Furuno FR-8122 Noise Rejector, Suppressing Second-trace Echoes, How 2nd trace echoes are produced

1. OPERATIONAL OVERVIEW

1.31Noise Rejector

White noise may show itself on the screen as random "speckles" spread over the entire display. You can suppress this noise as follows:

1.Press the MENU key to show the menu.

2.Choose Echo and press the ENTER key.

3.Choose Noise Rejector and press the ENTER key.

Off

Low

Med

High

4.Choose Off, Low, Med or High as appropriate and press the ENTER key.

5.Press the MENU key to close the menu.

1.32Suppressing Second-trace Echoes

In certain situations, echoes from very distance targets may appear as false echoes (second-trace echoes) on the screen. This occurs when the return echo is received one transmission cycle later, or after a next radar pulse has been transmitted.

Tx repetition	Second-trace
	echo

False echo range

Actual range

How 2nd trace echoes are produced

1.Press the MENU key to show the menu.

2.Choose Echo and press the ENTER key.

3.Choose 2nd Echo Rejector and press the ENTER key.

4.Choose On or Off as appropriate and press the ENTER key.

5.Press the MENU key to close the menu.

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