Sonar 50/200 Display; Sonar A-Scope Display - Navman TRACKFISH 6600 Installation And Operation Manual

9-4 Sonar 50/200 display

50 kHz 200 kHz
sonar history
sonar history

9-5 Sonar A-Scope display

Sonar history
A-scope display
The display shows the sonar history on the
left and the A-Scope display on the right. The
A-Scope shows:
• the strengths of echoes from different
depths - the longer the horizontal line the
stronger the signal
• a vertical line showing the gain threshold,
TRACKFISH 6600 Installation and Operation Manual
The display shows the 50 kHz sonar history on
the left and the 200 kHz sonar history on the
right. Gain can be set independently for each
frequency (see section 8-5). Range applies to
both frequencies (see section 8-6).
•
Threshold
line
Unwanted
Use the A-Scope while adjusting the gain and
noise
threshold settings manually (see section 8-5).
signal
Fish recognition
The echo strengths shown on the A-scope
Peak of
can be useful in recognising the type of fi sh.
bottom
Different species of fi sh have different sizes
signal
and shapes of swim bladders. The air in the
swim bladder refl ects the ultrasonic pulse, so
Gain line
the strength of the echo varies between fi sh
species according to the size and shape of the
swim bladder.
When catching fi sh from a school, note the
species and the strength of the echo that
it returns on the A-scope. Then, when that
particular echo is seen again, it is likely to be
the same fi sh species.
Bottom type
The shape of the echo strengths in the A-Scope
can help you to recognise the type of bottom.
NAVMAN
the weakest echo to display on the sonar
history
a vertical line showing the gain setting;
echoes above this strength will display as
the maximum signal strength
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