Raymarine CPT-S Transom Mount Transducer, High CHIRP, 25° Conical Beam, 900 ft

Overview

The Raymarine E70342 is a CPT-S conical High CHIRP transom mount transducer for Raymarine fishfinder and chartplotter systems that use CPT-S sonar. It supports single High CHIRP sonar through a 25° conical beam, records depth, and can read to a depth range of up to 900 ft, or 274 m, when conditions allow.

This transducer is built for boats that need a transom-mounted depth and fish-targeting sensor without DownVision imaging. The urethane housing suits fiberglass, wood, and metal hulls, and the transom format works well on many outboard-powered boats where the sensor can sit in clean water flow at the stern.

The unit includes an integrated seawater temperature sensor and a 10 m cable, giving installers enough length for many helm runs without placing the display too close to the stern. Compatibility depends on the display or sonar module being used, and some Raymarine systems require an adapter cable.

Key features

• Single High CHIRP sonar with a 25° conical beam for depth reading and fish targeting.
• Depth range rated up to 900 ft, or 274 m, for coastal fishing, cruising, and general bottom tracking.
• Integrated seawater temperature sensor for displays that support temperature data from the transducer.
• Transom mount format for stern installation on suitable hulls, especially many outboard-powered boats.
• Urethane housing for use on fiberglass, wood, and metal hulls.
• 10 m cable helps with routing from the stern to the helm or electronics area.
• High CHIRP only, with no DownVision capability, so it should be matched to the sonar view the vessel actually needs.

Compatibility and fit

The CPT-S transducer family connects directly to Raymarine Element S chartplotters. It can also be used with Axiom DV models directly, while other sonar-equipped Axiom displays, Axiom Pro S, and Axiom 2 Pro S installations may require the A80490 adapter cable. Element HV installations use the A80559 CPT-S/DownVision 9-pin adapter cable, and the connected display will still receive High CHIRP sonar only.

Because this is a transom-mount transducer, placement matters. The sensor should be installed where it stays in clean, aeration-free water while the boat is underway, away from strakes, steps, turbulence, and prop wash whenever possible.

Installation and setup

The transom bracket installation keeps the sensor outside the hull, which avoids drilling a large through-hull opening and makes it a practical fit for many trailer boats, center consoles, small cruisers, and fishing boats. Cable routing should avoid sharp bends, high-heat areas, and runs beside heavy current wiring where electrical noise may affect sonar performance.

After mounting, the transducer angle and height should be checked on the water. A clean bottom return at speed usually depends on both the mounting location and the way the transducer face meets the water flow.

What’s included

• CPT-S transom mount transducer
• Mounting bracket
• 10 m cable