Dynon's remote compass module permits magnetic heading to be sensed in an area of the aircraft where magnetic interference is minimal. Positioning is critical, so the instructions in the installation guide should be closely adhered to. Following calibration, the remote compass will yield excellent results with an accuracy of just a couple degrees.
The remote compass is available as an option for the EFIS-D10A, which has a set of internal magnetic sensors.
The EFIS-D6, EFIS-D60, and EFIS-D100 and the FlightDEK-D180 come with the remote compass module standard.