Furuno FAR-2107(-BB) - Manual (Page 96)

1. RADAR OPERATION
1-74
1.38 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.
Second-trace
echo
Tx repetition
Actual range
False echo
range
Second-trace echoes
To reject second-trace echoes:
1. Left-click the MENU box to open the menu.
2. Select 1 [ECHO] to open the ECHO menu.
[ECHO]
1 BACK
2 2
ND ECHO REJ
OFF/ON
3 TUNE INITIALIZE
4 PM
OFF/ON
5 SART
OFF/ON
6 WIPER
OFF/1/2
7 ECHO AREA*
1
CIRCLE/WIDE/ALL
* 1 Not available on IMO or A type
8 [PICTURE SELECT]
9 STC RANGE
+00
ECHO menu
3. Select 2 2 ND ECHO REJ.
4. Select OFF or ON as appropriate.
5. Push the right button twice to close the menu.