JRC JMA-7710-6 Instruction Manual page 174

(1) True Vector Display
In the true vector mode, the direction of the target vector becomes the length proportional to the true speed
of the target true course, length target.
The vector of the own ship is also displayed as shown in the figure.
By using this mode, the motion of ships around the own ship can accurately and easily be grasped.
In this mode, the CPA ring cannot be displayed.
(2) Relative vector display
The relative vector displays the relative relationship with the own ship instead of displaying the true motion
of the target. In other words, the target in which this relative vector faces to the direction of the own ship
(passes through the CPA ring) is dangerous.
In the relative mode, the place where the CPA (closest point of approach) of the target is located can be
known at a glance.
Therefore, each mode can be used properly according to the purpose. For example, the true vector is used to
grasp the true motion of the target and the relative vector is used to grasp the closest point of approach of the
target.
HL
True vector
The relative vector is not displayed.
HL
The true vector is not displayed.
Relative vector
CPA ring
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