Furuno NAVIONICS GP-1850F - Manual (Page 22)

2-8
2.10 Erasing Weak Echoes
Dirty water or reflections from plankton may
be painted on the display in green or light
blue. These weak echoes may be erased as
follows:
1. Press the [MENU] key and the soft key
SOUNDER SETUP OPTIONS.
2. Select SIGNAL LEVEL, and press the soft
key EDIT to show the signal level window.
SIG LVL
▲
' OFF
™ SL1
™ SL2
™ SL3
™ SL4
™ SL5
™ SL6
▼
SIG LVL
▲
' OFF
™ SL1
™ SL2
™ SL3
▼
At 16-color display At 8-color display
(See page 2-9.)
Figure 2-24 Signal level window
3. Press ▲ or ▼ to select level of erasure;
OFF or signal level among SL1 to SL6
(or SL3). The higher the number the stron-
ger the echo will be erased.
4. Press the soft key RETURN and the
[SNDR] key to finish.
Weak
echoes
Figure 2-25 Appearance of weak echoes
2.11 White Marker
The white marker functions to display a par-
ticular echo color in white. For example, you
may want to display the bottom echo (red-
dish-brown) in white to discriminate fish ech-
oes near the bottom. Note that the bottom
must be displayed in reddish-brown for the
white marker to function.
1. Press the [MENU] key and the soft key
SOUNDER SETUP OPTIONS.
2. Select WHITE MARKER, and press the
soft key EDIT to open the white marker
window.
WHITE MARKER
▲
3
▼
Figure 2-26 White marker window
3. Press ▲ or ▼ to select color to display in
white. As you press ▲ or ▼ , the number
(corresponds to echo number) in the
marker window changes, the white
marker on the color bar shifts and selected
echo color is displayed in white. When you
select 8 in HUE window (See page 2-9.),
white marker is among 0 to 8.
←
White marker shows
color currently
displayed in white.
Figure 2-27 Color bar when white
marker function is active
4. Press the soft key RETURN and the
[SNDR] key to finish.
To turn the white marker function off, display
“0” in the white marker window.