Furuno FR-2805 Series - Manual (Page 33)

1-18
1.19 Measuring Range and
Bearing Between Two
Targets
Press the EBL OFFSET key, and place
the origin of No.1 EBL, for example, on a
target of interest (target 1 in the illustrated
example) by operating the trackball.
Turn the EBL control until the EBL passes
through another target of interest (target
2).
Turn the VRM control until the range
marker aligns with target 2. The active
VRM readout at the lower-right corner of
the screen indicates the distance between
the two targets.
You can repeat the same procedure on
third and forth targets (targets 3 and 4)
by using No.2 EBL and No.2 VRM.
Bearing is shown relative to own ship with
suffix "R" or as a true bearing with suffix
"T" depending on EBL relative/true set-
tings on the RADAR 2 menu. To return
the EBL origin to the own ship position,
press the EBL OFFSET key again.
000 010
020
030
040
050
060
070
080
090
100
110
120
130
140
150
160
170 180 190
200
210
220
230
240
250
260
270
280
290
300
310
320
330
340
350
EBL
origin
VRM
> 0.505NM<
0.985NM
EBL
> 140.0°R<
335.2°R
R1
R2
No.1 VRM
No.2 VRM
R2
Target 3
Target 4
Target 1
Target 2
Range
marker
No.1
EBL
No.2
EBL
Range
marker
Range/bearing
between targets
1 and 2
Range/bearing
between targets
3 and 4
1.20 Setting a Guard Zone
(Guard Alarm)
CAUTION
The guard zone (guard alarm) feature
should never be relied upon as the sole
means for detecting the risk of potential
collision. The operator of a ship is not
relieved of the responsibility to keep visual
lookout for avoiding collisions, whether or
not the radar is in use.
A guard zone (guard alarm) may be set
to alert the navigator to targets (ships,
landmasses, etc.) entering a certain area
with visual and audible alarms.
The guard zone (guard alarm) has a fixed
width of 0.5 nm in the radial direction and
is adjustable only within 3.0 to 6.0 nm from
own ship. The guard zone (guard alarm)
can be set to any sector angle between 0
and 360 degrees in any direction.
To set a guard zone (guard alram):
1. Place the cursor (+) at point "A" (see
figure at the top of the next page) us-
ing the trackball and press the GUARD
ALARM key on the mode panel (left key
group). The message SET GUARD
appears at the bottom-right corner of
the screen.
HL
OFF
ECHO
TRAILS
MODE
ORIGIN
MARK
VECTOR
TRUE/
REL
GUARD
ALARM
EBL
OFFSET
Inside mode panel
OFF
CENTER