I can get a GPS fix, and my loiter mode operates fine, but I get zero satellites or HDOP in Mission Planner and logs.

I have a Ublox LEA-6H GPS and an APM 2.8. As the title says, I cannot see HDOP or the number of satellites despite there being a sufficient GPS lock for Loiter Mode. In the logs, I can see my latitude and longitude, and most other relevant info, but not the sat count or HDOP.

This may be an unrelated problem, but I cannot see the correct time in my logs either. I vaguely remember reading somewhere that the APM does not have a real-time clock on board, and gets time info from the GPS. All my logs report that the date/time is sometime in 1970. I say that it may be unrelated because I see some other issues online where people got weird log dates when their GPS was otherwise behaving normally. So I think it's possible that I'm suffering from the same (simultaneous) problems.


Some background - I got this GPS unit from a friend, who had changed and updated the on-board settings to be used with a different non-drone project. He changed, among other things, the baud rate and the NMEA/UBX messages being sent. At first it wouldn't work with my system, so used uCenter to re-flash the unit with the config file I found in the Arducopter github repository. Now it is recognized by my APM, and can fly just fine - but doesn't report the info mentioned. I would have thought that flashing the GPS with the config file would correct any deviant settings? How is it that most are fixed but some are not?

I have attached an example log. Please ignore the flight mode error and radio failsafe - I was testing a number of features, including the failsafes. Also, apparently I tried to enter auto mode with no flight path saved. As you can see, however, GPS status = 3 (3D fix), however the NSat or HDOP values are zero.

Any ideas?

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