1. RADAR OPERATION
1-39
1.23 Target
Alarm
The target alarm serves to alert the navigator to targets (ships, landmasses, etc.)
entering a specific area, with audiovisual alarms.
CAUTION
•
The alarm should not be relied upon as
the sole means for detecting possible
collision situations.
•
A/C SEA, A/C RAIN and GAIN controls
should be properly adjusted to be sure
the alarm system does not overlook
target echoes.
The target alarm zone has a fixed width of 0.5 nm in the radial direction (depth)
and is adjustable from 3.0 to 6.0 nm (guard zone 1) and any distance (guard
zone 2). On the Non-IMO radar the boundaries can be set at any distance. On
any radar type the sector of the zone can be set from 0 to 360 degrees in any
direction.
1.23.1
How to set a target alarm
The procedure below shows how to set a target alarm using the figure below as
an example.
1. Left-click ALARM1 or ALARM2 box, whichever alarm you wish to put the
cursor jumps into the effective display area and "SET" appears inside the
ALARM box selected.
ALARM 1
ALARM 2
ALARM boxes
2. Use the trackball to put the cursor on point "A" then push the left button.
3. Use the trackball to put the cursor on point "B" then push the left button.
"WORK" replaces "SET" in the ALARM box. The target alarm zone’s lines are
shown in dashed lines.
000
010 020
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Target alarm zone
A
B
X
X
Point A
X
X
X
X
Point B
Point B
Point B
Point A
Point A
Other alarm zone examples
Target alarm zone
