Garmin 496 Manuale Proprietario

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 (such as trig. stations) whose 

locations 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 496 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, the map datum in the GPS unit should 

be set to the same datum as the map to ensure 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 change the location format to use with other 

coordinate systems in Location Preferences. UTM/UPS (Universal 

Transverse Mercator/Universal Polar Stereographic) are easy-to-use 

metric grids that are found on most USGS topographic quadrangle 

maps. Several other grids, including a user-definable grid (for the 

advanced user), are available. 
For more information about using paper maps with your Garmin 

unit, refer to Using a Garmin GPS with Paper Land Maps, available 

for download at 

GPSMAP 496 Owner’s Manual 

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