3. TARGET TRACKING (TT)
3-18
2. Push the left button to display VECTOR TRUE-S(or -G) or VECTOR REL as
appropriate. (Note that this also selects the vector mode for the past position
display.)
3. Do one of the following to select a vector time.
Control Available
setting
Left button 30 sec, 1-15 min (1 min interval), 20 min, 30 min, 40 min,
50 min, 60 min
Scrollwheel 30 sec, 1-60 min (1 min interval)
The vector tip shows an estimated position of the target after the selected vector
time elapses. It can be valuable to extend the vector length to evaluate the risk
of collision with any target.
3.11
Past Position Display
The past position display shows equally time-spaced dots marking the past
positions of any targets being tracked.
A new dot is added every minute (or at other preset time intervals) until the
preset number is reached. If a target changes its speed, the spacing will be
uneven. If it changes the course, its plotted course will not be a straight line.
Past position orientation, true or relative, is controlled with TRAIL MODE on the
TRAIL menu. See section 1.30.1 for the procedure.
(a) Ship turning
(b) Ship running
straight
(c) Ship reduced
speed
(d) Ship increased
speed
Past position display
3.11.1
Displaying and erasing past position points, choosing past
position plot interval
1. Use the trackball to select the PAST POSN box.
PAST POSN REL 2MIN
PAST POSN box
2. Push the left button or scrollwheel to select plot interval desired: OFF, 30
seconds, 1, 2, 3 or 6 minutes. Select OFF to erase all past position points
and deactivate the past position display.
