Using Radar

Reducing Unwanted Noise

There are several options that adjust the gain to help reduce unwanted clutter on the radar screen.

To reduce unwanted noise:

1.From the Radar screen, select Menu > Noise Rejection.

2.Select from the following options:

•Rain Cltr—adjust the gain for unwanted clutter caused by rain at close ranges. Select Up or Down to adjust the rain clutter sensitivity.

•Sea Cltr—adjust the gain for clutter caused by choppy sea conditions. Select Rough, Medium, or Calm. Select Up or Down to manually adjust the sea clutter sensitivity.

•Cross Talk—filter out interference caused by another radar operating in close proximity.

•FTC (Fast Time Constant)—reduce unwanted clutter caused by rain at a distance. FTC has four presets: Off, Low, Medium, or High.

Adjusting the VRM and EBL

The Variable Range Marker (VRM) and Electronic Bearing Line (EBL) tools measure range and bearing to a target. You can adjust the diameter of the VRM and the angle of the EBL.

To show or hide the VRM and EBL:

The measured range and bearing are displayed in the upper-left corner of the screen.

•If the VRM and EBL are hidden, from the Radar screen, select Menu > Show VRM/EBL.

•If the VRM and EBL are shown, from the Radar screen, select Menu > Adjust VRM/EBL > Hide VRM/EBL.

To select the VRM/EBL target location:

•(GPSMAP 4000 series) On the Radar screen, use the ROCKER to move the pointer to the VRM/EBL target location and select Drop VRM/EBL.

•(GPSMAP 5000 series) On the Radar screen, touch the target location and select Drop VRM/EBL.

To adjust the VRM/EBL target location:

1.From the Radar screen, select Menu > Adjust VRM/EBL > Move VRM/EBL.

2.Use the ROCKER to move the pointer (GPSMAP 4000 series) or touch the target location (GPSMAP 5000 series).

3.Press DONE to accept the changes.

Configuring Other Vessels on the Radar Screen

You can configure which other vessels are displayed on the radar screen, from the Radar screen, select Menu > Other Vessels.

NOTE: To configure AIS or DSC information for other boats, your unit must be connected to an external AIS or DSC device.

List—display a list of AIS and MARPA threats. Select Show to select between displaying AIS or MARPA threats, or All Threats.

DSC—turn DSC (Digital Selective Calling) trails on or off, configure how many hours a trail for a DSC vessel is displayed on the Radar screen, or display a list of tracked DSC vessels.

Collision Alarm (AIS and MARPA only)—turn a safe zone around your boat on or off. This is used for collision avoidance, and can be customized.

Using

Radar

GPSMAP® 4000/5000 Series Owner’s Manual

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