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EM-406 Speed wrong?

Tips and questions relating to the GPS modules from SFE

EM-406 Speed wrong?

By paulg24
-  Wed Mar 19, 2008 10:31 pm #45041
My em-406 unit says its travelling anywhere between 0 and 7 knots while it is stationary. This is an error of nearly 10km/h or 6miles/h

Am I doing something wrong here or is this error value normal?

What have been other peoples experience with the speed over ground reading, thanks.

By incognico
-  Wed Apr 02, 2008 4:18 am #45667
With a half decent view of the sky I typically see <1 km/h speed reported when stationary. I've noticed it go up to ~5km/h in poor reception areas (car park buildings etc) but I've never seen much more than that.

Can't say I have paid that much attention though sorry :wink:

There are other ways of measuring speed using the GPS if you're looking for better resolution. eg - http://nujournal.net/HighAccuracySpeed.pdf

By incognico
-  Wed Apr 02, 2008 7:55 pm #45737
Parked in an underground carpark complex today and am seeing up to 17km/h reported. Must be some freaky reflections going on :)

SiRF III constantly amazes me where it will manage to get a signal at all.
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