Furuno FSV-84 manual Noise limiter, Echo average, Reverberation reduction

2. HORIZONTAL MODE

2.9.5Noise limiter

Weak, unwanted reflections, colored light-blue or green, appear when the water is dirty, plankton layers exists, or due to ship’s noise. The noise limiter can reduce the effects of these unwanted reflections. Raising the setting causes unwanted reflections to be displayed in colors of blue to background color. Normally a setting of 3 or 4 is sufficient.

1.Press the [MENU] key to open the menu.

2.Select the H-SCAN SETTING menu and press the [MENU] key

3.Select NOISE LIMITER and press the [MENU] key.

4.Adjust setting from the dialog box as appropriate and press the [MENU] key. The setting range is 0-15. The higher the setting the greater the degree of suppression.

5.Select QUIT and press the [MENU] key.

6.Select QUIT at the top of the menu screen and press the [MENU] key to close all menus.

2.9.6Echo average

Adjusts echo afterglow, which can be useful for watching echo movement in the H-SCAN SETTING menu. The setting range is 0-7. The higher the number the longer echoes remain on the screen.

2.9.7Reverberation reduction

You may choose the length of reverberation for the echo signal in the H-SCAN SETTING menu. The larger the value the shorter the reverberation, which makes it easer to see the echo signal. The setting range is 0-3.

2.9.8Setting reference bearing for frequency change

The FREQ/BEARING SET function in the H-SCAN SETTING menu is provided for avoiding interference from other equipment.

If noise (interference) appears at a specific bearing, change the value of the FREQ/BEARING SET in the H-SCAN SETTING menu. The setting range is 0° to 358°.

Note: The FREQ/BEARING SET function is active only when the SIDELOBE SUPPRESSION on the SYSTEM MENU is set to 1 or 2. For details, contact a FURUNO agent or dealer.

2.9.9Suppressing gain of bottom echo

None-moving echoes such as bottom echo, plankton echo, etc., may be suppressed by the setting of BOTTOM SUPPRESS in the H-SCAN SETTING menu (moving echoes such as fish school are not effected by this setting). The setting range is 0 to 10. The greater the setting, the greater the suppression level of the bottom, etc.

Note: Avoid using too high a setting - slow-moving fish school may be suppressed as well.

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