Hello Time-Nuts, I can attest that GPS works fine at the poles, though my experience was at the South Pole. Every year the USGS goes to the South Pole to mark the geographic pole. Since the ice is moving 10 meters per year at the pole the pole appears to march across the ice. One year ('97-'98 I believe) I took my GPS II and sat it on the choke ring antenna the USGS had set up. It read S89°59'59" latitude. I was impressed! We waited a bit to see if it would ever read 90° but it did not. It just wandered around a bit. My speculation is that the math blows up at 90° so it never goes there. I have a picture of the event as well. If I get some time this evening I'll have to scan it and post. Yes, I agree that the HDOP is better at the poles and the VDOP worse, but GPS works perfectly well anywhere on earth (for most purposes). Regards, Skip Withrow

I have been watching the thread and there is no reason for GPS not to work at the poles. Granted there can be solar events that upset it with things like severe multi-path but in general if the skies not glowing its most likely just fine. Also I believe the sats are somewhat low in the sky. Skips comment makes sense on the 90 degrees. I can see how that math would get tricky and its a general use-case that most likely someone said so what.... On the north pole in an aircraft you would most likely rarely ever be exactly at that point and in a plane it would not be all that long. Regards Paul WB8TSL On Tue, Aug 15, 2017 at 3:04 PM, Skip Withrow <skip.withrow@gmail.com> wrote: > Hello Time-Nuts, > > I can attest that GPS works fine at the poles, though my experience was at > the South Pole. Every year the USGS goes to the South Pole to mark the > geographic pole. Since the ice is moving 10 meters per year at the pole > the pole appears to march across the ice. > > One year ('97-'98 I believe) I took my GPS II and sat it on the choke ring > antenna the USGS had set up. It read S89°59'59" latitude. I was > impressed! We waited a bit to see if it would ever read 90° but it did > not. It just wandered around a bit. My speculation is that the math blows > up at 90° so it never goes there. > > I have a picture of the event as well. If I get some time this evening > I'll have to scan it and post. > > Yes, I agree that the HDOP is better at the poles and the VDOP worse, but > GPS works perfectly well anywhere on earth (for most purposes). > > Regards, > Skip Withrow > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. >