Random lines in GPS data

[David Ferguson]

I have seen large "position deltas" that result is wide-ranging random lines in a track map view. Sometimes this is caused by logging before the GPS lock has been obtained, and in one case it was a bad mounting location that obscured the antennas view of the sky.

However, sometimes it just seems to be random.

Any ideas on the best way to isolate the cause of the "deviations". Have any issue related to this been addressed in any of the firmware updates?

David Ferguson
Veracity Racing Data

[ewaher]

When I have this problem it is usually caused by not allowing enough time for the logger to lock onto several satellites. I am running behind and just hop in the car and drive. Usually those runs require me to cut out the first few seconds of data to remove.

Out of 50 or so days that I've used the logger this has happened to me maybe 4 or 5 times. Usually before I start driving that day just pop the ignition on an leave the logger running for 10 minutes, after that I turn it on and it acquires quickly. Rarely do I have a problem with this process.

I would try testing for what causes the problem. For starters, I would try to turn the logger on and start driving quickly, or cover the antenna up, restrict how many satallites the logger can pickup and see what happens to the data.