Finding Echo Strength (A-Scope Display); Suppressing Interference And Noise - Furuno CH-300 Operator's Manual

4.10.2

Finding echo strength (A-scope display)

The A-scope display shows echoes at each transmission with amplitudes and tone
proportional to their intensities on the right 1/4 of the screen. It is useful for estimating the
kind of fish school and bottom composition.
1. Press the MENU key.
2. Press ▲ to choose MENU.
3. Press ◄ or ► or to choose ES.
4. Press ▼ to choose A-SCOPE.
5. Press ◄ or ► to open the dialog box.
A-SCOPE
OFF ON
6. Press ► to choose ON.
7. Press the MENU key to close the dialog box.
4.10.3

Suppressing interference and noise

You may encounter occasional noise or intermittent interference on the display. This is
mostly caused by electrical equipment, engine, propeller noise from own ship, or noise from
other sonars being operated nearby. If interference appears, turn on the interference
rejector in the COM1 menu to suppress it. Note that the interference rejector cannot be
turned on/off independently for each frequency in case of the dual-frequency display.
Interference
from other
sounder
Echo sounder picture
Depth, Water Temp. Display
A-scope display
Interference
from other
sonar
Interference
4. ECHO SOUNDER MODE
A-scope display
Electrical
interference
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