NorthStar EXPLORER 443S Installation And Operation Manual page 12

Shadows
Shadows are areas where the ultrasonic beam cannot 'see'. These include
hollows on the bottom or beside rocks and ledges where the strong
echo returned off the rock obscures the weaker echo of the fish.
When looking for small objects including fish, users should consider that
there are places where fishfinders cannot 'see'.
Shadow - where objects are hidden in the bottom echo.
These fish will be hidden in the bottom echo.
Northstar fishfinders display the most recent events on the right of the screen.
Moving boat
1 minute ago
Air in water
(e.g. from
wake)
12
30 seconds ago
Northstar Explorer 443s/443sp Installation and Operation Manual
Now
When the fish symbol option is
ON, any echo returned that fits
the profile of a fish is displayed
on the screen with a fish symbol.