Furuno SFD-1010 Operator's Manual page 207

9. Press the MENU/ESC key to close [MENU].
Note: You cannot set the start bearing and the end bearing when [Sect-Blank 1 Status]
or [Sect-Blank 2 Status] is set to [Off].
Sect-Blank 1 Status
Sect-Blank 2 Status
Sector blank area
Set [Sect-Blank 1 Status] or [Sect-Blank 2 Status] to [On], to show set sector blank on
the screen (with a line).
[On]
[On]
5. INSTALLATION
Sect-Blank 1 Status
Sect-Blank 2 Status
[Off]
[Off]
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