Transducers
Dual Frequency
Knudsen Engineering can provide many different dual frequency transducers. Ranging from 12 kHz- 200 kHz, most of our dual frequency transducers are available with our optional aluminum mounting brackets for over-the-side mounting arrangements.
KEL361 Series Transducers
Several of the more the popular frequencies - 33kHz and 200 or 210 kHz, are included in the KEL361 Sealcast housing. 33kHz is generated by a single seven-element ceramic array with exceptional performance provided. The conical beam patterns with minimal side lobes allow the user to perform accurate marine survey in both shallow and deep water.
Models Available:
- KEL361 33/200 kHz
- KEL361 33/210 kHz
KEL771 28/200 kHz Transducer

Two popular frequencies - 28 kHz and 200 kHz, are included in the KEL771 Sealcast housing. 28 kHz is generated by a seven-element ceramic array providing exceptional performance. The 200 kHz frequency is generated by a single large diameter ceramic.
Models Available:
- KEL771 28/200 kHz
Also available for KEL771 Series:
- Optional transducer mounting bracket for use in pole-mount applications.
KEL571 12/200 kHz Transducer

This dual frequency transducer will provide high definition echoes and good discrimination of targets in deep water. The urethane casting compound is an excellent transmitter of ultrasound, is highly resistant to cuts and abrasion, and has excellent impact resistance. This transducer is designed for tank mounting, external mount or portable mount.
Models Available:
- KEL571 12 /200 kHz
KEL551 50/200 kHz Transducer
The seven-piezoceramic element provides superlative sensitivity and very low ringing at 50 kHz for crisp, high intensity echoes. The streamline shape of the housing reduces drag.
Models Available:
- KEL551 50/200 kHz
Also available for KEL551 Series:
- Optional transducer mounting bracket for use in pole-mount applications.