Furuno 1943C Benutzerhandbuch

Seite von 251
2. RADAR OPERATION 
 
 
 
2-4
2.5 
Reducing Sea Clutter 
2.5.1 
How the A/C SEA works 
Echoes from waves can be troublesome, covering the central part of the display 
with random signals known as “sea clutter”. The higher the waves and the higher 
the antenna above the water, the further the clutter will extend. Sea clutter may 
affect radar performance because real targets are sometimes hidden by the 
echoes of small waves. (See the left-hand figure in the figure below.) When sea 
clutter masks the picture, adjust the A/C SEA to reduce the clutter. 
 
The A/C SEA reduces the amplification of echoes at short ranges (where clutter 
is the greatest) and progressively increases amplification as the range increases, 
so amplification will be normal at those ranges where there is no sea clutter.   
A/C SEA adjusted;
sea clutter suppressed
Sea clutter at
screen center
 
Effect of A/C SEA 
2.5.2 Adjusting 
the 
A/C 
SEA 
A/C SEA should be adjusted so that the clutter is broken up into small dots, and 
small targets become distinguishable. 
 
1.  Press the [GAIN] key. 
2.  Press the A/C SEA soft key to show the A/C SEA setting window.   
A/C SEA

 ¡
 
AUTO ROUGH
¡
 
AUTO MODERATE
¡
 
AUTO CALM
 ¤
 
MAN
Model 1700 series radar
A/C SEA
Model 1800/1900 series radar
0
0
 
A/C SEA setting window 
3.  When the radar source is the Model 1700 series, use the trackball to 
select AUTO ROUGH, AUTO MODERATE, AUTO CALM, or MAN (manual) 
as appropriate. Select an AUTO option according to the sea state. 
4.  For manual adjustment, rotate the [ENTER] knob to adjust. The range of 
adjustment is 0-100(%). Do not overadjust – weak echoes may be missed.