Furuno 1933, 1943, 1833 manual Erasing Weak Echoes, Appearance of weak echoes, Signal level window

4. VIDEO SOUNDER OPERATION

4.8Erasing Weak Echoes

Sediments in the water or reflections from plankton may be painted on the display as “spots” on the background. These weak echoes may be erased as below.

Weak echoes

Appearance of weak echoes

1.Press the [MENU] key.

2.Press the SOUNDER MENU soft key.

3.Select SIGNAL LEVEL, and press the EDIT soft key to show the signal level window.

SIGNAL LEVEL

▲§

OFF

°SL1

SL2

▼

Signal level window

4.Use the trackball to select level of erasure or OFF as appropriate. The higher the number the stronger the echo that will be erased.

5.Press the RETURN soft key followed by the [MENU] key to close the menu.

Note: Unlike “clutter,” signal level erases echoes. Therefore, if you do not wish to erase echoes, use clutter instead.

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