Down Imaging™ Sonar (858C Di And 958C Di Only, Xnt 9 Di T); Quadrabeam Plus™ Sonar; [858C, 958C, 898C Si, And 998C Si Only]) - Humminbird 858c Combo Operation Manual

45°
800kHz
75°
455kHz
16°
455kHz
25°
200kHz
75 Degree Total Coverage
Introduction
Down Imaging™ Sonar
(858c DI and 958c DI only, XNT 9 DI T)
Your 858c DI/958c DI Fishing System uses
Down Imaging™ technology. The Down
Imaging™ transducer scans the water
with razor-thin, high-definition beams.
The beams are wide (side to side) but very
thin front to back.
The Down Imaging™ beams can be
operated at two frequencies: 455 kHz
(75°) or 800 kHz (45°). Select 455 kHz for
the best overall image quality and depth.
Select 800 kHz for the sharpest image.
See Down Imaging™ X-Press™ Menu:
Imaging Frequency for more information.
The transducer also uses conical beams to
provide data in traditional 2D format (see
What's on the Sonar View). Select 455
kHz for a narrowly focused 16° center
beam, or select 200 kHz for a wider 25°
beam (see Sonar Menu Tab: Beam
Select).
Depth capability is affected by such
factors as boat speed, wave action,
bottom hardness, water conditions, and
transducer installation.
35° 60° 20° 35°
455 kHz
200 kHz
83 kHz
90° Total Coverage
Bottom Coverage = 2 x Depth
4
QuadraBeam PLUS™ Sonar
(optional-purchase QuadraBeam PLUS™
transducer only [858c, 958c, 898c SI, and
998c SI only])
Your Fishing System supports the
optional-purchase QuadraBeam PLUS™
455 kHz
transducer. QuadraBeam PLUS™ sonar
provides a wide (90°) area of coverage.
QuadraBeam PLUS™ starts with two
fan-shaped 35° 455 kHz Side Structure
locating sonar beams to spot fish, bait,
and structure to the left and right of the
boat over an area of the bottom that's
always equal to twice your depth.
For a detailed view below the boat,
QuadraBeam PLUS™ uses DualBeam
PLUS™ technology, with precision 20°
and wide 60° beams. QuadraBeam
PLUS™ finds more fish faster, and can
even tell you where to put your bait by
showing if fish are to the left, right, or
directly beneath your boat.