Garmin GPSMAP 721 Owner's Manual - Page 23

may differ from the automatic gain setting used for another

mode.

NOTE:

Depending upon the radar in use, the gain setting

configured for use in one radar mode may or may not be

applied to other radar modes or to the Radar overlay.

From a Radar screen or the Radar overlay, select

Menu

>

Gain

>

Auto

.

The chartplotter sets the gain automatically once, based on

average conditions, the range of the radar signal, and the

selected radar mode. The chartplotter does not readjust the

gain automatically in response to changing conditions.

Manually Adjusting Gain on the Radar Screen

For optimal radar performance that accounts for actual

conditions, you can manually adjust the gain.

NOTE:




1


Menu

>

Gain

.

2

Select

Up

to raise the gain, until light speckles appear across

the Radar screen.

Data on the Radar screen is refreshed every few seconds.

As a result, the effects of manually adjusting the gain may

not appear instantly. Adjust the gain slowly.

3

Select

Down

to lower the gain until the speckles disappear.

4

If boats, land, or other targets are within range, select

Down

to lower the gain until the targets begin to blink.

5

Select

Up

to raise the gain until the boats, land, or other

targets appear steadily lit on the Radar screen.

6

Minimize the appearance of nearby large objects, if

necessary.

7

Minimize the appearance of side-lobe echoes, if necessary.

Minimizing Nearby Large-Object Interference

Nearby targets of significant size, such as jetty walls, can cause

a very bright image of the target to appear on the Radar screen.

This image can obscure smaller targets located near it.

NOTE:




1


Menu

>

Gain

.

2

Select

Down

to lower the gain until the smaller targets are

clearly visible on the Radar screen.

Reducing the gain to eliminate nearby large-object

interference may cause smaller or distant targets to blink or

disappear from the Radar screen.

Minimizing Side-Lobe Interference on the Radar Screen

Side-lobe interference may appear to streak outward from a

target in a semi-circular pattern. Side-lobe effects can be

avoided by reducing the gain or reducing the radar range.

NOTE:




1


Menu

>

Gain

.

2

Select

Down

to lower the gain until the semi-circular,

streaked pattern disappears from the Radar screen.

Reducing the gain to eliminate side-lobe interference may

cause smaller or distant targets to blink or disappear from

the Radar screen.

Adjusting Sea Clutter on the Radar Screen

You can adjust the appearance of clutter caused by choppy sea

conditions. The sea clutter setting affects the appearance of

nearby clutter and targets more than it affects the appearance

of distant clutter and targets. A higher sea clutter setting

reduces the appearance of clutter caused by nearby waves, but

it can also reduce or eliminate the appearance of nearby

targets.

NOTE:

Depending upon the radar in use, the sea clutter setting



1


Menu

>

Noise Rejection

>

Sea Clutter

>

Presets

.

2

Select a setting that reflects the present sea conditions.

3

Select

Menu

>

Noise Rejection

>

Sea Clutter

.

4

Select

Up

or

Down

to adjust the appearance of sea clutter

until other targets are clearly visible on the Radar screen.

Clutter caused by sea conditions may still be visible.

Adjusting Rain Clutter on the Radar Screen

You can adjust the appearance of clutter caused by rain.

Reducing the radar range also can minimize rain clutter

(

page 15

).

The rain clutter setting effects the appearance of nearby rain

clutter and targets more than it effects the appearance of distant

rain clutter and targets. A higher rain clutter setting reduces the

appearance of clutter caused by nearby rain, but it can also

reduce or eliminate the appearance of nearby targets.

NOTE:

Depending upon the radar in use, the rain clutter

settings configured for use in one radar mode may or may not

be applied to other radar modes or to the Radar overlay.

1


Menu

>

Noise Rejection

>

Rain Clutter

.

2

Select

Up

or

Down

to decrease or increase the appearance

of nearby rain clutter until other targets are clearly visible on

the Radar screen.

Clutter caused by rain may still be visible.

Reducing Cross Talk Clutter on the Radar Screen

You can reduce the appearance of clutter caused by

interference from another nearby radar source, when the Cross

Talk Reject setting is on.

NOTE:

Depending upon the radar in use, the crosstalk setting




Menu

>

Noise Rejection

>

Cross Talk Reject

.

Radar Display Settings

From any Radar screen or the Radar overlay, select

Menu

>

Radar Setup

.

