Dynon 180 compass calibration

[jamespearce]

After a black screen status last year, Dynon repaired my 180 but it failed again within a month. It went back to Dynon and was repaired again under warranty. I'm in the UK but the turnaround was very efficient. All seems well now and after recalibrating the compass on its last return (about 6 months ago), following the Dynon method to the letter, the indicator subsequently has become as much as 30 degrees in error despite being set within 1 or 2 degrees at the time. I wonder if their are any major heads up points I should be aware of?
I have just run a recalibration today. What is interesting is that after a first calibration run, there were errors of 5 or 6 degrees when rechecked on its cardinal points. A second run has left it, for the time being, accurate to a degree. Might I expect an increasing accuracy with the number of recalibration runs? This is still a great device and my flight safety has been enhanced with its continued use in my Foxbat in some, occasionally, marginal VFR flying in the UK. Thanks Dynon.

 

[Dynon]

Each calibration is completely independent. It won't get better with more. Where are you in the world? And what values did you put in for the magnetic model numbers before you calibrated? Where is your EDC-D10A in the aircraft? Is it well away from any ferrous metal and power?

 

[jamespearce]

Thanks for your reply. I am in the south of England UK and I have attached the data I used prior to the compass calibration. I used 66 degrees for the inclination and 48,593 nT for the Total Field figures. The EDC- D10A is on the floor in the back of the aircraft, behind the seats and clear of any possible magnetic sources and wiring. I'll check it more often to ensure it remains accurate. Cheers, James.

 

[Dynon]

You got the numbers right (people commonly use the declination, mistakenly, since it's charted).