Furuno 1942 MARK-2 - Manual (Page 18)

2-6
2.12 Measuring the Bearing
There are two ways to measure the bearing
to a target: by the cursor , and by the EBL
(Electronic Bearing Line).
Measuring bearing by cursor
Operate the omnipad to bisect the target with
the cursor intersection. The bearing to the
target appears at the bottom of the display.
Measuring bearing by EBL
1. Press the [EBL/VRM SELECT] key to cir-
cumscribe an EBL readout (at the bottom
left-hand corner). Each press of the key
selects the readout of EBL1, EBL2, VRM1
or VRM2 in that order.
2. Press the [EBL/VRM CONTROL] key to
enable control of the EBL by the omnipad.
3. Operate the omnipad to bisect the target
with the EBL. The omnipad must be op-
erated within five seconds after pressing
the [EBL/VRM CONTROL] key, otherwise
the EBL cannot be operated.
4. Check the EBL readout at the bottom left-
hand corner of the display to find the bear-
ing to the target.
5. To anchor the EBL, press the [EBL/VRM
CONTROL] key.
To erase the EBL and its readout, press and
hold down the [EBL/VRM CONTROL] key
about two seconds.
6.0 NM
2.0
EBL1 bearing
EBL1 bearing
40.0 ° R
135.0 ° R
EBL
EBL1
EBL2
Target
Cursor
Cursor
bearing
40.0 °R 4.0 NM
Figure 2-8 How to measure bearing by EBL
and cursor
Note: The bearing readout for the EBL andthe
cursor can be displayed in relatiive or true
bearing (true bearing requires heading sen-
sor input). For north up and course up dis-
play modes the bearing reference is always
true. For details see the next chapter.
Tips for measuring bearing
¡ Bearing measurements of smaller targets
are more accurate; the center of larger
target pips is not as easily identified.
¡ Bearings of stationary or slower moving
targets are more accurate than bearings
of faster moving targets.
¡ To minimize bearing errors keep echoes
in the outer half of the picture by chang-
ing the range scale; angular dif ference
becomes difficult to resolve as a target
approaches the center of the display.
2.13 Using the Offset EBL
The offset EBL provides two functions: pre-
dict collision course of a radar target and mea-
sure the range and the bearing between two
targets.
Predicting collision course
1. Operate the omnipad to place the cursor
on the center of the target.
2. Press the [EBL/VRM SELECT] key to
choose the EBL1 readout, and then press
the [EBL/VRM CONTROL] key.
3. Press the [MENU] key, select EBL OFF-
SET from the menu, and then press the
[ACQ/ENTER] key.
4. Press the [EBL/VRM CONTROL] key.
5. Oparate the omnipad so EBL1 passes
through the center of the target.
If the target tracks along the EBL towards the
center of the display (your vessel’s position),
the target may be on a collision course.
To cancel the of fset EBL, select EBL OFF-
SET from the menu and press the [ACQ/
ENTER] key.