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3.3.5. Reference altitude and barometric pressure
To ensure that the altimeter shows correct readings, you first need to set an accurate reference altitude. To do this, go to a location whose altitude you have checked, for example, with the help of a topographical map, and set the reference altitude to match the map reading.
NOTE: If you do not know the current altitude, go to the Position display and check the altitude with the GPS. The longer the GPS is on, the more accurate the altitude reading will be.
If you do not have accurate altitude information, you can use the current
Setting the reference altitude
To set the reference altitude:
1.In the Set menu, Reference is the first menu item. Press ENTER to select it. The reference menu opens.
2. Altitude is the first menu item. Press ENTER to select it. The Altitude display opens. The previously set altitude is highlighted.
3.Change the altitude with UP/DOWN and press ENTER. The reference altitude is now set and you return to the
Reference menu.
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