Furuno 1830 User Manual

REDUCING OR ELIMINATING INTERFERENCE
Uasically tht?re ait Ihiee types uf interference wtlicfi may nlnder radar
reception: sea dutter, due to echoes off waves (mentioned earlier);
precipitation dutter and interference from other shipborne radars operating
nearhy and nn the same freqnenoy band. This radar oan eliminate or
reduce these types of inlerference.
Precipitation Interference
The vcrtical beamwidth of the scanner is designed to see surface targets
oven when the ship is rolling. Hovvever, this design alao has its disadvan
tages: rain storms, snow, or hail are detected in the same manner as normal
targets. Precipitation dutter is easily recognizable by its wool-like
appearance on~screen (see Fig.29). When this typ e of interference obscures
a large area of the screen, you may use the touchpad to eliminate or
reduce the interference.
The FTC (Fast Time Cunstaiit) Circuit worKs by splitting up these unwanted
echoes into a speckled pattern, making recognition of solid targets easier.
Because its efl'ect upon the piclure is to weaken it, but because it breaks
up solid echoes. it also makes for betler definition. For this reason, it may
be switched on to clarify the picture when navigating in confined waters.
However, with the Circuit activated the receiver is less sensitive, weaker
echoes may be missed. The^fore, deactivate the Circuit when no
interference exists. Press the [^] touchpad and you will see the indicator
"FTC" appears at the upper-riglTt hånd side of the display screen. The
Circuit is switched off by pressing the touchpad again.
(A) rain squall,
FTC "OFF"
(B) FTC Circuit "ON"
interference reduced
Fig.29 Precipitation Interference
Kadar Interference
Kadar interference may occur when in the vicinity of another shipborne
radar operating in the same frequency band. It usually is seen on the
display screen as a large number of bright dots either scattered at random
or in the form of dotted lines extending from the center (or the edge) to
the edge (or the center) of the display screen. Fig.30 illustrates
int(?rferf?neG in the form nf niirved qpokes. [nterference effeots are easily
distinguished from normal echoes because thcy do not appear in the same
place on successive rotations of the scanner.
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Furuno 1830 Specifications

General

Brand	Furuno
Model	1830
Category	Marine Radar
Language	English