Earlier this year, offshore tournament anglers using a Garmin fish finder held a solid bottom reading en route to Bermuda: 17,624 feet. Yes, a transducer was able to get and maintain a reading from three miles below the surface. (Read the full story here on Ben Ellison’s Panbo blog.) This was made possible thanks to the CHIRP transducer technology from Airmar. Here’s how it is changing the game.
Traditional marine fish finders operate by transmitting two fixed frequencies: 200 kHz, a short high-energy wave for shallow water; and 50 kHz, a long low-energy wave for deep water. The traditional transducer houses one broadband ceramic to produce these fixed frequencies, which are shorter in duration with a narrower band.
Airmar brought CHIRP to market last year, importing military technology, which was being used as far back as World War II, into the recreational marine market. Airmar worked with companies such as Navico (Simrad and Lowrance), Raymarine and Garmin to develop black-box sonar units to work with their fish finders.