Sidelobe Suppression - Furuno FSV-84 Operator's Manual

2. HORIZONTAL MODE
2.9.10

Sidelobe suppression

Sidelobes are fairly emissions generated outside the main beam. The energy of
the sidelobe is fairly weak but when the water is comparatively shallow and the
bottom is rocky and hard, strong signals are detected by the sidelobe.
To reduce the effect of sidelobes, adjust SIDELOBE SUPPRESS from the
H-SCAN SETTING menu. The setting range is –3 to +3 and the default setting is
0. The higher the setting the greater the sidelobe suppression. If there is a
difference between the port and starboard side images, use a minus setting.
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