The high-quality installation of a sonar on a boat is not just drilling holes on board, but a complex task, on which the effectiveness of your fishing depends. sounder It provides a clear picture of the bottom, allows you to see fish and avoid underwater obstacles, whereas errors in installation lead to loss of signal and a "noisy" screen. Many anglers underestimate the importance of choosing the location and method of attachment, relying on the case, but it is the details that determine the result.
In this article, we will analyze all the nuances of the installation, from the choice of transom mounting to laying a cable across the entire side of the boat. Hydrolocator It's a sensitive device that requires stable contact with water and no air bubbles under the emitter, and you'll learn how to avoid common mistakes that beginners make, and you'll get a step-by-step algorithm for mounting on boats made of different materials.
Before you take up the drill, you need to clearly understand the type of your boat and operating conditions. aluminum-boat It's very different from PVC or fiberglass, and ignoring the physical properties of the hull materials can lead not only to poor performance, but also to a leaky vessel, and let's figure out how to do it right the first time.
Choosing the optimal location for mounting the sensor
The first and most critical step is to find a clean spot on the transom, where the water flow is laminar, without vortices or air bubbles. If the sensor gets into the turbulence zone created by the screw or by the elements of the contours of the body, the screen will appear chaotic stripes that hide the fish. The ideal zone is below the waterline, but above the line where air bubbles form when moving.
When choosing a location, you also need to consider the angle of the sensor. emitter If the boat has a pronounced keel or steps on the transom, this complicates the task, requiring the use of additional alignment plates or shifting the sensor to the side, the wrong angle will lead to the loss of the bottom at high speeds.
Conduct a test run by temporarily fixing the sensor on a suction cup or tape at different points of the transom to find the zone with the cleanest signal before drilling holes.
It is important to be aware of the proximity to other electronic devices. GPS antennasRadios and especially motors create electromagnetic tips that can drown out a weak echo, distance to other sources of radiation should be maximum, and cables should not lie parallel to each other in long areas without crossing at right angles.
Comparison of fastening methods: transax, cut-through and through
There are three main ways of installation, each with its own advantages and disadvantages depending on the type of boat and the aesthetic you want. transom mounting It's the most popular and easy to implement, and it doesn't require any disruption to the integrity of the shell, but it's vulnerable to mechanical damage when moored and creates additional water resistance.
Through-cutting (in-hull) involves inserting the sensor directly into the hull below the waterline, which is ideal for high-speed boats, because the sensor does not create resistance or break down by the flow, but it requires drilling the hull, which is strongly discouraged in aluminum boats because of the risk of electrochemical corrosion, and is not possible on inflatable vessels.
Through-cut nuances
When installing the sensor through the side, it is important to use a special sealant compatible with the body material (polyurethane for fiberglass, thiokol for metal), and be sure to make openings to avoid microcracks during vibration.
The third option is to attach to the inner wall of the body (relevant to fiberglass and some plastics), and the sensor is glued to the inside of the side, and the signal passes through the material. It is aesthetically and safely, but only works with single-layer housings without reinforcing elements and foam fillers at the installation site. Aluminum boats this method is not suitable due to the shielding of the signal with metal.
Below is a table that helps to determine the choice of installation method:
| Mounting method | Type of boat | Complexity | Risks. |
|---|---|---|---|
| Trants. | Any (PVC, metal, plastic) | Low. | Failure on impact, resistance |
| Through (In-hull) | Glass plastic, wood | High. | Leakage, corrosion (on metal) |
| Internal (Through-hull) | Glass-plastic (single-layer) | Medium | Loss of signal through foam |
| On a suction cup (Temporary) | Anyone. | Minimum | Instability, disruption at speed |
Instructions for installation on PVC boats
Inflatable boat owners face a unique challenge: the lack of a rigid transom or its insufficient rigidity for standard mounts. For such cases, special plastic holders have been developed that are fixed to an inflated cylinder or a rigid transmoltar board, the main requirement is to ensure that the design is rigid so that the sensor does not “walk” in the water, creating interference.
The installation process begins with the selection of a point on a transom board or a special bracket, you need to drill a hole and fasten the holder with wide washer bolts so as not to damage the plywood or plastic. Sonar cable You should immediately fix screeds, excluding it from getting under the screw or into the water.
