MARPA options
The MARPA options are accessible by pressing the TARGET
TRACKING > MARPA & AIS OPTIONS softkeys.
Parameter Descriptions Options
Vector Length The time period
specied for drawing
length of vectors.
• 0.5 min
• 1 min
• 3 min
• 6 min
• 12 min
• 30 min
• 60 min
Target History Plots a target’s previous
position at specied
intervals. The four
most recent position
points are displayed.
If True target vectors
are selected, the four
most recent vessel
position points are also
displayed.
• OFF
• 0.5 min
• 1 min
• 3 min
• 6 min
Own Vessel Safe Zone The safe zone is a ring,
centred on your boat,
within which a target is
considered dangerous
if it will enter this zone
within the Time to Safe
Zone period (see below).
• 0.1 nm
• 0.2 nm
• 0.5 nm
• 1.0 nm
• 2.0 nm
Parameter Descriptions Options
Time to Safe Zone If a target enters your
safe zone within this time
period, it is considered
dangerous.
• 3 min
• 6 min
• 12 min
• 24 min
Safe Zone Ring Controls whether the
safe zone ring is
displayed or hidden
on screen.
• Visible
• Hidden
Using MARPA
Acquiring a MARPA target to track
In the radar application:
1. Select the TARGET TRACKING softkey.
2. Move the cursor over the target to be acquired.
3. Select the ACQUIRE TARGET softkey.
The “target being acquired” symbol is displayed. If the target is
present for several scans, the radar locks-on to the target, and the
symbol changes to “safe target” status.
Cancelling a MARPA target
In the radar application:
1. Move the cursor over the relevant target.
2. Press the CANCEL TARGET softkey.
3. Alternatively, display the MARPA target list by pressing the
TARGET TRACKING, then MARPA LIST softkeys.
4. Using the trackpad, select the relevant MARPA target from the
list.
5. Press the CANCEL TARGET softkey.
Using radar
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