view" benchmark.


--
gmail originated posts filtered due to spam.

Which GPS receiver do you have?

I have been using GPS for 10 years now (and have read all articles from sam
Wormley about multipath, VDOP, HDOP, error sources etc.) so I totally agree!

I would like information on multipath handling as well.
And also: does the garmin do auto averaging when standing still?

I can't find any accuracy related technical specs.
Not even on Garmin's website.

Cheers, Vincent

On Tue, 28 Jun 2011 11:01:06 +0200, Vincent van der Laan wrote:
        [....]

        This may be urban legend, and if not probably requires
installations with a l-o-o-o-n-n-gg *fixed* baseline (originally between
MIT and CalTech iirc; and before geostationary satellites, I think, so
they may have had a third point on the Moon) -- but fwiw the technology
seems to've developed out of an experiment designed to allow measuring
continental drift. In inches per century. That's with the sky the limit
on cost, weight, everything else, of course; but afaik they did measure
it.

        It's plausible insofar as NASA once boasted an ability to aim a
beam from Houston into a coffee cup on the Moon. And triangulation is an



--
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What do they know of country, who only country know?

I
me
r
am
ee!

On every Garmin I own, you have to select averaging. If you dig
through old posts on this group, averaging itself isn't as good as you
think. Now most of these GPSs will do some weighted average of the
satellites that they can see, based on SNRm but that is not like
averaging readings.

To measure accuracy, you really need to find a landmark that has been
measured accurately.

http://www.ngs.noaa.gov/cgi-bin/ds_mm.prl

It has been my experience that a great deal of these landmarks are not
exactly easy to access. Some are in the middle of the street! The
spots that can be seen from satellite are my choice. You can look at
them on google earth to determine access. You also want to make sure
you can linger on the spot if you want to do averaging. On my
gps60csx, using English units, I get readings good to 4ft with
averaging. Not spectacular, though it is sub-meter.

The satellite visible landmarks show up as a big X. Those google earth
bastards trespassed on some undeveloped land I own and set up a
landmark. [Yeah, I was surprised to see a big X show up on google
earth on my property.] The lines of the X appear to be north-south and
east-west. Anyway, if you see an X on google earth, it may not be a
permanent marking. The ones in the USGS database are painted, but the
survey points used by google earth are done with some sort of
biodegradable sheeting. Not as flimsy as paper, but it does decay.