Echonautics BT70L300

300W Low Frequency CHIRP Transducer

This popular series is available in both CW (Continuous Wave) dual frequency or a variety of high-performance CHIRP versions. The low profile thru-hull design minimizes drag below the hull surface and provides superior fish finding and bottom tracking performance at high speeds. This makes it an ideal transducer solution for high-performance centre consoles, flybridge sport fishers, and other popular vessels. With traditional 600W 50/200kHz dual frequency and Low/Medium/High Frequency CHIRP options, the BT70 Series is a versatile performer for many sportfishing vessels. Compatible with major sonar brands, the full BT70 Series is offered in versions with 0o, 12o, and 18o angled elements to accommodate various hull deadrise angles up to 24o while delivering a focused vertical beam on targets below.

This includes three tilt options each for 300W Low Frequency CHIRP (40-75kHz), 300W Medium Frequency CHIRP (95-155kHz), 600W Medium Frequency CHIRP (80-130kHz) and 600W High Frequency CHIRP (130-210kHz).

The CHIRP Advantage

Traditional marine echosounders operate at set frequencies (50 or 200kHz, for example) and transmit a short-duration pulse to display targets under the boat that can be identified by the specific frequency being used. CHIRP sonar (which stands for Compressed High Intensity Radar Pulse) emits a sweep pattern of many frequencies within a long-duration pulse. As a result, the sound energy delivered underwater is up to 1,000 times greater than conventional sonar — providing better deep-water penetration, improved fish detection and target separation, enhanced bottom detail and better sonar performance at higher vessel speeds. CHIRP sonar performance can be further enhanced by selecting a transducer style and CHIRP frequency range that best matches the vessel, water conditions, depths fished, and target species. For this reason, Echonautics offers a range of CHIRP transducers in Low, Medium, and High CHIRP frequency ranges. Our experts can help you find the ideal CHIRP transducer and frequency range to maximize your fishing success.

Tilt / Deadrise:

  • 18° tilt version: for 16° to 24° hull deadrise
  • 12° tilt version: for 8° to 15° hull deadrise
  • 0° tilt version: for 0° to 7° hull deadrise

Mix and Match Adapter Cables

Echonautics transducers come with 8-meter/26-foot cables and standard 8-PIN Male connectors. One-meter/3.3-foot adapter cables are available through Echonautics.

  • CBCCMS0501 Adapter Cable: Male 8-PIN black box connector (Seiwa, SI-TEX, Lorenz, JMC, Polar, MPS and JRC-Europe FF-901)
  • CBCCMS0503 Adapter Cable: Female 8-PIN Garmin connector
  • CBCCMS0502 Adapter Cable: Male 9-PIN Navico connector (Lowrance, Simrad, B&G)

These mix-and-match adapter cables make it simple to integrate high-performance Echonautics transducers with popular sonar systems from leading manufacturers.

Key Features

  • Sonar type: CHIRP ready
  • Frequency: CHIRP 40 - 75 kHz
  • Function: Depth and Temperature
  • Power: 300W
  • Beam width: 47° to 35° @ 3db
  • Mounting: Thru Hull, Hole Diameter 62 mm (2.44”)
  • Material: Bronze
  • Precision Engineering for Reliable Performance
  • Advanced CHIRP Capabilities for Deeper Penetration
  • Clear, Consistent Performance Across the Range
  • Designed in USA, Manufactured in Italy
  • Trusted Support — Backed by a 3-Year Warranty

   Echonautics cross reference
   BT70 ST70 Installation Manual
   Echonautics Brochure_NOV_2025
   BT70 ST70 Dimensions
   CHIRP Wiring Diagram
   300W L CHIRP Technical Data
Spec
Maximum Depth Range Max 366 m (1200 ft)
Weight 1540 g (54 oz)

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BT70L300 300W Low Frequency CHIRP Transducer

  • Brand: Echonautics
  • MPN: See options
  • Model: BT70L300
  • Availability: Pre-Order
  • Lead Time: 5-7 days
  • £666.00

  • Ex VAT:£555.00

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Tags: Echonautics transducer, Seiwa transducer, Lorenz transducer, JRC transducer, Garmin transducer, Simrad transducer, BG transducer, Lowrance transducer, B75L

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