Furuno NAVIONICS GP-1850F - Manual (Page 17)

2-3
Selecting sounder display mode
There are five display modes from which to
choose: normal, marker zoom, bottom zoom,
bottom lock and A-scope. To select a display,
press the soft key SNDR FUNC on the nor-
mal sounder display to show the sounder
function window, and press
▲ or ▼ to select
the display. Press the soft key RETURN to
close the window.
SOUNDER FUNCTION
▲
' NORMAL
™ MARKER ZOOM
™ BOTTOM ZOOM
™ BOTTOM LOCK
™ A-SCOPE
▼
Figure 2-6 Sounder function window
Marker zoom display
This mode expands a selected area of the
normal sounder picture to full vertical size of
the screen on the left-half window. You may
specify the portion to expand by operating
the VRM (Variable Range Marker), which you
can shift with
▲ or ▼ . The area between the
VRM and zoom marker is expanded. The
length of the segment is equal to one divi-
sion of the depth scale.
200k
162
0
50
100
150
200
90.0
100
200
150
Marker zoom
display
Fish school
Normal
sounder
display
Fish
school
This part
is zoomed.
Zoom marker
(yellow)
VRM
(white)
DGPS3D
Figure 2-7 Marker-zoom display
plus normal sounder display
Bottom-zoom display
This mode expands bottom and bottom fish
echoes two to five times to vertical size of
the screen, and is useful for determining bot-
tom hardness. A bottom displayed with a short
echo tail usually means it is a soft, sandy
bottom. A long echo tail means a hard bot-
tom.
200k
162
0
50
100
150
200
40.0
160
100
120
140
180
Bottom zoom
display
Bottom
Normal
sounder
display
Zoom
marker
(yellow)
DGPS3D
Figure 2-8 Bottom-zoom display plus
normal sounder display
Bottom-lock display
The bottom-lock display provides a com-
pressed normal picture on the right half of
the screen and a 5 or 10 meter (10 or 20
feet) wide layer in contact with the bottom is
expanded onto the left half of the screen. This
mode is useful for bottom discrimination.
200k
162
0
50
100
150
200
68.3
0
10
20
30
40
50
This part
is zoomed.
Fish
school
Bottom-lock
display
Fish
school
Zoom
marker
(yellow)
Normal
sounder
display
DGPS3D
Figure 2-9 Bottom-lock display
plus normal sounder display
Note: The zoom marker is not displayed in
the default setting. It may be turned on in the
DISPLAY SETUP2 menu. For further details
see “ZOOM MARKER” on page 9-4.