Furuno 1954C-BB, GD-1920C-BB manual Automatic Sounder Operation, How the automatic sounder works

4. VIDEO SOUNDER OPERATION

4.1.3Selecting screen split method in combination displays

On combination sounder displays you can split the screen vertically or horizontally, using the E: SPLIT soft key as below.

LF

0.0

HF

ESPLIT

/

ESPLIT

/

0.0

HF

LF

How to use the SPLIT soft key (example: dual frequency display)

4.2Automatic Sounder Operation

Automatic sounder operation is useful when you are preoccupied with other tasks and do not have the time to adjust the display.

4.2.1How the automatic sounder works

The automatic sounder function automatically selects the proper gain, range scale and clutter suppression level according to the depth. It works as follows:

•The range changes automatically to locate the bottom on the lower half of the screen. The range jumps to one step shallower range when the bottom echoes reach a half way point of the full scale from the top and to one step deeper range when they come to the lower edge of the scale.

•The gain is automatically adjusted to display the bottom echo in reddish brown (default color arrangement).

•Clutter, which suppresses low level noise, is automatically adjusted.

4.2.2Types of automatic sounder modes

Two types of automatic sounder modes are available: CRUISING and FISHING. CRUISING is for tracking the bottom, and FISHING is for searching fish schools. CRUISING uses a higher clutter rejection setting than FISHING therefore it is not recommended for fish detection - weak fish echoes may be erased by the clutter suppression circuit.

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