Furuno NAVNET 1823C - Manual (Page 46)

2. RADAR OPERATION
2-10
North-up
In the north-up mode, targets are painted at their measured distances and in
their true (compass) directions from own ship. North is maintained at the top of
the screen. The heading line changes its direction according to ship’s heading.
Heading Line
North
North-up presentation mode
True motion
Fixed radar targets maintain a constant position on the screen, while your own
ship moves across the radar image at the correct speed and heading. A map-like
image is displayed, with all moving vessels traveling in true perspective to each
other and to fixed landmasses. As your ship’s position approaches the edge of
the screen, the radar display is automatically reset to reveal the area ahead of
your ship. You can manually reset your ship’s position at any time by pressing
the RADAR DISPLY soft key followed by the SHIFT soft key.
Heading Line
North
True motion presentation mode