For any fisherman using a polyvinyl chloride swimmer, a high-quality sonar is not just a toy, but the main navigation tool for finding fish and bottom relief. However, in order for the instrument to show true information, rather than chaotic glare and noise, you need to ensure the correct radiator Errors in the installation phase often cause expensive equipment to stop “seeing” the bottom at speeds above 10 km/h or to give false signals.
The problem of installation on a soft side is radically different from installation on a hard transom boat, as it requires taking into account the elasticity of materials and the lack of rigid support. In this article, we will discuss in detail all the nuances of location selection, fixation methods and adjustment that will ensure the stable operation of your sonar in all operating conditions.
Choice of softboard anchorage type
The first and most important step is to determine the method of fixation that will be compatible with the design of your boat. The market offers several solutions, each of which has its own advantages and disadvantages, depending on the type of transom and the planned speed of movement.
The most popular solution is transom-holdingIt provides a rigid fixation and allows easy adjustment of the angle of inclination, which is critical for adjusting the angle of radiation. However, on PVC boats with an inflatable transom or soft bottom, this option can cause vibrations that are transmitted to the entire hull.
The alternative is sucker Suction brackets are convenient for their mobility and no need to drill or glue elements, but they are less reliable at high speeds and in overgrown water bodies. Hard bottom brackets are considered the “gold standard” for serious anglers, since they completely eliminate contact with the sides and provide perfect hydrodynamics.
- 📌 transom brackets - classic for boats with a hard or reinforced transcension, require minimal improvements.
- 📌 Suction mounts are ideal for temporary installation or testing of equipment without interference with the design.
- 📌 Hard bottom platforms – provide maximum signal stability and no interference from the engine.
- 📌 Cutting sensors – require professional installation directly into the cylinder, which irreversibly changes the design of the boat.
⚠️ Attention: The use of universal plastic staples from sonars designed for aluminum boats on thin PVC without gasket can lead to wiping the cylinder material during prolonged parking in the sun.
Preparation of the installation site and sensor protection
Before the final installation is completed, the surface and the sensor must be carefully prepared, and not only does the reliability of the mounting depend on the quality of the preparation, but the durability of the emitter itself, which is the most vulnerable element of the system, and ignoring this step often leads to rapid failure of the equipment.
Particular attention should be paid cable-protection On PVC boats, the cable is often squeezed between the sides when packing or rubbed against the rough surfaces of the transom, and special Cambrians or corrugated hoses are recommended to protect the wire at points of contact with the boat structure.
If you choose to stick the platform or fix the transom, the surface should be defatted and sand-cleaned. For PVC materials, alcohol solutions or specialized cleaners that do not contain acetone, which can damage the structure of the polymer, the purity of the surface ensures that the glue or suction cup will hold as efficiently as possible.
The important point is orientation. work-surface It has to be exactly parallel to the surface of the water in the static position of the boat, and any distortion will cause the sensor to "catch" air bubbles or the surface of the water, losing contact with the bottom.
Use a piece of old car camera or tight rubber as a gasket between the plastic bracket and the soft transom, which will reduce vibration and prevent PVC material from squeezing.
Installation on the transom: step-by-step instructions
Installing the sensor on a transom is the most common method, requiring accuracy and consistency. If you do the right installation, you can forget about the sonar problems for the whole season. Let's take a closer look at the process to eliminate the typical novice errors.
The sensor must be immersed in water to a depth sufficient for a stable signal, but not create excessive resistance. It is usually recommended to retreat from the bottom edge of the transom 30-50 cm, but this figure can vary depending on the design of the boat and the type of engine.
☑️ Checklist of mounting on the transom
To fix the bracket itself, stainless bolts or specialized glue for PVC are often used, if the design allows. When using bolts, be sure to apply wide washers on the inside of the transom to distribute pressure and not damage the cylinder. The thread joints should be treated with a thread locker, since the vibration of the motor can weaken even a tight screw in a couple of hours.
Once the brace is physically installed, a sensor is inserted into it and a nut is fixed, so it's important not to pull the plastic case over so as not to break the thread, but also to leave the backlash. The cable is carefully placed along the side or transom and fixed with screeds or glue patches, eliminating sagging and the risk of hitting the screw.
| Parameter | Recommended value | Criticism |
|---|---|---|
| Depth of immersion | 10-15 cm below bottom | High. |
| Inclination angle | Perpendicular to water | Critically. |
| Distance from motor | Minimum 30 cm | Medium |
| Diameter of the washer | At least 20 mm | High. |
Hard bottom installation (NDS)
Owners of low-pressure inflatable floor (LDPB) or floorboard bottom boats often choose to install the sensor directly on the bottom, a method considered one of the most effective because the sensor is located in the calm water zone, far from the air bubbles created by the motor and gearbox.
