I know, I know, the old GPS is garbage. That being said, it does function. Yesterday I turned mine on, mostly for keeping the time/speed/distance calculation accurate to get to an appointment 100 miles away. Anyway, weather was both raining, overcast, then sunny and clear, and it would not connect to the satellite constellation. I believe the map disc is fine, as it would show the location on the map for the destination, but could not identify where the car was located in order to perform the calculation. Any ideas or theories on what's going on here? I did not find any notice from the US gov. on GPS outages, but I suppose anything is possible. Thoughts?

 

Well, five days later the GPS started picking up the satellites again, and a day after that figured out the correct location of the car...I'm going to go with 'solar flares'...or something...

 

You raise a good question - how many channel GPS does the AM use? More the merrier and the more robust it's ability to geolocate.

Here's an interesting site and some comments on Geomagnetic activity (related to solar activity) and GPS: https://www.swpc.noaa.gov/impacts/sp...nd-gps-systems

We should all thank Roger Easton and Martin Votaw - the guys at the Naval Research Laboratory who patented and invented GPS. They lived long enough to see the commercial and civilian use of what they thought would only be used by US Naval forces at sea...

 

I used to live across the river from NRL and sail / row past it regularly on the Potomac in high school.

I believe the Aston / Volvo / Ford hobgoblin system uses 6 satellites when it is optimally functional. I had "other suspicions" about why civilian GPS wasn't working for a week, but I couldn't find any other complaints during the time period, so I'm chalking it up to space weather. I was in at least a dozen locations over the week attempting to connect, from moderately treed areas to very open parking lots, so I don't think it was overhead cover interfering. Weather was from overcast, to clear, to thunderstorms, too many variables to pin it on that. I suppose it could also be some sort of intermittent connection failure for the antenna but that doesn't explain why it would not load the previous map location etc. from the the main drive. Mysterious.