5. AIS Operation
5-16
5.12 How to Display AIS Target Past Positions
The past position display shows equally time-spaced dots marking past positions of activated AIS targets. If a target
changes its speed, the spacing will be uneven. If it changes course, its plotted course will not be a straight line.
Below are sample past position displays.
(a) Ship turning
(b) Ship running
straight
(c) Ship reduced
speed
(d) Ship increased
speed
Sample past position displays
5.12.1 How to display and erase past position points, select past position
interval
1. Use the trackball to select the Past Posn indication at the right side of the screen.
AUTO
MAN
xx.xx xx.xx
Past Posn indication
2. Do one of the following to select a past position time.
Control Available setting
Scrollwheel 1, 2, 3, 5, 6, 10, 12, 15, 20, 30, 40, 50, 60 min
3. Push the left button to confirm selection.