Orientation

: Sets the perspective of the radar display. The

orientation setting applies to every radar mode. This setting

does not apply to the Radar overlay.

Appearance

: Sets the color scheme, look-ahead speed, and

navigation appearance.

Front of Boat

: Compensates for the physical location of the

radar scanner on a boat, if the radar scanner does not align

with the bow-stern axis.

Radar Appearance Settings

From a Radar screen, select

Menu

>

Radar Setup

>

Appearance

.

NOTE:

These settings do not apply to the Radar overlay.

Color Scheme

: Sets the color scheme.

Look-Ahead Speed

: Shifts your present location toward the

bottom of the screen automatically as your speed increases.

Enter your top speed for the best results.

Heading Line

: Shows an extension from the bow of the boat in

the direction of travel on the radar screen.

Radar

17

Garmin GPSMAP 721 Owner's Manual - Page 23

Radar Display Settings, Radar Appearance Settings

Page 23 highlights

Section	Page
Table of Contents	3
Introduction	7
Device Views	7
echoMAP 70 Series and GPSMAP 700 Series	7
Using the Touchscreen	7
Locking the Touchscreen	7
echoMAP 50 Series and GPSMAP 500 Series	7
Device Keys	7
Tips and Shortcuts	7
GPS Satellite Signals	7
Adjusting the Backlight	7
Adjusting the Color Mode	7
Customizing the Home Screen	7
Inserting Memory Cards	7
Charts and 3D Chart Views	8
Navigation Chart and Offshore Fishing Chart	8
Zooming In and Out of the Chart	8
Panning the Chart	8
Selecting an Item on the Map Using the Device Keys	8
Chart Symbols	8
Navigating to a Point on the Chart	8
Viewing Location and Object Information on a Chart	9
Viewing Details about Navaids	9
Premium Charts	9
Viewing Tide Station Information	9
Animated Tide and Current Indicators	9
Showing and Configuring Tides and Currents	10
Showing Satellite Imagery on the Navigation Chart	10
Viewing Aerial Photos of Landmarks	10
Automatic Identification System	10
AIS Targeting Symbols	10
Heading and Projected Course of Activated AIS Targets	10
Showing AIS Vessels on a Chart or 3D Chart View	11
Activating a Target for an AIS Vessel	11
Viewing Information about a Targeted AIS Vessel	11
Deactivating a Target for an AIS Vessel	11
Viewing a List of AIS Threats	11
Setting the Safe-Zone Collision Alarm	11
AIS Distress Signals	11
Navigating to a Distress Signal Transmission	11
AIS Distress Signal Device Targeting Symbols	11
Enabling AIS Transmission Test Alerts	11
Turning Off AIS Reception	11
Chart and 3D Chart View Settings	11
Navigation and Fishing Chart Setup	12
Waypoints and Tracks Settings on the Charts and Chart Views	12
Overlay Numbers Settings	12
Editing the Data Fields	12
Showing a Navigation Inset	12
Chart Appearance Settings	12
Other Vessels Settings on the Charts and Chart Views	13
AIS Display Settings	13
Fish Eye 3D Settings	13
Navigation with a Chartplotter	13
Basic Navigation Questions	13
Destinations	13
Searching for a Destination by Name	13
Selecting a Destination Using the Navigation Chart	13
Searching for a Destination Using Nav Info	13
Searching for a Marine Services Destination	13
Courses	14
Setting and Following a Direct Course Using Go To	14
Setting and Following a Course Using Auto Guidance	14
Autopilot Navigation	14
Stopping Navigation	14
Waypoints	14
Marking Your Present Location as a Waypoint	14
Creating a Waypoint at a Different Location	14
Marking and Navigating to an MOB Location	14
Viewing a List of all Waypoints	14
Editing a Saved Waypoint	14
Moving a Saved Waypoint	14
Browsing for and Navigating to a Saved Waypoint	14
Deleting a Waypoint or an MOB	15
Deleting All Waypoints	15
Routes	15
Creating and Navigating a Route From Your Present Location	15
Creating and Saving a Route	15
Viewing a List of Routes	15
Editing a Saved Route	15
Browsing for and Navigating a Saved Route	15
