Raymarine TM185HW CHIRP Transom Mount Transducer, Depth/Temperature, 1kW, 150-250 kHz, 25 deg Beam

Overview

The Raymarine A80804 is a TM185HW high-wide CHIRP transom-mount transducer for depth and fast-response water-temperature sensing on fishing and cruising boats. It runs at 1 kW and covers the high-frequency CHIRP band from 150 to 250 kHz, with a fixed 25 degree beamwidth that gives broad coverage under the boat while keeping the detail boaters expect from high-frequency sonar.

This transducer is made for transom installation on outboard and inboard/outboard powered boats, with a stainless steel bracket and a SEALCAST seamless urethane housing for long service in the water. It is recommended for both planing and displacement hulls, with support for transom angles from 3 degrees to 21 degrees.

The high-wide band includes the commonly used 200 kHz frequency and gives 100 kHz of total bandwidth from one transducer. Maximum depth is rated to 152 m or 500 feet, making it a strong match for inshore fishing, coastal runs, and offshore fishing where wide coverage and target separation matter more than extreme-depth performance.

Key features

• 1 kW CHIRP transducer with depth and fast-response water-temperature sensing.
• High-frequency CHIRP range from 150 to 250 kHz for detailed bottom returns and fish-target separation.
• Fixed 25 degree beamwidth keeps coverage wide across the high-frequency band.
• Rated to a maximum depth of 152 m or 500 feet.
• Includes the popular 200 kHz frequency within its 100 kHz high-wide bandwidth.
• Transom-mount format suits outboard and inboard/outboard powered boats.
• Stainless steel bracket supports installation on planing and displacement hulls.
• SEALCAST seamless urethane housing is built for continuous use in the water.
• Patented Xducer ID technology helps compatible Raymarine sonar systems identify the connected transducer.
• Recommended for vessels up to 10 m or 33 feet.

Installation and fit

The TM185HW mounts on the transom, which keeps the installation outside the hull and avoids cutting a large thru-hull opening. The stainless steel bracket is intended for the stern of boats with outboard or sterndrive power, where the transducer can be positioned in clean water flow for better readings while underway.

For the best sonar performance, the mounting location should stay below the waterline at operating speeds and remain clear of turbulence from strakes, steps, thru-hulls, trim tabs, and propeller wash. The specified 3 degree to 21 degree transom angle range helps confirm whether the stern geometry is suitable before installation.

Sonar performance on board

The fixed 25 degree high-wide beam gives more coverage in the upper water column than a narrow high-frequency beam, which helps when marking bait, fish, and structure around the boat. It is especially useful for anglers working coastal grounds, reefs, wrecks, and pelagic zones where fish may not pass directly under the keel.

Because this is a high-frequency CHIRP transducer, it is aimed at detail, target separation, and coverage down to its rated depth rather than very deep offshore sounding. It suits boats where the owner wants a clean transom installation and a sonar view that makes fish arches, bottom changes, and water-temperature readings easier to interpret.

Materials and marine environment

The urethane housing and stainless steel bracket are appropriate for wet transom exposure, including saltwater use when installed and maintained correctly. As with any transom transducer, periodic inspection matters: keep the face clean, check the bracket hardware, and make sure the cable is secured away from chafe, sharp bends, and moving gear.