Originally Posted by Lord Raiden

Well, since a corrupt nvd_data is believed to be part of the problem, does anyone have either a way to reset nvd_data to default values, or a clean one I can start again with?

EDIT: AHA! I did some digging and found someone who had actually tried deleting the nvd_data file (I simply renamed it nvd_data.old) and told GPS to start fresh. I tried that and, believe it or not, it got a GPS fix in less than a minute!

Originally Posted by Paxton

I don't know if this is old news or not, but I thought I'd post anway.

I had two N810s that refused to fix (>12 hours) and were sitting on the same window sill as two others that were happily locked on. The two sick ones couldn't see any satellites whilst the other two could see seven or eight with at least four lit up in green.

I found that I could copy the /var/lib/gps/nvd_data from one of the good ones to the two ailing ones, restart the gpsd (via the GPS Enable tick box) and they both recovered.

There is now a script sitting on all four that, should I get stuck again, will copy a 'good' nvd_data to /var/lib/gps. Hopefully this will allow me to get working again if the problem reappears (which it will).

My guess is that, if gpsd shuts down when it is not locked, then garbage can get written to nvd_data. Sometimes it can cope, other times it can't and the effects are unpredictable.

I imagine that, for this workaround to be of use to anyone else, you would need your own 'good' nvd_data saved at a time when you know it is locked on in your part of the world.

HTH

Paxton

P.S. I've tried copying the nvd_data to a fifth N810. My window sill isn't big enough for that one, so it is on a bench well away from the window. It has locked on no problem.