Navman Tracker 5430 Installation And Operation Manual page 29

Map datum and map shift
Satellite derived positions on the TRACKER
are based on a worldwide reference (datum)
known as WGS84. Most paper charts are based
on WGS84. However, some paper charts are
not based on WGS84, which results in an offset
between a position on the TRACKER and the
same position plotted on the paper chart.
To match the TRACKER's positions with a local
chart that is not based on WGS84:
Either select Map datum and select the datum
for the local chart. See appendix A for a list of
the available datums. WGS84 is the default
datum, and the datum most commonly used
on paper charts.
Or, if the correct datum is not available, retain
the WGS84 datum and apply a map shift.
(see below).
NMEA datum off set
If you select a map datum other than WGS 84,
the map datum offset can be applied to latitude
and longitude coordinates sent on the TRACKER
NMEA output:
Off: Latitude and longitude coordinates
displayed on any NMEA repeater do not
match the coordinates on the TRACKER.
Latitude and longitude coordinates
broadcast on any NMEA VHF transmitter
will be the same as the coordinates on a
WGS 84 chart.
On: Latitude and longitude coordinates
displayed on any NMEA repeaters match
the coordinates on the TRACKER. However,
latitude and longitude coordinates broadcast
on any NMEA VHF transmitter will be slightly
offset from coordinates on a WGS 84 chart.
Map shift
Map shift is a correction applied to the TRACKER's
positions so that they match a chart's positions.
Warning: Map shift is for eliminating
minor offsets. It should not be used if the
correct datum is available. Use map shift
with caution: incorrect application will cause
incorrect boat positions.
NAVMAN
TRACKER 5430/5430i Installation and Operation Manual
Set map shift
1 Move the boat to a known point on the chart,
for example a marina berth.
2 In the Chart setup menu, select Map shift.
3 Move the cursor to the position on the chart
where the boat actually is.
4 Press ENT to set the new map shift. The boat
will now be displayed at its actual location.
Clear map shift
Clearing the map shift removes any map shift
from the TRACKER's positions.
1 In the Chart setup menu, select Map shift.
2 Press MENU and select Clear.
Waypoints
Controls how waypoints are displayed on the
chart. The options are:
Hide all: No waypoints are displayed. (
except for waypoints on any selected route).
Show all: All waypoints are displayed.
Selected: Waypoints with their display
option set to Icon or I+N (Icon and Name) are
displayed (see section 9).
Chart display options
The other chart setup options allow an extensive
range of chart card features to be shown.
Configure the most useful display format.
Bathymetric Lines and soundings
Chart cards contain a large amount of spot
sounding and depth contour data. This can be
selectively displayed by turning Bathymetric
Lines and Spot Soundings on, then selecting
the range to display with Bath and Sndgs Min
and Max.
Attention Areas
Areas of importance, such as restricted
anchorages and shallow areas, are highlighted as
Attention Areas. The options are:
On: displays attention area boundaries and
information icons .
Off: does not display attention area
boundaries or information icons .
Note: In some early chart cards the information
icons are inactive.
29