Garmin 101 Owner's Manual

48

A map datum is a reference model of the earth’s shape.  Every map uses a map datum 

which is usually listed in the title block of the map.  The default datum in the Foretrex 101 
is WGS 84 (World Geodetic Survey, 1984).  You should only change the datum if you are 
using maps or charts that specify a different datum.  Choose the ‘USER’ datum if using a 
map with custom-designed grids.  

The ‘USER’ datum is based on a WGS-84-Local datum and is an advanced 

feature for unlisted or custom datums.  To learn more, check your local library or 
the Internet for educational materials on datums and coordinate systems.

1.  Press the 

button until the Main Menu Page is displayed.  Use the 

and 

buttons to highlight ‘SETUP’ and press 

.

2.  Use the 

and 

buttons to highlight ‘SET UNITS’ and press 

3.  Press the 

 or 

 button to highlight the ‘MAP DATUM’ field and press the 

 button.

4.  Press the 

 or 

 button to highlight the desired datum and press the 

 

button.

5.  Press the 

 button to return to the Main Menu Page.