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DualBeam PLUS™ Sonar
(DualBeam PLUS™ models only [688ci HD])
Your
688ci HD Fishfinder
uses a 200/83 kHz
DualBeam PLUS™ sonar system with a wide (60°)
area of coverage. DualBeam PLUS™ sonar has a
narrowly focused 20° center beam, surrounded by
a second beam of 60°, expanding your coverage
to an area equal to your depth. In 20 feet of
water, the wider beam covers an area 20 feet
wide.
DualBeam PLUS™ sonar returns can be blended
together, viewed separately, or compared side-
by-side. DualBeam PLUS™ is ideal for a wide
range of conditions - from shallow to very deep
water in both fresh and salt water. Depth
capability is affected by such factors as boat
speed, wave action, bottom hardness, water
conditions, and transducer installation.
How Sonar Works
