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R E F E R E N C E
Main Menu—
Navigation Setup
Submenu
Map Datums (cont)
To define a user datum:
1. Highlight the ‘MAP DATUM’ field, and press
ENTER.
2. Scroll through the map datum options until ‘User’
appears, and press
ENTER.
3. Enter the five parameters of the map datum—‘DX’,
‘DY’, ‘DZ’, ‘DA’, and ‘DF’—using the rocker keypad,
and press
ENTER. The signs of each value should
follow the convention: WGS 84 +/- local geodetic
system.
4. Highlight ‘SAVE?’, and press
ENTER.
CDI Scale
The course deviation indicator (CDI) field lets you
select the range of the CDI bar scale on the Highway
Page. Four scales are available: +/- 0.02, 0.25 (default),
1.25, and 5.0 miles or kilometers. Note: This CDI value
represents the full scale limits (left or right from center)
of the CDI.
To enter a CDI scale setting:
1. Highlight the ‘CDI’ field, and press
ENTER.
2. Select the desired setting, and press
ENTER.
Units of Measure
The GPS 12 CX lets you select statute (default), nau-
tical, or metric units of measure for all speed and distance
readouts.
To change the unit of measure:
1. Highlight the ‘UNITS’ field, and press
ENTER.
2. Select the desired units of measure, and press
ENTER.
Heading Reference
The GPS 12CX’s heading information can be displayed
referencing magnetic north (automatic or user-defined),
true north, or calculated grid headings. The default set-
ting is automatically-calculated magnetic north, which is
suitable for most applications.
To select a heading reference:
1. Highlight the ‘HEADING’ field, and press
ENTER.
2. Select the desired heading reference, and press
ENTER.
To enter a user-defined magnetic heading:
1. Select ‘User Mag’ and press
ENTER.
2. Enter the degrees and direction of magnetic variation,
and press
ENTER.
Units of Measurement
S e t t i n g s
Heading Settings
CDI Scale Settings