Measuring The Range; Measuring The Bearing - Furuno 821 Operator's Manual

2.10 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).
By range rings
Press the [RINGS] key to display the range
rings. Count the number of rings between
the center of the display and the target.
Check the range ring interval (at the top left
corner) and judge the distance of the echo
from the inner edge of the nearest ring.
By cursor
Operate the cursor pad to place the cursor
intersection on the inside edge of the target
echo. The range to the target, as well as the
bearing, appears at the bottom of the dis-
play.
By VRM
1) Press the [VRM] key to display the VRM.
2) Press the cursor pad to place the VRM
on the inside edge of the target. (The cur-
sor appears and is linked with the VRM,
allowing you to measure both range and
bearing to the target.)
3) Check the VRM readout at the bottom
left-hand corner of the display to find the
range to the target.
Note: The VRM is automatically anchored
when no cursor pad key is operated within
about 10 seconds.
To erase the VRM, press and hold down
the [VRM] key for about three seconds.
8
1.5
NM
0.5
Target
VRM
VRM
VRM
0.675 220.9°
NM
range
Figure 2-8 Measuring range by the VRM

2.11 Measuring the Bearing

There are two ways to measure the bearing
to a target: by the cursor, and by the EBL
(Electronic Bearing Line).
By cursor
Operate the cursor pad to bisect the target
with the cursor intersection. The bearing to
the target appears at the bottom right-hand
corner of the display.
By EBL
1) Press the [EBL] key to display the EBL.
2) Press the cursor pad to bisect the target
with the EBL. (The cursor appears and is
linked with the EBL, allowing you to
measure both bearing and range to the
target.)
3) Check the EBL readout at the bottom left-
hand corner of the display to find the bear-
ing to the target.
Note: The EBL is automatically anchored when
no cursor pad key is operated within about 10
seconds.
EBL + CURSOR
0.675 308.7°
R NM R