Revision A9 27
GRT Avionics Mini-X Installation, Setup & User Manual
4.5 External Magnetometer Location Validation
Skip to Section 4.8, Altimeter Calibration, if you do not have the optional external remote
magnetometer. The internal magnetometer cannot be calibrated.
NOTE:
When the magnetometer wiring is connected to the designated magnetometer connection
pins on the DB15 connector, the Mini will automatically detect it upon boot-up and set up or
verify the magnetometer serial port settings.
Verify the PFD screen shows HDG next to the heading box at the top-center of the screen. This
indicates that it is receiving valid heading data from the magnetometer.
1. Park the aircraft on a level surface and start the engine.
2. Perform the steps in section
4.6 Set Final Magnetometer and Instrument Orientation
3. Access Set Menu > AHRS Maintenance. Locate
Magnetometer Heading
field on this screen.
NOTE:
Do not use the heading data shown on the heading tape on the PFD for calibration
because this is a composite reading of several other pieces of information. The Magnetic
Heading field contains instantaneous data on magnetic heading only.
4. Observe the Magnetic Heading and verify it does not change by more than +/- 2 degrees
while doing the following:
a. Turn on and off any electrical equipment whose wiring passes within 2 feet of the
magnetometer.
b. Move all flight controls from limit to limit.
c. Shut down the engine and observe the heading while the engine is not running.
d. For aircraft with retractable landing gear: If the magnetometer is located within 2 feet of
retractable landing gear, support the aircraft using proper jacking equipment, then observe
the heading while operating the landing gear.
e. If greater than +/- 2 degree change is noted, either relocate the magnetometer or the
offending wiring or metallic materials. Recheck. If there is any doubt about a location, try
moving the magnetometer to another location. Use tape or other temporary means to
hold it in place and repeat the test.
5. While the calibration procedure can remove errors as large as 127 degrees, accuracy is
improved if the location chosen for the magnetometer requires corrections of less than 30
degrees. To check the uncorrected heading error:
a. Go to Set Menu > AHRS Maintenance > Magnetometer Calibration.
