Furuno FCV-582L manual Suppressing Interference, Suppressing Low Level Noise

1.14 Suppressing Interference

Interference from other acoustic equipment operating nearby or other electronic equip- ment on your boat may show itself on the dis- play as shown in Figure 1-27.

To suppress interference, do the following:

1.Select MENU with the MODE control.

2.Select NOISE LIMITER.

3.Press the [+] or [–] key to select degree of suppression desired; OFF, NL1, NL2 or NL3. The higher the number the greater the degree of suppression.

3.Press the [+] or [–] key to select clutter rejection level desired. The higher the number the higher the degree of suppres- sion. Note that weak echoes may not be displayed when the clutter circuit is on.

Figure 1-28 Clutter appearance

Interference from	Electrical inteference
other sounder

Figure 1-27 Interference

Turn the noise limiter circuit off when no in- terference exists, otherwise weak echoes may be missed.

1.15Suppressing Low Level Noise

Light-blue dots may appear over most of screen. This is mainly due to dirty water or noise. This noise can be suppressed by ad- justing CLUTTER on the User menu.

When the automatic mode is on, the clutter suppression setting is fixed at AUTO. To sup- press low level noise in manual sounder op- eration do the following:

1.Select MENU with the MODE control.

2.Select CLUTTER.

1.16Selecting Background and Echo Colors

1.Select MENU with the MODE control.

2.Select HUE.

3.Press the [+] or [–] key to select hue num- ber. (You can see the result of your selec- tion on the display.)

Table 1-2 Background and echo colors

Hue	Echo Color	Background Color
No.
1	16 color	Medium-blue
2	8 color	Medium-blue
3	16 color	Dark-blue
4	8 color	Dark-blue
5	16 color	White
6	8 color	White
7	16 color	Black
8	8 color	Black
9	Monochrome, 8 intensities

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