Especially in inclement weather, longer-range radar signals can increase the clutter on the Radar screen and make it more difficult to view information about shorter-range targets. In rain, shorter-range radar signals can enable you to view information about nearby objects more effectively, if the rain clutter setting is configured optimally.

•Select the shortest effective range, given your reason for using radar and the present environmental conditions.

Zooming In and Out of the Radar Screen

•Pinch two fingers together to zoom out.

•Spread two fingers apart to zoom in.

•Drag the screen to pan, and then select or to zoom, if necessary.

Marking a Waypoint on the Radar Screen

1From a Radar screen or the Radar overlay, select a location.

2 Select Create Waypoint.

Sentry Mode

Sentry mode allows you to put the radar into timed-transmit mode, in which you can configure a radar transmit and standby cycle to conserve power. You can also enable a guard zone in this mode, which identifies a safe zone around your boat and sounds an alarm when a radar object enters the zone. Sentry mode works with all Garmin GMR model radars.

Enabling Timed Transmit

From the sentry screen, select Menu > Radar Menu > Sentry Setup > Timed Transmit > On.

Setting the Standby and Transmit Times

Before you can set the standby and transmit times, you must enable timed transmit (Enabling Timed Transmit).

To help conserve power, you can indicate the radar standby time and the transmit time to implement periodic radar signal transmissions at set intervals.

1From the sentry screen, select Menu > Radar Menu > Sentry Setup.

2Select Stdby Time.

3Enter the time interval between radar signal transmissions.

4 Select Transmit Time.

5 Enter the duration of each radar signal transmission.

Enabling a Guard Zone

From the sentry screen, select Menu > Radar Menu > Sentry Setup > Enable Guard Zone.

Defining a Circular Guard Zone

Before you can define the boundaries of the guard zone, you must enable a guard zone (Enabling a Guard Zone).

You can define a circular guard zone that completely encompasses your boat.

1From the sentry screen, select Menu > Radar Menu > Sentry Setup > Adjust Guard Zone > Adjust Guard Zone > Circle.

2Select the location of the outer guard zone circle.

3Select the location of the inner guard zone circle to define the width of the guard zone.

Defining a Partial Guard Zone

You can define the boundaries of a guard zone that does not completely encompass your boat.

1From the sentry screen, select Menu > Radar Menu > Sentry Setup > Adjust Guard Zone > Adjust Guard Zone > Corner 1.

2Touch and drag the location of the outer guard-zone corner

.

À

3Select Corner 2.

4 Touch the location of the inner guard-zone corner to

Á

define the width of the guard zone.

Radar Targeting and MARPA

Radar targeting enables you to identify and track objects.

Mini-automatic radar plotting aid (MARPA) is primarily used for collision avoidance. To use MARPA, you assign a MARPA tag to a target. The radar system automatically tracks the tagged object and provides you with information about the object, including the range, bearing, speed, GPS heading, nearest approach, and time to nearest approach. MARPA indicates the status of each tagged object (acquiring, lost, tracking, or dangerous), and the chartplotter can sound a collision alarm if the object enters your safe zone.

MARPA Targeting Symbols

Acquiring a target. Concentric, dashed green rings radiate from the target while the radar is locking onto it.

Target has been acquired. A solid green ring indicates the location of a target that the radar has locked onto. A dashed green line attached to the circle indicates the projected course over ground or the GPS heading of the target.

Dangerous target is in range. A red ring flashes from the target while an alarm sounds and a message banner appears. After the alarm has been acknowledged, a solid red dot with a dashed red line attached to it indicates the location and the projected course over ground or the GPS heading of the target. If the safe-zone collision alarm has been set to Off, the target flashes, but the audible alarm does not sound and the alarm banner does not appear.

Target has been lost. A solid green ring with an X through it indicates that the radar could not lock onto the target.

Closest point of approach and time to closest point of approach to a dangerous target.

Assigning a MARPA Tag to an Object

Before you can use MARPA, you must have a heading sensor connected and an active GPS signal. The heading sensor must provide the NMEA 2000 parameter group number (PGN) 127250 or the NMEA® 0183 HDM or HDG output sentence.

1From the Harbor, Offshore, or Cruising Radar screen, select an object or location.

2Select Acquire Target > MARPA Target.

Viewing Information about a MARPA-tagged Object

You can view the range, bearing, speed, and other information about a MARPA-tagged object.

1From a radar screen, select a targeted object.

2 Select MARPA Target.

Removing a MARPA Tag from a Targeted Object

1From the Radar screen, select a MARPA target.

2 Select MARPA Target > Remove.

Viewing a List of AIS and MARPA Threats

From any Radar screen or the Radar overlay, you can view and customize the appearance of a list of AIS and MARPA threats.

Radar

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