Onwa Marine Electronics KR-1338C v.2 - Manual (Page 8)

Past Position Display
The past position display shows equally time-spaced dots marking past
positions of activated AIS targets. A new dot is added at preset time intervals
until the preset number is reached. 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 turning
Straight
(c) Ship reduced (d) Ship increased
speed speed
Figure 9 Sample past position displays
Past position plot interval
Enter AIS menu, select 5.History t o s elect p lot in terval d esired: O ff,
15 s,30 s, 1, 2, 3 or 6 min. Select OFF to erase all past position points and
turn off the past position display.
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