Transducers
Single Frequency
Knudsen Engineering can provide many different single frequency transducers. Ranging from 12 kHz- 200 kHz, most of our single frequency transducers are available with our optional aluminum mounting brackets for over-the-side mounting arrangements.
KEL291 Series Transducers

Designed for use in an IMO style housing, or a mounting can be fabricated to the customer's specifications. These multi-element arrays provide high transmitting and receiving voltage response for excellent target detection. Our low Q design gives good shallow water performance. This model is available with an underwater connector, allowing easy removal and replacement.
Models Available:
- KEL291 200 kHz
- KEL291 38 kHz
- KEL291 33 kHz
- KEL291 28 kHz
Also available for KEL291 Series:
- Transducer Housing
- Optional transducer mounting bracket for use in pole-mount applications.
KEL491 200 kHz Transducer

The KEL491 is designed for survey applications. It uses a PZT ceramic with an internal matching layer to achieve a low Q, low ring construction for both crisp echoes and excellent sensitivity. The 491 can be permanently mounted to a tank in a hull, in a towfish or adapted for portable mounting.
Models Available:
- KEL491 200 kHz
Also available for KEL491 Series:
- Optional transducer mounting bracket for use in pole-mount applications.
KEL571 12 kHz Transducer

This single 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 kHz
KEL922 12 kHz Transducer
Designed for use on steel hulled vessels where a very high strength and easy to service transducer is required. This large cast steel model is comprised of the inner housing and outer through-hull housing.
Models Available:
- KEL922 12 kHz