[OSM-talk] Garmin eTrex Vista Hcx

[Jon Burgess]

On Sat, 2009-10-31 at 21:45 +0000, Randy wrote:
> 
> These are more likely the reason for the issue Shalabh described. The 
> position has been frozen at an inaccurate point, and when the GPS
> power is 
> cycled, it comes back up with a good lock and resets the position
> based on 
> the new measurement. I would doubt an "error buildup" just because
> GPS 
> fixes are based on discrete fixes, rather than any kind of
> incremental 
> measurements.

I have a trace which fits the profile of an accumulated error. The
attached screenshot shows several NaviGPS traces in JOSM for the section
of motorway around the M25, M3 junction. One trace is clearly offset by
up to 300m for a significant period of time.

http://www.openstreetmap.org/?lat=51.40094&lon=-0.53633&zoom=15&layers=B000FTF

	Jon


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