Browsing for and Navigating Parallel to a Saved Route	15
Deleting a Saved Route	16
Deleting All Saved Routes	16
Tracks	16
Showing Tracks	16
Setting the Color of the Active Track	16
Saving the Active Track	16
Viewing a List of Saved Tracks	16
Editing a Saved Track	16
Saving a Track as a Route	16
Browsing for and Navigating a Recorded Track	16
Deleting a Saved Track	16
Deleting All Saved Tracks	16
Retracing the Active Track	16
Clearing the Active Track	16
Managing the Track Log Memory During Recording	16
Configuring the Recording Interval of the Track Log	16
Deleting All Saved Waypoints, Routes, and Tracks	17
Combinations	17
Selecting a Combination	17
Customizing the Combinations Screen	17
Gauges and Almanac Information	17
Viewing the Compass	17
Viewing Trip Gauges	17
Resetting Trip Gauges	17
Viewing Engine and Fuel Gauges	17
Customizing Engine Gauge and Fuel Gauge Limits	17
Enabling Status Alarms for Engine Gauges	17
Enabling Some Engine Gauge Status Alarms	17
Selecting the Number of Engines Shown in Gauges	17
Customizing the Engines Shown in Gauges	17
Configuring the Fuel Gauges Display	17
Setting the Fuel Capacity of the Vessel	18
Synchronizing the Fuel Data with the Actual Vessel Fuel	18
Setting the Fuel Alarm	18
Viewing the Wind Gauges	18
Configuring the Speed Source	18
Configuring the Heading Source of the Wind Gauge	18
Selecting the Range of the Close-Hauled Wind Gauge	18
Viewing the Environment Gauges	18
Configuring the Alignment of the Wind Gauge	18
Configuring the Heading Source of the Environment Gauge	18
Setting the Barometer Reference Time	18
Tide, Current, and Celestial Information	18
Tide Station Information	18
Current Station Information	18
Celestial Information	18
Viewing Tide Station, Current Station, or Celestial Information for a Different Date	19
Viewing Information for a Different Tide or Current Station	19
Viewing Almanac Information from the Navigation Chart	19
Sonar	19
Full-Screen Sonar View	19
Split-Zoom Sonar View	19
Split-Frequency Sonar View	19
Pausing the Sonar Display	19
Creating a Waypoint on the Sonar Screen	19
Adjusting the Gain on the Sonar Screen	19
Adjusting the Range of the Depth Scale	19
Setting the Zoom Level on the Sonar Screen	19
Selecting Frequencies	19
Turning On the A-Scope	20
Sonar Setup	20
Sonar Settings	20
Sonar Appearance Settings	20
Advanced Sonar Settings	20
Sonar Alarm Settings	20
Recording the Sonar Display	20
Stopping the Sonar Recording	20
Depth and Water Temperature Graphs	20
Setting the Depth and Water Temperature Graph Range and Time Scales	20
Radar	20
Radar Display Modes	21
Transmitting Radar Signals	21
Adjusting the Zoom Scale on the Radar Screen	21
Tips for Selecting a Radar Zoom Scale	21
Sentry Mode	21
Enabling Timed Transmit	21
Setting the Standby and Transmit Times	21
Enabling a Guard Zone	21
Defining a Circular Guard Zone	21
Defining a Partial Guard Zone	21
Marking a Waypoint on the Radar Screen	22
Viewing a List of AIS Threats	22
Showing AIS Vessels on the Radar Screen	22
VRM and EBL	22
Showing the VRM and the EBL	22
Adjusting the VRM and the EBL	22
Measuring the Range and Bearing to a Target Object	22
Radar Overlay	22
Radar Overlay and Chart Data Alignment	22
Showing the Radar Overlay	22
Stopping the Transmission of Radar Signals	22
Optimizing the Radar Display	22
Range of Radar Signals	22
Radar Gain and Clutter	22
Automatically Adjusting Gain on the Radar Screen	22
Manually Adjusting Gain on the Radar Screen	23
Minimizing Nearby Large-Object Interference	23
Minimizing Side-Lobe Interference on the Radar Screen	23
Adjusting Sea Clutter on the Radar Screen	23
Adjusting Rain Clutter on the Radar Screen	23
Reducing Cross Talk Clutter on the Radar Screen	23
Radar Display Settings	23
Radar Appearance Settings	23
Front-of-Boat Offset	24
Measuring the Potential Front-of-Boat Offset	24
