Furuno GP-3500F - Manual (Page 178)

11. VIDEO SOUNDER OPERATION
11-6
11.2.7 A-scope display (Single display only)
The A-scope display, available in all modes, shows echoes at each transmission
with amplitudes and tones proportional to their intensities, on the right 1/3 of the
screen. It is useful for estimating fish species and seabed composition.
Strong echo
(Bottom)
Normal
display A-SCOPE DISPLAY
Fish school
Weak echo
(small fish school
or noise)
AUTO C
53.6
m
17.6
5.6 °
C 10.0 kt
1'50"
50k
0
20
40
60
80
A-scope display