Furuno GP-7000F - Manual (Page 78)

8. CUSTOMIZING YOUR UNIT
8-8
NAVIGATE
Item Settings
COORDINATE SYSTEM
Choose the coordinate display method among
ddd mm ss, ddd mm.mm, ddd mm.mmm and
ddd.ddddd for latitude, or TD.
MAP DATUM
Geodetic datum is a reference for geodetic
survey measurements consisting of fixed
latitude, longitude and azimuth values
associated with a defined station of reference.
You must have the correct geodetic datum
selected in your plotter so that it will reference
the correct point on the chart for a given latitude
and longitude. Although WGS-84 is now the
world standard, other categories of charts still
exist.
MAP ORIENTATION North Up, Course Up, Auto Course Up
MAP ORIENTATION RES
Sets the degree to re-draw the course on Auto
course-up mode. (Setting range: 5º to 60º)
COMPASS
Item Settings
BEARINGS
Choose how to calculate bearing, Mag or True. True
bearing is a bearing measured using true North as the
reference direction, and it is calculated by the formula
True Bearing = Magnetic Bearing -Magnetic Variation.
Magnetic bearings are measured with magnetic north as
the reference direction. Select Mag when using a
magnetic compass, True when using a gyrocompass.
VARIATION
The location of the magnetic north pole is different from
the geographical north pole. This causes a difference
between the true and magnetic north location. This
difference is called magnetic variation, and varies with
respect to the observation point on earth. Your unit is
preprogrammed with all the earth’s magnetic variations.
However, you may wish to enter variation manually to
refine accuracy by entering the magnetic variation
referring to a nautical chart.
CALIBRATION
Enters eight directions (N, N/E, E, S/E, S, S/W, W, N/W)
deviation values for magnetic compass.