Furuno GP-7000F Operator's Manual page 97

Marker-zoom display
The marker-zoom display 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 the
[ENTER] knob. The area between the VRM and zoom marker is expanded.
Note 1: The VRM is set independently from other displays in case of multiple displays.
Note 2: The range of the bottom-lock can be changed at BOTTOM LOCK RANGE on
RANGES menu.
Marker
zoom display
25.0
ft
Zoomed fish school
Marker-zoom display plus normal sounder display
Bottom discrimination display
The bottom discrimination mode displays the bottom echo to help you determine 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 bottom.
Note: The range of the bottom discrimination can be changed at BOTTOM LOCK
RANGE on RANGES menu.
Bottom discrimination
display
Seabed tail
Long tail: Hard bottom
Short tail: Soft bottom
Single frequency display
Fish school
20
12.8
30
40
50
50k
10
0
50
79.5
ft
Bottom discrimination display
10. VIDEO SOUNDER OPERATION
0
VRM
This area is zoomed.
50
Zoom marker
100
0
50
100
50k
Single
frequency
display
This area
is zoomed.
10-7