It shows I'm driving off the road ! Nuvi 350

It is alleged that ak.kesler@verizon.net claimed:


If they were doing anything that could interfere with the reception of
the satellite signals, it could easily have caused the problem. A
thunderstorm could conceivably throw it off.

--
Jeffrey Kaplan www.gordol.org
The from userid is killfiled Send personal mail to gordol

"You wanted to kill me from the start." "Ah, screw you, Maybourne. I
was joking. Look what you did to my leg." "I set the trap for the
pig." "With a grenade?" - Harry Maybourne and Jack O'Neill, SG1

It could have been a temporary error from a single satellite which is why it
fixed itself after a while as other satellites came in to range. Other
sources of errors:

Ionosphere 0-30 meters
Troposphere 0-30 meters
Measurement Noise 0-10 meters
Ephemeris Data 1-5 meters
Clock Drift 0-1.5 meters
Multipath 0-1 meter

http://www.cmtinc.com/gpsbook/index.htm

Bruce.

If the error only occurs after you make a U-turn or other turning maneuver,
then the error might be caused by loss of signal from some of the
satellites. The accuracy of the GPS improves with the number of satellite
contacts/time.
A recurring error in the same location may be that the maps stored in the
unit are off. The nuvi 350 I have shows my address as being about 5 houses
South of the actual location, and my Delorme GPS shows my address as being a
hundred yards NW of me.

I may be wrong about this, but I don't the maps have lattitude/longitude for
individial street address. Rather the GPS guesses based on estimating that,
for example, 2250 should be somewhere near the middle of the 2200 block.

Different GPSs might make different guesses.

Bruce.

This morning I went back over the place that first was off, made the same
turn, and it followed OK.