Magellan NAV 5000, Руководство пользователя

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Use the RIGHT ARROW to
scroll through the available
datums until you find one
that corresponds to your
chart. Press ENTER.
Selecting a Map Datum
The NAV 5000 provides 12 geodetic map datums for use with charts
and maps worldwide. The unit also allows you to enter manually
any map datum not currently in the unit's memory.
A datum refers to a mathematical model of the earth. The latitude and
longitude of a position differs from one model (datum) to another. lt is
therefore important to know which map datum you will be using if you
want to relate your position information to a chart, since using a
different datum may result in positioning errors of up to 1968.5 feet
(600 meters) when compared with the chart.
The Map Datum feature allows you to operate the NAV 5000 on a
datum that corresponds to the charts you are using. Which datum your
chart uses can usually be found in the legend.
From the Lat/Lon display,
press the DOWN ARROW.