Distances, Range, And Bearing - Lighthouse a65 Installation And Operation Instructions Manual

20.6 Distances, range, and bearing

When you are using the radar application, you can
measure distances, ranges and bearings in a variety
of ways.
These options are detailed in the table below:
Distances
Between
Functions Points
Range Rings Yes (approx-
imate dis-
tance)
Cursor No
Variable No
Range
Markers /
Electronic
Bearing Lines
(VRM/EBL)
Floating Yes
VRM/EBL
Measuring using the range rings
Use the range rings to gauge the approximate
distances between points. Range rings are
concentric circles displayed on the screen and
centred from your vessel at pre-set distances. The
number and spacing of the rings changes as you
range in and out.
Examples:
D12214-1
Range — 1/4 nm Range — 3/4 nm
Range Rings — Range Rings —
760ft apart 1/4 nm apart
Measuring using the cursor
To measure the bearing and range from your
vessel to a specified target, move the cursor to the
appropriate position on the screen and press Ok,
the radar context menu will be displayed which shall
provide:
• Latitude
• Longitude
• Range
• Bearing
1 2
302
Range
From Your
Vessel Bearings
Yes (approx- No
imate range)
Yes Yes
Yes Yes
No Yes
D12215-1
Range — 1 1/2 nm
Range Rings —
1/4 nm apart
D12217-2
Item
1.
2.
You can also display the cursor position in the
databar, from the homescreen select: Customize
> Databar Set-up > Edit Databar, now select the
data box where you want the cursor position to be
displayed. Select Navigation > Cursor Position.
Measuring using VRM/EBL
Variable Range Markers (VRM)
A Variable Range Marker (VRM) is a circle centred
on your vessel's position and fixed with respect to
the heading mode. When this circle is adjusted to
align with a target, its range from your vessel is
measured and displayed on the Radar context menu
when you select the VRM with the cursor.
Electronic Bearing Lines (EBL)
An Electronic Bearing Line (EBL) is a line drawn
from your vessel to the edge of the window. When
this line is rotated to align with a target, its bearing
relative to your vessel's heading is measured and
displayed on the Radar context menu when you
select the VRM with the cursor.
The VRM/EBL are combined to measure both the
range and the bearing of the specified target.
D12216-1
Item
1
2
3
4
Measuring using floating VRM/EBL
You can use the VRM/EBL float function to measure
the range and bearing between any two points on the
radar screen. This function allows you to move the
VRM/EBL centre away from your vessel's position
and onto a target. You can then change the radius
of the VRM to determine the distance between two
points and change the angle of the EBL, relative to
its new origin, to obtain the bearing.
Description
Cursor
Bearing and range from your
vessel to the cursor position
1 2 3 4
0.624nm
56°S
VRM /EBL
Description
VRM
Target
EBL
Range and bearing
a Series / c Series / e Series