SIMRAD BSM-2 & CHIRP Revolution

Imagine knowing what exact frequencies work the best at detecting specific fish species: Bluefin Tuna—60 kHz and Squid—133 kHz. Now imagine tuning your fishfinder to these frequencies, marking the fish precisely on the screen, then catching them! CH Smith Marine is proud to announce that with the B265LH transducer connected to a Simrad NSS or NSE Multifunction Displays and BSM2 Broadband Sounder Module, you too can have a log book like a commercial fisherman! This powerhouse transducer delivers extreme target detail, bottom discrimination, and bait and game fish separation at all depths.

Simrad's BSM-2 Broadband Sounder Module , coupled with Airmar's Broadband Chirp Transducers represent the next generation of technology that will allow fishermen to unlock new secrets in fishfinding.

CHIRP Fishfinders transmit across a wide frequency band instead of using a single frequency. This is also known as “Frequency Modulation” or “Spread-Spectrum” Transmissions. These waveforms are typically of long duration and for example may start at 42 kHz and end at 65 kHz. Energy transmitted into the water can be 10 to 50 times greater than a traditional fishfinder. By storing the shape of the transmitted waveform in memory and comparing it to the received echoes using pattern matching techniques (also called pulse compression), it is possible to find targets within the noise and precisely determine their range with astounding accuracy.

So instead of firing a 50 kHz or 200 kHz pulse beneath the boat to bounce off things and return at the same frequency, CHIRP technology modulates the pulse so the ping sent by the transducer sweeps across a range of frequencies, say 28 kHz to 60 kHz, or 130 kHz to 210 kHz, or 42 kHz to 65 kHz. The return or bounce-back off a target reflects the frequency at which the target was struck, so even two targets close together are going to return the ping at different frequencies. The result is improved separation and detail enabling the distinction of a bait ball or 2 or more different larger fish swimming close together.

Using an AIRMAR R209LH CHIRP Transducer depths over 10,000' (3000m) have been achieved using 28KHZ (see top & bottom image). Don't need to go so deep? -  then the AIRMAR B265LH CHIRP Transducer will be the perfect choice!