Noise Limiter; Echo Average; Reverberation Reduction; Setting Reference Bearing For Frequency Change - Furuno FSV-84 Operator's Manual

2.9.5

Noise 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.
2.9.6

Echo 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.
2.9.7

Reverberation 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.
2.9.8

Setting 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.
2.9.9

Suppressing 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.
2. HORIZONTAL MODE
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