Explanation for weird GPS tracks last week

[nowster]

dcrainmaker.com/2022/07/gps...

Apparently, duff satellite ephemeris data was being supplied to watches with GPS receiver chips made by Sony. This includes most Garmin watches made in the last four years.

The symptoms were that your GPS track would be consistently off in one direction for part of the track, then become more accurate the longer the session lasted.

It's said to be fixed now.

[Kirst13 Graduate10]

That explains why my slow jog alongside my walking daughter registered as a very fast run for me- the mapped route had lots of wobbles in it. Thanks for sharing.

[nowster Graduate10 in reply to Kirst13]

It probably wouldn't cause wobbles, but would cause the start of a track to be shifted in one direction by about half a mile. Wobbles are more likely to be caused by tree cover or tall buildings.

[Kirst13 Graduate10 in reply to nowster]

Realised afterwards that I had actually tracked that one on the phone 🤣but I have had to crop quite a few starts that were not where I started. I had just put it down to my impatience and nor waiting for GPS signal.

[Cmoi Graduate10]

Thanks nowster , interesting reading.