Dual Beam Sonar
The Dual Beam sonar fishfinders use a 200/455 kHz dual beam sonar system
with a 28° area of coverage. Dual Beam sonar is optimized to show the
greatest bottom definition using a narrow (16°) beam yet can still indicate fish
found in the wide (28°) beam when the Fish ID+ feature is turned on.
As the boat moves, the unit charts the changes in depth on the display to
create a profile of the Bottom Contour. The Sonar View displays the sonar
return intensity with a range of colors, where red indicates a strong return,
yellow indicates a medium return, and blue indicates a weak return.
strong returns
(possibly rocks,
tree limbs, or
other structure)
Strong returns often result from rocky or hard bottoms (compacted sediment,
rocks, fallen trees), while weaker returns often result from soft bottoms (sand,
mud), vegetation, and small fish.
Sonar Technology
Sonar View
Sonar History: historical returns
scroll left across the view.
2
weak returns
(possibly vegetation
or small fish)
strong return
(possibly compacted
sediment or rocks)