Eagle Electronics 12 manual GPS Corrections Datum

last known track direction. When you resume speed, all features operate normally.

When you’re stopped at a traffic light, the track holding feature is useful to prevent the annoying random numbers from appearing on the display while you're stopped. This also prevents the unit from rotating the map in all directions when it's in the "track-up" mode. This feature is useful when you're using the AccuMap 12 while hiking, horseback riding, or other typi- cally slow-speed activities.

To turn the track holding feature off, press the MENU key, then press the up or down arrow keys until the “System Setup” menu appears, then press the right arrow key. The screen shown at right ap- pears. The track holding menu is at the top of this screen. Press the left arrow key to turn the track holding feature off. Press the EXIT key to erase this menu.

GPS CORRECTIONS

DATUM

Maps and charts are based on a survey of the area that’s covered by the map or chart. These surveys are called “Datums”. Maps that are created using different datums will show the same latitude/longitude in slightly different locations.

All datums are named. The GPS system is based on the WGS-84 datum, which covers the entire world. Other datums may also cover the entire world, or just a small portion. By default, the AccuMap 12 shows your position on the map using the WGS-84 datum.

However, it can show your position using one of 99 different datums.

To change the datum, first highlight the “GPS Cor- rections” label on the “System Setup” menu and press the right arrow key. Now highlight the “Se- lect Datum” label. Press the right arrow key. A screen similar to the one at right appears.

The WGS-84 label is highlighted. To change it, simply press the up or down arrow keys until the desired datum is highlighted, then press the ENT key.This selects the datum and erases the datum menu.The AccuMap 12 is now using the datum you selected.

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