NorthStar 961 Reference Manual page 281

Geodetic
datum
961/962 Operations and Reference Manual, Rev. A
At the NAVIGATION SETUP screen, you can view or edit any of
the following options:
• geodetic datum
• preferred loran GRI
• waypoint switching
• magnetic variation
• distance, bearing, and steering calculations
Each of these options is described in detail below.
If you're viewing and editing information on the
SETUP
screen, and you press one of the five function keys to view
other data, your edit-in-progress is immediately cancelled so you
can view the data requested by your function keypress. To resume
NAVIGATION SETUP
editing at the
that screen and re-enter the data you lost when you pressed the
function key. To purposely cancel an edit-in-progress, however,
you'd normally press the
Different regions of the world have various models for lat/lon
coordinates on their charts; each model is called a datum. The
datum used on the CHART screen always matches that of the
chart-in-use. The non-chart screens and the serial data input
and output use the same datum as chart view A, unless you
change the GEO DATUM setting from auto to manual. Once in
manual, you then select the datum you want to use for
non-chart screens and serial data. Note that when you set
geodetic datum to manual, the same physical location, such as
a waypoint, may have slightly different coordinates on the
CHART screen and non-chart screens.
All referenced datums are listed, according to Defense
Mapping Agency publications, in the geodetic datum option.
To change the non-chart screen datum reference:
1. At the NAVIGATION SETUP screen, press the CURSOR
PAD to highlight the GEO DATUM option, then press the
EDIT key.
2. Press the CURSOR PAD right or press the ARROW keys
to select MAN (for manual), then press the ACCEPT key.
Chapter 13 - Customizing Setup Functions
NOTE:
screen, you must return to
CANCEL
key.
NAVIGATION
Page 13-11