All guides · Navigation and electronics
I would choose the transducer and plotter as a pair and then check the placement in the boat. A suitable connector is only one part of compatibility; features, frequencies, power, and potentially a sonar module must also match.
What do you need the sonar to help you with?
Write whether you primarily want to know the depth during cruising, find fish, examine bottom structure, or use a specific scanning function. Note typical depths and the speed at which you need a stable image. That is more useful than just looking for the highest wattage rating.
| Mounting method | What to examine |
|---|---|
| Transom mount | Water flow, propellers, hull shape, and protection during trailering or lifting. |
| Thru-hull | Hull material, deadrise angle, location, and safe execution of the thru-hull installation. |
| In-hull | Whether the transducer model can work through the specific material and construction of the hull. |
The placement can determine the result
Garmin's placement guide points to air bubbles, turbulent water, hull parts, and propellers as conditions that can interfere with the signal. The deadrise angle at the mounting location is also significant. An in-hull transducer cannot simply be used through metal or a sandwich-construction hull.
Therefore, have the placement evaluated together with the transducer. For a boat that is to be hauled out, it can be practical to plan the evaluation and mounting in connection with the lift-out. A thru-hull installation requires professional execution and a leak test.
Example: reusing an old transducer
Find the exact model number and take a picture of the connector. Then ask for confirmation of which functions the new plotter can use, and whether an adapter or module is required. An adapter cable can solve a physical connection but does not automatically create new sonar functions.
This is what I would have on the order list
- The plotter's full model name and any sonar module.
- The transducer model and the supported views.
- Hull material, mounting location, and relevant deadrise angle.
- Cable length, cable routing, and manufacturer-approved extensions.
- Brackets, any adapters, and planned work.
Maintain the connector and cable according to the manufacturer's instructions. Do not cut a transducer cable to pass it through a hole without express permission in the manual.
After installation, I would have the functions tested at relevant speeds and depths. Also, choose the depth display reference consciously, so everyone on board knows whether the number refers to the transducer or a set correction.
Sources and manufacturer documentation
Manufacturer documentation checked September 2026. Always follow the manual for the specific model and installation. The calculation examples are simplified examples for planning purposes.
Moving forward with your solution
Send your boat type, hull material, plotter model, and your most important sonar needs, and I will help narrow down the choice.