Setting the Front-of-Boat Offset	24
Digital Selective Calling	24
Networked Chartplotter and VHF Radio Functionality	24
Turning On DSC	24
DSC List	24
Viewing the DSC List	24
Adding a DSC Contact	24
Incoming Distress Calls	24
Navigating to a Vessel in Distress	24
Man-Overboard Distress Calls Initiated from a VHF Radio	24
Man-Overboard Distress Calls Initiated from the Chartplotter	24
Position Tracking	24
Viewing a Position Report	24
Navigating to a Tracked Vessel	25
Creating a Waypoint at the Position of a Tracked Vessel	25
Editing Information in a Position Report	25
Deleting a Position-Report Call	25
Viewing Vessel Trails on the Chart	25
Individual Routine Calls	25
Selecting a DSC Channel	25
Making an Individual Routine Call	25
Making an Individual Routine Call to an AIS Target	25
Viewing Video	25
Configuring the Video Appearance	25
SiriusXM™	25
SiriusXM Equipment and Subscription Requirements	26
Weather Data Broadcasts	26
Viewing Precipitation Information	26
Precipitation Views	26
Storm Cell and Lightning Information	26
Hurricane Information	26
Weather Warnings and Weather Bulletins	26
Forecast Information	26
Viewing Forecast Information for Another Time Period	26
Viewing a Marine Forecast or an Offshore Forecast	27
Weather Fronts and Pressure Centers	27
City Forecasts	27
Viewing Sea Conditions	27
Surface Winds	27
Wave Height, Wave Period, and Wave Direction	27
Viewing Forecast Sea Conditions Information for Another Time Period	27
Viewing Fishing Information	27
Surface Pressure and Water Temperature Data	27
Forecasting Fish Locations	27
Visibility Information	27
Viewing Forecast Visibility Information for Another Time Period	28
Viewing Buoy Reports	28
Viewing Local Weather Information near a Buoy	28
Creating a Waypoint on a Weather Chart	28
Weather Overlay	28
Turning On the Weather Overlay on a Chart	28
Weather Overlay Settings on the Navigation Chart	28
Weather Overlay Settings on the Fishing Chart	28
Viewing Weather Subscription Information	28
SiriusXM Radio	28
Customizing the Channel Guide	28
Saving a SiriusXM Channel to the Presets List	28
Adjusting SiriusXM Satellite Radio Volume	28
Device Configuration	28
Turning On the Chartplotter Automatically	28
System Settings	29
GPS Settings	29
Viewing the Event Log	29
Viewing System Software Information	29
My Vessel Settings	29
Setting the Keel Offset	29
Calibrating a Water Speed Device	29
Setting the Water Temperature Offset	30
Communications Settings	30
NMEA 2000 and NMEA 0183	30
NMEA 0183	30
NMEA 0183 Settings	30
NMEA 2000	30
Viewing a List of NMEA 2000 Network Devices	30
Communication with Wireless Devices	30
Connecting a Bluetooth Wireless Device	30
Disconnecting a Bluetooth Wireless Device	30
Setting Up the Wireless Network	30
Connecting a Wireless Device to the Chartplotter	31
Setting Alarms	31
Navigation Alarms	31
System Alarms	31
Setting the Fuel Alarm	31
Setting Weather Alarms	31
Units Settings	31
Navigation Settings	31
Auto Guidance Line Configurations	31
Adjusting the Distance from Shore	32
Other Vessel Settings	32
Viewing System Software Information	32
Restoring the Original Chartplotter Factory Settings	32
Chartplotter Data Management	32
Copying Waypoints, Routes, and Tracks to a Chartplotter	32
Copying Data from a Memory Card	32
Copying Waypoints, Routes, and Tracks to a Memory Card	32
Copying Waypoints, Routes, and Tracks to or from all Chartplotters on a NMEA 2000 Network	33
Copying Built-In Maps to a Memory Card	33
Backing Up Data to a Computer	33
Restoring Backup Data to a Chartplotter	33
Saving System Information to a Memory Card	33
Appendix	33
Registering Your Device	33
Calibrating the Touchscreen	33
Updating the Device Software	33
Screenshots	33
Capturing Screenshots	33
Copying Screenshots to a Computer	33
NMEA 0183 Information	33
NMEA 2000 PGN Information	34