Raymarine SL70M - 3.2 Range Control

3-2 SL70M & SL70C PLUS Pathfinder Radar Displays
Range Control
3.2 Range Control
The radar picture can be viewed at various scales. The shortest range scale
gives a maximum range of
1
/
8
nautical miles, measured from the default centre
to the top of the radar picture. The longest range scale gives a maximum range
of between 24 and 72 nautical miles depending on your scanner.
•The long range scales provide the best overview of your vessel’s relation-
ship to land masses, weather fronts and large ship targets in or beyond
view.
•The short range scales provide greater detail of the radar echoes close to
your vessel, and should be used as you approach the coastline, harbour or
other vessels in the area.
The Pathfinder Plus Radar display includes concentric range rings, which you
can use to help you to judge distances on the radar picture. Their number and
spacing are adjusted automatically if you change the range scale. They can be
turned off (see You can use the context sensitive cursor to select and move the
cursor data box (the label BOX is displayed). See Moving and deleting items
with the context-sensitive cursor on page 1-10 on page 2-10).
The Standard Range Scale
Details of the standard ranges that can be selected are shown in the table
below. If you wish, you can customize the range scales by specifying different
ranges, as described in Section 5.4, Radar Set Up Parameters.
* The maximum range depends on your scanner type, as detailed in the Pathfinder Plus Radar
Scanner Owner’s Handbook.
The number of range rings shown in the table is the number to the selected
range. Additional range rings are displayed to the edge of the radar picture, at
the standard ring interval for the current range, and are visible when the centre
is offset.
Table 3-1: Radar Range Scales
Maximum Range
(nm)
Number of Range
Rings
Range Ring Interval
(nm)
0.125
0.25
0.5
0.75
2
2
4
3
0.0625
0.125
0.125
0.25
1.5
3
6
6
0.25
0.5
6
12
24*
48*
72*
6
6
6
6
6
1
2
4
8
12