Furuno FR-8122 EU - Manual (Page 21)

1. OPERATIONAL OVERVIEW
1-10
Automatic resetting of own ship marker in true motion mode
1.8 Choosing a Range Scale
The selected range scale, range ring interval and pulse length are shown at the upper left corner
on the screen. When a target of interest comes closer, reduce the range scale so that it appears
in 50-90% of the display radius.
Use the RANGE key to choose range desired. Hit the "+" part of the key to raise the range;
the "-" part to lower the range.
Heading
line
North
marker
(a) True motion
is selected
(b) Own ship has reached a
point 75% of display radius
(c) Own ship is automatically
reset to 75% of radius