Calibrating Your Compass - Log into online resource) > Courses > Garmin - Units > eTrex 20x and 30x > Calibrating Your Compass Video
The device has a 3-axis electronic compass (eTrex® 30/30x devices only). You should calibrate the compass after moving long distances, experiencing temperature changes, or changing the batteries.
Go outside, away from objects that influence magnetic fields, such as cars, buildings, or overhead power lines.
From the compass, select menu.
Select Calibrate Compass > Start.
Follow the on-screen instructions.
You can also when logged in view videos for the newer etrex22x & 32x units which you will still find useful for the older model as very similar and there are a lot more training videos for the newer version.
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