Overview

The Garmin GT17M-THF is a 1 kW stainless steel thru-hull transducer that runs medium band CHIRP (80 to 165 kHz) through an 8-pin connection for traditional sonar depth and target returns.

It covers a 9° to 18° beamwidth and is rated for depth performance up to 2,400 ft in freshwater and 1,800 ft in saltwater. Depth and water temperature sensing are built in, and the attached cable is 50 ft for routing back to a compatible Garmin display or sonar module.

Because the element is built with a fixed internal tilt, the beam can be kept closer to level with the waterline on hulls with different deadrise angles, which helps readings stay consistent when the boat is moving.

Key features

• 1 kW medium band CHIRP frequency range: 80 to 165 kHz
• Beamwidth: 9° to 18°
• Rated maximum depth: up to 2,400 ft in freshwater and 1,800 ft in saltwater
• Flush thru-hull stainless steel housing with tilt options to match hull deadrise
• 8-pin connector with 50 ft cable for typical Garmin sonar wiring runs
• Built-in depth and water temperature sensing
• Auto-ID support for plug-and-play recognition on supported Garmin sonar systems

Variants

This transducer is offered with different internal tilt angles so the sonar beam can be aligned to the waterline on a range of hull deadrise angles.

All versions share the same 1 kW medium band CHIRP (80 to 165 kHz), stainless steel thru-hull body, 8-pin connection, 50 ft cable, and depth and temperature sensing. The tilt angle is the selection point.

• 010-02930-00: Tilt 0°. Fits hull deadrise angles from 0° to 7° at the mounting location, common on flatter bottoms and some planing hulls.
• 010-02930-01: Tilt 12°. Fits hull deadrise angles from 8° to 15°, a typical range for many deep-V bay boats and offshore center consoles.
• 010-02930-02: Tilt 20°. Fits hull deadrise angles from 16° to 24° for steeper V hull sections where a straight element would point off-axis.

Installation and setup

This is a thru-hull installation below the waterline, so placement matters. Mount it in clean water away from strakes, intakes, discharges, and anything that feeds air or turbulence to the face of the transducer.

Cutout size is 98 mm (3 7/8 in.) in fiberglass and 101 mm (4 in.) in metal hulls. Use a flexible, fast-cure marine sealant rated for below-waterline fittings, then check for leaks after launch before leaving the boat in the water for an extended period.

For 12° and 20° tilt models, the top cap arrow needs to point toward the keel so the internal angle offsets the hull deadrise correctly. Route the cable away from engine components and high-current wiring to reduce sonar noise, and plan for a chartplotter software update as part of the install.

Hull materials and corrosion considerations

The stainless steel housing can be installed in fiberglass, wood, composite, aluminum, or steel hulls. When mounting in aluminum or steel, galvanic isolation components are used between the housing and the hull to help prevent corrosion around the fitting.

What’s included

• GT17M-THF thru-hull transducer
• Jam nut
• Spacer
• Washers
• Set screws
• Galvanic isolation components
• Documentation

Maintenance and care

Keep growth off the transducer face for consistent readings. Water-based anti-fouling paint can be used around the installation area, but avoid ketone-based paints and harsh solvents when cleaning. A soft brush and mild detergent are usually all it needs.

On-the-water use

This transducer is a good match for boats that want solid medium-band CHIRP performance for finding structure, tracking bottom at speed, and working bait and marks in coastal and offshore depths. The tilt options matter most when you are trying to hold clean bottom and consistent targets on a V hull.