Sample Echo Displays; Bottom Echoes - Furuno CH-250 Operator's Manual

2.14.2 Sample echo displays

Bottom echoes

When the tilt angle is changed, the bottom echo illustrated below will appear on the display.
When the tilt is decrease (toward 0 ), the bottom trace becomes winder and weaker. By
observing the bottom condition on the display, the skipper can prevent net damage.
(A) Flat bottom
Tilt angle: 10˚ to 15˚
(B) Flat bottom
Tilt angle: 20˚ or more
(C) Sloping bottom
Tilt angle: 20˚ or more
2-24
Decreased tilt angle
Only half of
vertical beam width
captures the bottom.
Bottom is displayed
narrower and in
stronger colors when
compared to (A).
Shallow bottom
is displayed in
a strong color
and with a
short tail.
Bottom
Figure 2-21 Bottom echoes
The deeper, sloping
bottom echo is displayed
in a weak color and
with a long tail.