Garmin GPSMAP 60Cx Manuale Utente

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PPENDIX

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Map Datums are based on a 

mathematical model of the Earth.

A datum is a mathematical model of the Earth that 

approximates the shape of the Earth, and enables 

calculations to be carried out in a consistent and 

accurate manner. The datum is physically represented 

by a framework of ground monuments whose 

positions have been accurately measured and 

calculated on this reference surface. Lines of latitude 

and longitude on a map or chart are referenced to a 

specific map datum. Every chart has a map datum 

reference and the GPSMAP 60Cx can be set to match 

most of those commonly used.
If you are navigating and comparing the GPS 

coordinates to a map, chart, or other reference, set the 

map datum in the GPS unit to the same datum as the 

map to insure the most accurate navigation.

Your current location can be viewed on the GPS in the 

form of coordinates. Since different maps and charts 

use different location formats, Garmin GPS units 

allow you to choose the correct coordinate system 

for the type of map you are using. The most common 

format is latitude and longitude, which is used by all 

Garmin units. 
You can choose to change the location format to use 

with other coordinate systems. UTM/UPS (Universal 

Transverse Mercator/Universal Polar Stereographic) 

are easy-to-use metric grids that are found on most 

USGS topographic quadrangle maps. You can also 

select one of several other grids, including a user-

definable grid (for the advanced user).