Furuno 1761 MARK-3 - Manual (Page 16)

2-5
2.13 Select the Cursor Data
Display
When connecting with NAV (IEC61162 for-
mat) and gyro converter (IEC61162 or AD-
10 format), this radar can show the cursor
position by Latitude/longitude at bottom of
screen.
Each time pressing [HM OFF] key, the data
will change from Range/Bearing to Latitude/
longitude and vice versa.
When the cursor position is displayed by Lati-
tude/Longitude, pressing the [HM OFF] key
outputs L/L data of the cursor position (TLL)
to the plotter. Then Range/Bearing are dis-
played instead of L/L.
2.14 Turning the Range Ring
On/Off
When range rings obscures a target, you can
erase them by pressing the [RING] key.
2.15 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 cen-
ter 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, press the [RING]
key.
Measuring range by cursor
Operator the trackball to place the cursor in-
tersection 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 the [VRM] key to display a VRM.
(The VRM is the dotted ring.)
2. Place the VRM on the inside edge of the
target by operating the trackball.
3. Press the [VRM] key again to fix the VRM
to the position.
4. Check the range readout to find the range
to the target. To erase the VRM, press
and hold down the [VRM] key for about
three seconds.
VRM
6.0 NM
2.0
Range
Range ring
interval
Target
Cursor
Cursor range
315.1°R
4.0 NM VRM
4.0 NM VRM
range
Figure 2-5 Measuring Range by the Cursor
and the VRM
Unit of range measurement
You can display the range readouts of the
VRM and the cursor in nautical miles or kilo-
meters. This is done at installation.
2.16 Measuring the Bearing
There are two ways to measure the bearing
to a target: by the cursor, and by the EBL
(Electronic Bearing Range).
Measuring bearing by cursor
Operate the trackball to bisect the target with
the cursor intersection. The bearing to the
target appears at the bottom of the display.
Measuring by EBL
1. Press the [EBL] key to display an EBL.
(The EBL is the dotted line.)