[at-l] Handheld GPS accuracy

[rockdancer97 at comcast.net]

On the topic of handheld GPS accuracy: is there a spec-sheet performance number I can use to compare units or is there a website with "tried in the field" actual ratings for handhelds? I've used a few borrowed items and would like now to get one for myself. Recommendations gratefully appreciated. --RockDancer

Arthur Gaudet
Lowell, MA
Rockdancer97 at comcast.net
"The vessel with the pestle has the brew that is true."

I showed him the GPS
> 
> that I was using to gather data with. It was absolutely the best
> 
> hand-held mapping GPS available at the time. So is my current one, but
> 
> it is not the same one.
> 
> 
> 
> Anyway, the GPS had been sitting still for 10 minutes or so, making a
> 
> fixed waypoint, and the satellite pattern was especially good that
> 
> day. The expected Horizontal error was around 5 feet. Vertical is
> 
> always about double the horizontal. The GPS disagreed with the GATC on
> 
> elevation by about 30 feet at that shelter, as it did most of the way
> 
> through Georgia. It turned out that when Del Doc had gathered data in
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> the area in '02, there was a problem with the antenna that he was
> 
> using. When the cartographer went to re-do the maps, he had to use the
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> old 80s-vintage Topos as overlays in his GIS to guess at a lot of the
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> elevations and shelter locations. When they later re-gathered the data
> 
> with a newer, better GPS, the companion and my GPS started magically
> 
> agreeing, or at least being very close.