Garmin eTrex Summit Manuale

44

The default position format (and the one most commonly used) for the eTrex Summit is 

latitude and longitude in degrees and minutes (hdddº mm.mmm). You may also choose from 
17 other position formats. There is also a “User” position format which allows you to approxi-
mate custom-designed grids. For more information on grids and datums we recommend you 
visit the National Imagery and Mapping Agency at 

http://www.nima.mil.

1.  Press the PAGE button and switch to the MENU Page. Press the UP or DOWN button and 

highlight ‘SETUP’. Press ENTER. Press the UP/DOWN buttons to select ‘UNITS’. Press 
ENTER. The UNITS Page appears.

2.  Press the UP or DOWN button to select the ‘POSITION FRMT’ field. Press ENTER.
3.  Press the UP or DOWN button to select the desired format. Press ENTER. Press PAGE to 

get back to the page of your choice.

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

map datum is usually listed in the title block of the map. If you are comparing GPS coordi-
nates to a paper map or other reference, the map datum in the eTrex Summit should match 
the horizontal map datum used to generate the chart or other reference.  

The default datum in the eTrex Summit 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 
than WGS 84. If no datum is specified, you can select each datum applicable to your region 
until you find the datum that provides the best positioning at a known point. You may also 
choose the “User” datum for use with custom-designed grids.  

User 

Datum

User Grid