Furuno FCR-2119-BB, Operation Manual

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2. RADAR, CHART RADAR OPERATION
2-22
2.17.2 How to select bearing reference
An EBL box has an "R" (relative) if the EBL bearing is relative to own ship's heading;
"T" (true) if it is referenced to the north. True or relative indication is available regard-
less of presentation mode.
To change the bearing reference, click the EBL reference indication to display R or T
as appropriate. The bearing reference can also be selected on the [EBL•VRM] menu
([EBL•VRM•CURSOR] menu with the IMO- and A-type radars).
Note: When the gyrocompass heading changes, the EBL and its indication change as
follows:
2.18 Collision Assessment by Offset EBL
The origin of the EBL can be placed anywhere with the trackball to enable measure-
ment of range and bearing between two targets. This function is also useful for as-
sessment of the potential risk of collision. It is possible to read CPA (Closest Point of
Approach) by using a VRM as shown in Figure (a) on the next page. If the EBL passes
through the sweep origin (own ship) as illustrated in Figure (b), the target ship is on a
collision course.
2.18.1 How to assess risk of collision
How to assess risk of collision from the Control Unit
1. Press the EBL1 or EBL2 key to activate an EBL.
2. Put the cursor on a target that appears as a threatening target (A in the figure on
the next page).
3. Press the EBL OFFSET key to shift the EBL origin to the cursor location.
4. Wait approx. three minutes. Operate the EBL rotary control to bisect the target at
the new position (A'). The EBL indication shows the target ship's course, which
may be true or relative depending on the EBL bearing reference setting.
5. If relative motion is selected, it is also possible to read CPA by using a VRM as
shown in the left figure on the next page. If the EBL passes through the sweep
origin (own ship) as illustrated in the right figure on the next page, the target ship
is on a collision course.
To return the EBL origin to the center of the screen, press the EBL OFFSET key.
Course-up, relative:
Course-up, true:
Head-up, relative:
Head-up, true:
North-up, relative:
North-up, true: EBL indication remains the same, EBL moves.
EBL indication and EBL remain unchanged.
EBL indication and EBL remain unchanged.
EBL indication remains the same; EBL moves.
EBL indication remains the same, EBL moves.
EBL indication and EBL remain unchanged.