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To change the position format, highlight either the
“Position Format” or the “Alternate Format” label
on the “GPS Setup” menu, then press the right
arrow key. A screen similar to the one at right
appears. Press the up or down arrow keys to
select the desired format. Press the EXIT key to
erase the position format menu.
Datum
Maps and charts are based on a survey of the area that’s covered by the
map or chart. These surveys are called “Datums”. Maps that are created
using different datums will show the same latitude/longitude in slightly
different locations.
All datums are named. The GPS system is based on the WGS-84 datum,
which covers the entire world. Other datums may also cover the entire
world, or just a small portion. By default, your position shows using the
WGS-84 datum. However, it can show your position using one of 191
different datums.
To change the datum, first press the MENU key,
then highlight the “GPS Setup” label and press
the right arrow key. Now highlight the “Select Da-
tum” label. Finally, press the right arrow key again.
A screen similar to the one at right appears.
The WGS-84 label is highlighted. To change it,
simply press the up or down arrow keys to high-
light the desired datum, then press the ENT key.
This selects the datum and erases the select datum menu.
A list of the datums used by this unit is in the back of this manual.
Map Fix
Map Fix is used with charts or maps. This system asks for a reference
position in latitude/longitude, which you take from a marked location on
the map. It then shows the present position as distance on the map from
that reference point. For example, if it shows a distance of UP 4.00” and
LEFT 0.50”, you then measure up four inches and to the left a half-inch
from the reference point on the map to find your location.
To use this format, you need to follow these steps in order. First, take your
map of the area and determine a reference latitude/longitude. (Note: in
order for this system to work, the latitude/longitude lines must be parallel
Summary of Contents for AccuMap
Page 1: ...INSTALLATION AND OPERATION INSTRUCTIONS AccuMap and UltraMap TM TM ...
Page 6: ...Notes ...
Page 90: ...84 Notes ...
