AIRMAR® B175HW 12° CHIRP 1 kW Through-Hull Sonde

The CHIRP High-Wide (HW) technology of this Airmar B175HW transducer uses a wide frequency band, typically between 150 and 240 kHz. Unlike traditional fixed-frequency transducers, CHIRP sends a continuous sweep of frequencies, which provides:

Exceptional target resolution and separation.Clear and detailed sonar images.Better detection of fish and underwater structures, even at high speeds.The "High-Wide" (HW) designation indicates it is optimized for mid-depths and wide cone coverage, ideal for sport fishing.

The Airmar B175HW transducer has an output power of 1 kW (1000 Watts). This high power enables it to penetrate water effectively for accurate and reliable detections, even in challenging conditions.

The 12° tilt of this transducer is designed to compensate for your boat’s hull angle, also called keel angle or deadrise. For optimal performance, the transducer must be installed so that its beam is directed vertically toward the seabed, even when the boat is level on the water. A 12° tilt is typically suitable for hulls with a keel angle between 8° and 15° at the installation point.

Through-hull transducers offer several significant advantages:

Superior performance: They are mounted directly through the hull, minimizing turbulence and interference, providing a clearer and more accurate sonar signal.Reliability: Less prone to damage than transom-mounted transducers, as they are protected by the hull.Versatility: Ideal for a wide range of boat speeds without signal loss due to cavitation.Aesthetics: Once installed, only a small part of the transducer is visible under the hull.

The Airmar B175HW transducer, with its High Frequency CHIRP technology and wide detection cone, is particularly effective for:

Fishing in shallow to mid-depth waters (up to approximately 150–200 meters, depending on conditions).Detecting fish and schools in the upper water column.Identifying underwater structures and bottom changes with high clarity.Fishing with casting or trolling where wide coverage is beneficial.

The Airmar B175HW transducer provides a constant detection cone angle (beamwidth) of 25° across its entire CHIRP High Frequency range. This wide cone covers an extended area beneath the boat, increasing the likelihood of detecting fish and structures.

The Airmar B175HW transducer housing is made of bronze. This material is known for its robustness, durability, and resistance to corrosion in marine environments, ensuring a long product lifespan.

To ensure the longevity and performance of your Airmar B175HW transducer:

Regular cleaning: Clean the transducer face with fresh water and a soft sponge to remove dirt, salt, and marine growth (algae, barnacles) that could accumulate. Anti-fouling: Apply a thin coat of water-based anti-fouling paint (specifically for transducers) if your boat remains in the water for extended periods, avoiding solvent-based paints that could damage the transducer. Inspection: Regularly check the condition of the cable and connector for signs of wear or corrosion.

The Airmar B175HW transducer is specifically designed to be compatible with Garmin fishfinders equipped with an 8-pin connector and supporting CHIRP High Frequency (HW) technology. This typically includes the Garmin GPSMAP, ECHOMAP CHIRP series and certain STRIKER models, provided they have CHIRP capability and the required 8-pin port.

This depends on the model of your Garmin fishfinder. Some recent Garmin models (such as certain GPSMAP or ECHOMAP CHIRP series) already include CHIRP technology and can connect directly to the B175HW transducer via the 8-pin port. Older or less equipped devices may require an external CHIRP fishfinder module (such as the Garmin GSD 25) to work with this transducer.

This transducer is equipped with an 8-pin Garmin connector. It is a standardized connector used by Garmin for its CHIRP-compatible transducers.

The best location to install a through-hull transducer is:

In the flattest part of the hull, where turbulence is minimal.Far from propellers, keels, water intakes, other transducers, and any source of turbulence.Generally toward the bow, where the water is calmest.Ideally, where the deadrise angle matches the transducer’s tilt (12° for this model).Poor installation can lead to signal loss or inaccurate readings.

To ensure perfect watertightness and prevent leaks, follow these critical steps during installation:

Preparation: Thoroughly clean and degrease the installation area on the hull, inside and outside. Sealant application: Apply a generous amount of high-quality marine sealant (polyurethane type) to the transducer body, under the housing lip, and on both sides of the rubber gasket. Tightening: Insert the transducer and firmly tighten the internal mounting nut to compress the sealant and gasket, but without over-tightening. Excess: Remove excess sealant inside and outside before it dries. Drying time: Allow the sealant to cure completely according to the manufacturer's instructions before launching the boat.

To check if a 12° tilt is suitable for your hull, you must measure the deadrise angle of your boat at the exact location where the transducer will be installed. Use an angle gauge or a level app on a smartphone. Place the tool on the inner surface of the hull, perpendicular to the keel line. If the measured angle is close to 12° (between 8° and 15°), then this 12°-tilt transducer is appropriate. The goal is to ensure the transducer face is parallel to the water surface when the boat is stationary.

The Airmar B175HW transducer is a low-profile through-hull transducer designed to be installed directly in the hull without requiring a fairing block in most cases. Its built-in 12° tilt is intended to compensate for the hull’s deadrise angle. A fairing block would typically only be necessary if your boat’s deadrise angle is very pronounced and exceeds the transducer’s compensation capability, or if you are seeking absolutely maximum hydrodynamic performance, which is rare for this type of transducer.