Garmin nuvi 500-Series, Owner'S Manual

NOTE: 

You can optimize the radar display for each radar mode.

1

Select a radar range (

Range of Radar Signals

).

2

Restore the default value of the gain setting (

Adjusting Gain 

on the Radar Screen Automatically

).

3

Adjust the gain setting manually (

Adjusting Gain on the 

Radar Screen Manually

).

Radar Gain and Clutter

Adjusting Gain on the Radar Screen Automatically

The automatic gain setting for each radar mode is optimized for 

that mode, and 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.

NOTE: 

Not all options and settings are available on all radar 

and chartplotter models.

1

From a Radar screen or the Radar overlay, select 

Menu

 > 

Gain

.

2

Condition test. Home Screen not corrected.

3

Select an available option:
• Select 

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 adjust 

the gain automatically in response to changing conditions.

• Select 

Auto Harbor

 or 

Auto Offshore

.

The chartplotter automatically adjusts the gain for the 

conditions.

Adjusting Gain on the Radar Screen Manually

For optimal radar performance, you can manually adjust the 

gain.

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.

1

From a Radar screen or the Radar overlay, select 

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: 

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.

1

From a Radar screen or the Radar overlay, select 

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: 

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.

1

From a Radar screen or the Radar overlay, select 

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 Automatically

You can set the chartplotter to automatically adjust the 

appearance of clutter caused by choppy sea conditions.

NOTE: 

Depending upon the radar in use, the sea clutter setting 

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

applied to other radar modes or to the radar overlay.

NOTE: 

Not all options and settings are available on all radar 

and chartplotter models.

1

From a radar screen or the radar overlay, select 

Menu

 > 

Noise Rejection

 > 

Sea Clutter

.

2

Select 

Presets

 or 

Auto

.

3

Select a setting that reflects the present sea conditions.

When using a compatible radar model, the chartplotter adjusts 

the sea clutter based on the sea conditions automatically.

Adjusting Sea Clutter on the Radar Screen Manually

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 

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

applied to other radar modes or to the Radar overlay.

1

From a Radar screen or the Radar overlay, select 

Menu

 > 

Noise Rejection

 > 

Sea Clutter

.

2

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 (

Range 

of Radar Signals

).

The rain clutter setting affects the appearance of nearby rain 

clutter and targets more than it affects 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

From a Radar screen or the Radar overlay, select 

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.

20

Radar