Furuno FR-8252 EN - Manual (Page 56)

1. OPERATIONAL OVERVIEW
1-42
1.31 Noise 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.
4. Choose Off, Low, Med or High as appropriate and press the ENTER key.
5. Press the MENU key to close the menu.
1.32 Suppressing 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.
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.
Off
Low
Med
High
Second-trace
echo
Tx repetition
Actual range
False echo
range