☑️ Verification of PVC installation
If you use a balloon attachment method, you use suction cups or Velcro straps, but they're only suitable for low speeds. At high speeds, the flow of water will be disrupted by a light sensor. In such cases, it's better to use remote sensors attached to a separate rod that is lowered overboard into the water, which guarantees a stable signal regardless of the position of the boat.
⚠️ WARNING: When mounting on a transom board, make sure the bolts don't go right through and have sharp ends inside the boat that could injure the fisherman or damage gear.
Installation on metal and fiberglass housings
Installation on metal and fiberglass requires a more serious approach to sealing and anti-corrosion protection. aluminum-boat It is strictly forbidden to use copper cables or sensors with copper elements in direct contact with water and the housing, as this will cause rapid galvanic corrosion.
When drilling fiberglass, it is important to prevent material from stratifying, drilling at low revs using special composite drills, the cable hole must be thoroughly cleaned, degreased and filled with epoxy sealant before pulling the wire, which will create reliable waterproofing and prevent moisture from entering the board.
Protection against electrochemistry
On metal boats between the hull and the sensor bracket (if metal), it is recommended to lay a dielectric gasket or use plastic washers to break the electrical circuit.
Once the transom sensor is installed on a rigid body, you need to check the angle of inclination in statics and dynamics, and often you need to put washers under the mount to align the working surface of the emitter with respect to the horizon. Horizontal position It is critical for DownVision or SideVision technologies, where angle distortion leads to an incorrect display of the picture on the sides.
Cable laying and interference protection
The cable track is the arteries of your echolocation system, and the wire should be laid as far as possible away from the battery power cables and engine ignition wires, the power lines can only be crossed at right angles, and to protect against mechanical damage, it is recommended to stretch the cable inside a corrugated tube or a special cable channel, especially in the passageways over the side.
At the places of cable insertion into the housing or through the transom tile, sealants are necessarily used. The rubber seal should tightly cover the wire around the perimeter. Before tightening the coil, the wire and the rubber cuff can be lubricated with silicone lubrication for better slip and tightness.
If the cable is too long, it should not be twisted or shortened arbitrarily, as this will violate the wave resistance and cause signal loss. The excess wire should be carefully rolled into a bay with a diameter of at least 10-15 cm and fixed in a dry place, for example, under the dashboard or in a jounduk.
⚠️ Warning: Never cut off the power connectors or sensor while trying to build up the cable – this instantly voids the warranty and can cause the device to fail due to a mismatch of parameters.
Customization and calibration after installation
After physical installation, there is a software adjustment phase, where you first need to choose the right sensor type in the menu if it is not automatically determined, then calibrate the depth if the sensor is not vertically mounted, but at an angle (although this is rare for transom models), the main setting is to adjust the sensitivity (Sensitivity) and noise reduction (Noise Rejection).
On calm water, set the sensitivity to maximum until the screen does not appear "noise", then gradually reduce it until the background is clear. Radiation frequency It's chosen depending on the task: 83 kHz gives a wide cone and a view, and 200 kHz gives a detailed picture at the depth. For fishing in shallow water, high frequencies are preferred.
Proper sensitivity setting is more important than the power of the device – too high noise reduction can “eat” small fish, and too low will flood the screen with interference.
Be sure to check the sounder at different speeds. If the bottom disappears at high revs, it may be due to cavitation or insufficient entraction, in which case it may be necessary to lower it lower or change the angle of inclination of the transom (if the design of the boat allows).
Frequently Asked Questions (FAQ)
Can I install a sonar on an inflatable boat without drilling?
Yes, there are special PVC attachments on suction cups, Velcro straps or brackets that are worn on a balloon, and floating sensors that are simply thrown overboard into the water and connected wirelessly or by cable are also popular.
Why does the sounder show “arcs” instead of fish?
The arcs are the perfect signal from a fish passing through the cone of the emitter. If you see solid lines, maybe the boat is standing still or moving very slowly. The arches require the boat to move relative to the fish.
How to protect the sensor in winter?
If this is not possible (through mounting), make sure that there is no ice around it, which, when expanded, can split the plastic case of the emitter.
Does the thickness of the boat's bottom affect the signal?
Yes, when you're inside, the signal passes through the body material, the plastic and the plastic transmit the signal well, the aluminum and steel shield the signal completely, so for metal boats, only external (transe) installation is possible.