Furuno 1942 MARK-2 manual Measuring the Bearing, Using the Offset EBL

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).

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.

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				Target
					Cursor
					EBL1
					EBL2
					Cursor
			EBL		bearing
EBL1 bearing
			40.0° R
EBL1 bearing			135.0° R	40.0°R 4.0 NM

Figure 2-8 How to measure bearing by EBL

and cursor

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 difference 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 offset EBL, select EBL OFF- SET from the menu and press the [ACQ/ ENTER] key.

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