Navigation Setup
The navigation setup page is used to select units of
measurement for position formats, map datums, CDI
scale, as well as distance, speed and heading information.
Position Formats
The default position setting for the GPSCOM 170 is
latitude and longitude in degrees and minutes
(hdddºmm.mmm’). You may also select degrees, minutes
and seconds (hdddºmm’ss.s’’); degrees only
(hddd.dddddº); UTM/UPS coordinates; or British,
German, Irish, Maidenhead, Swedish, Swiss or Taiwan
grid formats.
To select a position format:
1. Highlight ‘POSITION FRMT’ and press
E
. Use the
up and down arrow keys to select the desired setting.
Confirm the setting by pressing
E
.
Map Datums
The map datum field is located just below the posi-
tion format field, and comes with a WGS 84 default set-
ting. Although 104 total map datums are available for use
(see the map datum listing in Appendix F), you should
only change the datum if you are using maps or charts
that specify a different datum than WGS 84.
To select a map datum:
1. Highlight the ‘MAP DATUM’ field and press
E
.
2. Use the up and down arrow keys to toggle through and
select the desired setting. Confirm the setting by
pressing
E
.
CDI Scale Setup
The course deviation indicator (CDI) scale definition
field lets you select the +/- range of the CDI bar scale.
Three scales are available: +/- 0.25, 1.25 and 5.0 miles or
kilometers, with 0.25 being the default setting.
To enter a CDI scale setting:
1. Highlight the ‘CDI SCALE’ field and press
E
. Use
the up and down arrow keys to select the desired set-
ting. Press
E
to confirm the selection.
Navigation
Setup
Reference
59
NAV Setup Page
The position format may be
set to display your position
in various lat/lon or grid
formats.
Map Datum
The GPSCOM 170’s default
map datum is WGS 84.
WARNING: Using the
wrong map datum can seri-
ously affect the accuracy of
your GPS receiver.
170 manual pages rev D 9/21/98 9:23 AM Page 59
