44
Units Page
The Units features are best used by individuals with
a working knowledge of map grids and datums. To learn
more about these subjects, visit the National Imagery and
Mapping Agency at http:// www.nima.mil or inquire at
your library.
Position Format -
Allows you to choose from
different grid formats. The default position format,
‘hddd°mm.mmm’ displays the latitude and longitude in
degrees and minutes and is most commonly used.
Map Datum -
Offers a selection of nearly all map
datums in common use. Every map is based on a map
datum (a reference model of the earth’s shape) and is
usually listed in the title block of the map. If you are com-
paring GPS coordinates to a paper map, chart, or other
reference, the map datum in this fi eld must match the
horizontal map datum used to generate the map or other
reference. The default datum is WGS 84 (World Geodetic
Survey 1984). If a map does specify a datum, use the
options list to fi nd datums applicable to the region of the
map, selecting the one that provides the best positioning
at a known point. If necessary, you also may choose the
‘User’ datum for custom designed grids.
Distance/ Speed -
You can choose from three units of
measure to display your rate of travel.
Elevation -
You can choose from two units of mea-
sure to display your elevation.
Vertical Speed -
You can choose from three units of
measure to display your rate of ascent and descent.
Depth -
You can choose from three units of measure
to display the depth of an area shown on a map.
To select Units Page options:
1. For all fi elds on this page, highlight the fi eld and
then press the
CLICK STICK
to display the Options
Menu for the fi eld.
2. Highlight the desired option on the menu and then
press the
CLICK STICK
to place it in the fi eld.
Setup Options
Main Menu
Units Page
Position Format
Options Menu
Map Datum Options
Menu
Depth Options
Vertical Speed
Options
Distance/Speed
Options
Elevation Options
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