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APM 2.5 compass calibration


Senior Member
Hi all,

For future projects I've got an APM 2.5, with internal compass and external GPS (the Mtek one, flashed to v1.9 firmware).

I just did a (living room) Compass calibration dance, well several to be precise.....
But the calibration results vary a lot (and I really mean a lot) ..

I roughly know where the North is and I also know an iPhone 5 Compass is not too accurate, but when calibrating the APM 2.5, I see deviations between 10 degrees up to 80 degrees (!) difference (at that point I could tell it was not the iPhone that was way off).

Are there any other APM 2.5 users that experience the same?

Is there an -apparently secret- way to perform the "Calibration dance" ? :)

I now think I should have left it where it was only a few degrees off..

PS, there is the auto inclination setting, but it differs from when I actually look up the inclination for my location.
Any ideas on that?

PS: I kept clear of metal and other obvious magnetically interference (Including the phone etc)
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Amateur Extra Class K5TWM
The compass is VERY sensitive. Any magnetic sources will have an effect on your "dance" results. I have too many BIG neo's in my house (home brew wind turbine builder) so my dances take place outside where the flying will occur. I always use the looked up declination settings on mine (APM 2 and Arduflyer 2.5)



Senior Member
Thanks Thurmond,

I'll keep that in mind !

Next 'Dance' will occur outside (at a time the neighbors will be indoors for dinner I hope:), well give the autumn-like weather these days in the Netherlands that should not be a problem, then again flying is ...