Humminbird ONIX8 Installation Manual page 10

Observation: The best way to locate turbulence-free water is to view the transom while the boat is moving. This method is
recommended if maximum high-speed operation is a high priority. If this is not possible, select a location on the
transom where the hull forward of this location is smooth, flat, and free of protrusions or ribs.
Boat Characteristics
Stepped Hulls: On boats with stepped hulls, it may be possible to mount the transducer on the step. Do not mount the transducer on
the transom behind a step to avoid popping the transducer out of the water at higher speeds. The transducer must
remain in the water for the control head to maintain the sonar signal.
Trailering: If you plan to trailer your boat, do not mount the transducer too close to trailer bunks or rollers to avoid moving or
damaging the transducer during loading and unloading of the boat.
High-Speed Operation
DualBeam PLUS Transducer
Traveling over 65 mph with the transducer in the water is not recommended for the 200/50 kHz DualBeam PLUS transom mount
transducer (XNT 14 74 T), as damage might occur. If high-speed operation is critical, you may want to consider using an inside the hull
transducer instead of this transom mount transducer (see DualBeam PLUS Inside the Hull Installation).
Side Imaging Transducer
Side Imaging sonar is best performed at boat speeds from 2 to 6 mph, and is not recommended for high-speed operation as gaps
between strips of information can appear. However, the transducer can support traditional 2D sonar and Down Imaging sonar at higher
speeds (up to 65 mph).
NOTE: The Side Imaging transducer has additional mounting requirements. See the section Side Imaging Transducer Mounting
Requirements.
NOTE: If you require a high-speed application (above 65 mph) and cannot find a transom mount location that will work for your
boat hull, a different mounting technique or transducer type should be considered. See the FAQ (Frequently Asked Questions)
section of our Web site at humminbird.com or call Customer Service at 1-800-633-1468.
Deadrise
DualBeam PLUS Transducer
The hydrodynamic shape of your transducer allows the beam elements to point straight down
without deadrise adjustment.
Side Imaging Transducer
In order for the side beams to be displayed accurately, the transducer must be mounted parallel
with the waterline. This positioning allows the beam elements to point straight down without
deadrise adjustment.
Transom Transducer Installation 6
Deadrise
deadrise angle