Raymarine RL70C, Owner'S Handbook Manual

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62 HSB Series LCD Display
Interference Rejection
Mutual radar interference is likely when two or more radar-equipped vessels are
operating within range of each other. This usually appears as a series of small
dots moving to and from the display centre in a straight line or a long, sweeping
curve. This type of interference is most noticeable at long ranges.
D1639-1
The Pathfinder Radar includes a mechanism that automatically reduces such
interference. This mechanism is normally left switched on. However, if you
wish to detect the presence of other radars in the vicinity, you can turn off the
interference rejection.
Target Expansion
On radome scanner ranges from ½ nm to 3 nm and open array ranges from
1
/
8
to
3 nm you can make targets easier to see by expanding them. Target expansion
overrides the normal pulse length, thereby increasing the size of the target seen
on the screen. However, this is at the expense of range resolution.
Target Wakes
You can see the direction and speed with which targets are moving relative to
your vessel by selecting the target wakes display option.
When wakes are switched on, the target is displayed at the brightest level and
the previous positions of targets are retained at successively fainter levels on the
screen. You can select long, medium or short wakes, which retain information
from previous scans at a reduced video level.
You can clear existing wakes from the display by pressing the
CLEAR WAKES
soft key. The soft key is only available when wakes are switched on; the display
starts showing new wakes as soon as the old wakes have been cleared.
When wakes are switched off, no new wakes are displayed, but existing wakes
are retained.
Changing the
Targets Display
INT REJ
OFF ON
EXPANSION
OFF ON
CLEAR
WAKES
WAKES
OFF S M L