TRACKFISH 6500
Installation and Operation Manual
33
NAVMAN
Bottom types
Mud, weed and sandy bottoms tend to weaken
and scatter the sonar pulse, resulting in a weak
echo. Hard, rocky or coral bottoms reflect the
pulse, resulting in a strong echo.
A
C
D
B
A Single fish
B Large school of fish
C Small school of fish
D Bottom
A Kelp / Weed
B Soft bottoms such as mud, weed and sand
show as narrow bands
C Hard bottoms such as rock or coral show as
wide bands
A
C
B
Frequency and cone width
Water
Cone width
Cone width
Depth
at 50 kHz
at 200 kHz
25
20
5
50
40
10
100
80
20
150
130
30
200
170
40
300
250
60
400
330
80
600
500
120
800
660
150
1000
830
190
45° cone
11°
cone
The sonar pulse
generated by the
TRACKFISH transducer
travels down through
the water, spreading
outwards in a cone
shape. The cone width
is dependent upon
the frequency of the
pulse; at 50 kHz it is
approximately 45°,
and at 200 kHz it is
approximately 11°.
The differences in the
cone width affect what
is displayed. See
section 8-3.
