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Choosing a transducer is an important part of designing your sonar system. Here are the things to consider


Selecting your transducer

The sonar image on your display starts with the transducer, so its characteristics greatly affect the performance of the system. With so many different technologies, transducer selection may seem mystifying. The main points to consider are how will it be mounted, what views do I want and what frequencies do I need.

How will it be Mounted?

  • Most inland water boats are fitted with a transom or a shoot-thru-hull broadband sounder™ transducer as well as a second broadband sounder transducer on the bottom of the trolling motor, if equipped. Today, a transom mounted StructureScan HD® transducer can be found on most inland fishing boats.
  • Most bay/flats/offshore boats are fitted with a transom mount or a thru-hull transducer.

What views do I want?

  • Broadband and CHIRP can be accomplished with the same transducer—the difference is how the signal from the transducer is processed by the sonar module.
  • StructureScan HD requires a different style of transducer
  • SpotlightScan requires a dedicated transducer mounted to a foot-controlled trolling motor.

What Frequency do I need?

Here is a quick breakdown:

  • Low CHIRP or 50kHz—Lower frequency means higher power for deep-water fishing.
  • Medium CHIRP or 83kHz—Specifically designed to give the widest coverage area, 83 kHz is ideal for watching a bait under the transducer in shallow water.
  • High CHIRP or 200kHz—Higher frequencies display a higher resolution image making it easy to discern fish from structure or structure from the bottom.
  • 455kHz—Built into StructureScan HD and SpotlightScan, 455kHz allows for scanning of a large range with picture-like detail.
  • 800kHz—Also built into StructureScan HD and SpotlightScan, 800kHz yields less range but even higher resolution detail than 455kHz.