Overview

The Simrad 000-13781-001 is a stainless steel thru-hull transducer that runs High CHIRP (130-210 kHz) with a wide 25° beam and a 12° tilted element. It is a single-channel transducer with depth and water-temperature sensing, and it supports bottom detection down to 310 m (1000 ft) in the right conditions.

This is the kind of install you choose when you want a clean signal and a low-profile housing below the waterline. The 12° tilt helps keep the element closer to level on hulls with some deadrise, which matters when you are trying to hold bottom and keep fish targets crisp while the boat is moving.

Physical size is 134 mm (diameter) x 118 mm, and weight is 2.7 kg. It is suitable for fiberglass and wood hulls, and it terminates with a 9-pin connector on a 10 m (33 ft) cable.

Key features

• High CHIRP operation (130-210 kHz) with a wide 25° beam for more coverage under the boat in shallow to mid depths
• 12° tilted element to help align the sonar beam on thru-hull installations where the mounting spot has noticeable deadrise
• Depth and water-temperature sensing (no speed sensor)
• Stainless steel thru-hull housing for below-waterline mounting on fiberglass and wood hulls
• 9-pin connector with 10 m (33 ft) cable for routing up to the helm or sonar module location
• Housing size 134 mm (diameter) x 118 mm and weight 2.7 kg for planning access, backing clearance, and cable runs

Compatibility and fit

Confirm your sonar source supports High CHIRP and the 130-210 kHz range, and that you have the correct 9-pin sonar port (or the correct adapter if your unit uses a different transducer connector). Because this is a thru-hull style, you will also want to confirm you have interior access for the fastening hardware and enough flat area at the chosen spot for a proper seal.

The wide-beam format is often used when you care about seeing more of what is happening under the boat at once, such as tracking bait and marks while working flats, reefs, or nearshore structure where targets can move through the water column quickly.

Installation notes

Plan this as a below-waterline installation: pick a location with clean water flow, away from intakes, steps, and strakes that can introduce aerated water. The housing needs to be bedded with a marine sealant that is appropriate for below-waterline use, and the cable should be supported and protected anywhere it passes through bilges, rigging tubes, or bulkheads.

Measure deadrise at the exact mounting location, not just the hull spec from the brochure. The 12° tilted element is meant for a moderate-V mounting surface, but the best results come from choosing the correct tilt for the spot where the transducer actually sits.

Maintenance and care

Keep the face of the transducer clear of heavy growth and inspect the sealing area during haul-outs. If you apply any bottom coating in the transducer area, avoid anything that could block or distort the acoustic path.