Furuno GP-1650F, GP-1650DF manual Automatic Sounder Operation, Manual Sounder Operation

2.5Automatic Sounder Operation

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

How the automatic sounder works

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

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

•The gain is automatically adjusted to dis- play the bottom echo in reddish brown (de- fault color arrangement).

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

Two types of automatic sounder modes

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

How to enable automatic sounder operation

1.To show the mode/freq window:

Normal sounder display: Press the soft key MODE/FREQ.

Plotter/sounder display: Press the soft key SNDR, MODE/FREQ in order.

Dual-frequency display: Press the soft

key MODE.

MODE/FREQ

▲

'AUTO CRUISING ™AUTO FISHING

™MANUAL

▼

Figure 2-14 Mode/frequency window

2.Press ▲ or ▼ to select AUTO CRUISING or AUTO FISHING.

3.Press the soft key RETURN to close the window automatically, or wait 10 seconds and the window closes automatically.

2.6Manual Sounder Operation

Manual operation is useful for observing fish schools and bottom using fixed gain setting.

The gain, range and range shifting functions used together give you the means to select the depth you can see on screen. The basic range can be thought of as providing a “win- dow” into the water column and range shift- ing as moving the “window” to the desired depth.

Selecting the manual mode

1.Press the appropriate soft key to show the mode/freq window.

2.Select MANUAL.

3.Press the soft key RETURN.

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