2.14 Measuring the Range
You can measure the range to a target three ways: by the range rings, by the cursor, and by the VRM (Variable Range Marker).
Measuring range by range rings
Count the number of rings between the center of the display and the target. Check the range ring interval and judge the distance of the echo from the inner edge of the nearest ring.
To turn the rings on or off, see the menu opera- tion later (Chapter 3).
Measuring range by cursor
Operate the trackball to place the cursor inter- section on the inside edge of the target echo, The range to the target, as well as the bearing, appears at the bottom of the display.
Measuring by VRM
1.Press either [VRM 1] or [VRM 2] key. The readout of the active marker is circum- scribed.
EBL |
| VRM |
345.6°R |
| 5.3 NM |
23.0°R | 12.5 NM | |
Figure 2-8 Display bottom, showing location
of EBL and VRM readouts
2.Operate the trackball to place the outside edge of the VRM on the inside edge of the target. The trackball must be operated within five seconds after pressing a [VRM] key, oth- erwise the corresponding VRM cannot be operated. Press the [VRM] key again to ad- just the VRM.
3.Check the VRM readout at the bottom right- hand corner of the display to find the range to the target.
4.To anchor the VRM, press the [VRM] key again.
To erase the VRM, press and hold down the corresponding [VRM] key about two seconds.
Range
6.0 NM
Range ring 
2.0 interval
Target | VRM1 |
Cursor
VRM2
|
|
|
| VRM1 |
|
| VRM |
| range |
Cursor range |
| 4.0 NM |
|
|
| 4.0 NM 3.0 NM |
| VRM2 | |
|
| |||
|
|
|
| range |
Figure 2-9 Measuring range by the cursor
and VRM
Note: You can display the range readout of the VRM and cursor in nautical miles, statute miles or kilometers. For details see the next chapter.
2.15 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 trackball to bisect the target with the cursor intersection. The bearing to the tar- get appears at the bottom of the display.
Measuring by EBL
1.Press the [EBL 1] or [EBL 2] key.
2.Operate the trackball to bisect the target with the EBL.
The trackball must be operated within five seconds after pressing an [EBL] key, other- wise the corresponding EBL cannot be oper- ated. Press the [EBL] key again to adjust the EBL.
3.Check the EBL readout at the bottom left- hand corner of the display to find the bear- ing to the target.
4.To anchor the EBL, press the corresponding [EBL] key again.
To erase the EBL and its readout, press and hold down the corresponding [EBL] key about two seconds.