Garmin GPSMAP 702 Series Owner's Manual page 16

Symbol Description
Dangerous target is lost. A red X indicates that the AIS
transmission from the vessel is lost, and the chartplotter
displays a message banner asking whether the vessel should
continue to be tracked. If you discontinue vessel tracking, the
lost dangerous target symbol disappears from the chart or the
3D chart view.
The location of this symbol indicates the closest point of
approach to a dangerous target, and the numbers near the
symbol indicate the time to the closest point of approach to
that target.
NOTE: Vessels being tracked with the Blue Force Tracking
feature are indicated with a blue-green color regardless of their
status.
Heading and Projected Course of Activated AIS
Targets
When heading and course over ground information are provided
by an activated AIS target, the heading of the target appears on
a chart as a solid line attached to the AIS target symbol. A
heading line does not appear on a 3D chart view.
The projected course of an activated AIS target appears as a
dashed line on a chart or a 3D chart view. The length of the
projected course line is based on the value of the projected
heading setting. If an activated AIS target is not transmitting
speed information, or if the vessel is not moving, a projected
course line does not appear. Changes in the speed, course over
ground, or rate of turn information transmitted by the vessel can
impact the calculation of the projected course line.
When course over ground, heading, and rate of turn information
are provided by an activated AIS target, the projected course of
the target is calculated based on the course over ground and the
rate of turn information. The direction in which the target is
turning, which is also based on the rate of turn information, is
indicated by the direction of the barb at the end of the heading
line. The length of the barb does not change.
When course over ground and heading information are provided
by an activated AIS target, but rate of turn information is not
provided, the projected course of the target is calculated based
on the course over ground information.
Showing AIS and MARPA Vessels on a Chart or on a
3D Chart View
Before you can show AIS vessels on a chart, you must have an
external AIS device and active transponder signals from other
vessels. Mini Automatic Radar Plotting Aid (MARPA)
functionality works with radar.
You can configure how other vessels appear on a chart or on a
3D chart view. The display range and MARPA settings
configured for one chart or one 3D chart view are applied only to
that chart or to that 3D chart view. The details, projected
heading, and trails settings configured for one chart or one 3D
chart view are applied to all charts and to all 3D chart views.
1 From a chart or a 3D chart view, select Menu > Other
Vessels > Display Setup.
2 Select an option:
• To indicate the distance from your location in which AIS
vessels appear, select Display Range, and select a
distance.
• To show MARPA-tagged vessels, select MARPA > Show.
• To show details about AIS-activated and MARPA-tagged
vessels, select Details > Show.
8
• To set the projected heading time for AIS-activated and
MARPA-tagged vessels, select Proj. Heading, and enter
the time.
• To show the tracks of AIS vessels, select the length of the
track that appears using a trail, select Trails, and select
the length.
Activating a Target for an AIS Vessel
1
From a chart or a 3D chart view, select an AIS vessel.
2
Select AIS Vessel > Activate Target.
Viewing Information about a Targeted AIS Vessel
You can view the AIS signal status, MMSI, GPS speed, GPS
heading, and other information that is reported about a targeted
AIS vessel.
1
From a chart or a 3D chart view, select an AIS vessel.
2
Select AIS Vessel.
Deactivating a Target for an AIS Vessel
1
From a chart or a 3D chart view, select an AIS vessel.
2
Select AIS Vessel > Deactivate.
Viewing a List of AIS and MARPA Threats
1
From a chart or a 3D chart view, select Menu > Other
Vessels > List > Show.
2
Select the type of threats to include in the list.
Setting the Safe-Zone Collision Alarm
Before you can set a collision alarm, you must have a
compatible chartplotter connected to an AIS device or radar.
The safe-zone collision alarm is used only with AIS and MARPA.
MARPA functionality works with radar. The safe zone is used for
collision avoidance and can be customized.
1 Select Settings > Alarms > Collision Alarm > On.
A message banner appears and an alarm sounds when a
MARPA-tagged object or an AIS-activated vessel enters the
safe-zone area around your boat. The object is also labeled
as dangerous on the screen. When the alarm is off, the
message banner and audible alarm are disabled, but the
object is still labeled as dangerous on the screen.
2
Select Range.
3
Select a distance for the safe-zone radius around your
vessel.
4
Select Time To.
5
Select a time at which the alarm will sound if a target is
determined to intersect the safe zone.
For example, to be notified of a pending intersection 10
minutes before it will likely occur, set Time To to 10, and the
alarm will sound 10 minutes before the vessel intersects the
safe zone.
AIS Distress Signals
Self-contained AIS distress signal devices transmit emergency
position reports when activated. The chartplotter can receive
signals from Search and Rescue Transmitters (SART),
Emergency Position Indicating Radio Beacons (EPIRB), and
other man overboard signals. Distress signal transmissions are
different than standard AIS transmissions, so they appear
differently on the chartplotter. Instead of tracking a distress
signal transmission for collision avoidance, you track a distress
signal transmission to locate and assist a vessel or person.
Navigating to a Distress Signal Transmission
When you receive a distress signal transmission, a distress
signal alarm appears.
Select Review > Go To to begin navigation to the
transmission.
Charts and 3D Chart Views