To implement this method, a special platform-heel is used, which is glued to the PVC material. The key factor of success here is the choice of the right one. glueConventional superglue or silicone will not work here - you need polyurethane glue or a specialized two-component composition for PVC, which provides chemical welding of materials.
The installation process begins with careful placement marking, the sensor should be placed in the center or closer to the stern, but strictly on the keel line to minimize the impact of the rolls, the surface is degreased, a primer is applied (if required by the instructions to the glue), and then the site is glued.
Once the adhesive has been dryed (usually it takes 24 hours to fully polymerize), the sensor itself is installed on the site, with the ability to remove the sensors, which allows sensitive electronics to be captured when transporting the boat in a deflated form, leaving only an inexpensive plastic base in place.
⚠️ Warning: Never put a sensor or platform on a deflated boat. Installation and drying of the glue should only occur on a fully inflated product, otherwise the glue will move away with the piece of material when inflated.
How to remove old glue without damage to PVC?
If you need to remove the glued platform, use a dryer to heat the glue to 60-70 degrees. The heated composition becomes elastic and is removed with a plastic spatula. The glue residue is removed with a special PVC solvent or white spirit, but you need to act carefully without rubbing the chemical over a large area.
Echo sounder setting and calibration
Physical installation is only half the battle, and to make the picture on the screen clear and the fish arcs pronounced, you need to properly configure the software part of the device, and many users underestimate this step, relying on factory settings, which are rarely ideal for specific conditions.
First of all, you should calibrate. speed In water, if your sonar is manually tuned, the density of water varies with temperature and salinity, which directly affects the accuracy of the depth mapping. In fresh water at 20°C, the speed is about 1,482 m/s, but in cold water it is lower.
The sensitivity must be adjusted (Sensitivityand depth range (RangeAutomation often makes noise or loses bottom in overgrown areas, and experienced users prefer to manually set the upper limit of the range slightly above the current depth to increase the detail of the bottom layer.
An important parameter is radiationFor standing water and detailed examination of the bottom, high frequencies (200 kHz) are better suited to give a clear picture. For greater depths and searching for fish on the go, low frequencies (50 kHz) are more effective, which penetrate the water column but give a less detailed image.
- 🎚️ Sensitivity – regulates the level of signal amplification, allowing you to see small fish or weed out debris.
- 🌊 Scrolling speed – affects the screen refresh rate, is important when moving a boat.
- 🎨 Color palette – Selecting a display scheme (e.g., “White Line”) helps to better distinguish the structure of the bottom.
- 📡 Noise suppression is a filter that removes radio interference and tips from the motor.
Typical problems and ways to solve them
Even with proper installation, there can be situations where the sonar is not behaving properly, and understanding the nature of these problems will quickly fix the malfunction right on the pond without interrupting fishing, most of which are solved by simply adjusting the position of the sensor.
One of the most frequent problems is speed-lossThis phenomenon, known as cavitation, occurs when air bubbles form around the sensor that shield the ultrasound signal, most often because the sensor is too high or the angle of inclination is wrong.
Another common problem is the appearance of "curtains" or vertical stripes on the screen, which indicates the presence of interference that can come from the running engine, sonars of other nearby boats, or even from the operation of the storm pump pump pump, in which case changing the frequency or turning on the noise cancellation filter helps.
If the sonar shows double bottoms or floating arcs where there are no fish, check the mounting. The sensor's luft, even microscopic, causes the angle of radiation to fluctuate and distort the picture, and it's also worth checking the condition of the cable for insulation bending or damage.
90% of the problems with the sonar on PVC boats are associated with the wrong angle of installation of the sensor or the entry of air bubbles into the work area of the emitter.
Why does the sonar show depth but not fish?
There may be several reasons: too low sensitivity, set in automatic mode; the wrong frequency for this type of bottom (at the rocky bottom, the signal is scattered); or the fish is in the "dead zone" directly under the sensor, where the beam has not yet formed. Try to increase the sensitivity manually and change the frequency.
Can I leave the sensor on the boat when stored?
If the boat is kept deflated, the transom-mounted sensor is better removed to avoid cable clogs and damage to plastic elements when rolling up. The glued platforms can be left behind, but the emitter itself is desirable to be dismantled. Prolonged exposure to ultraviolet light on the sensor plastic is also undesirable.
How does the thickness of the balloon affect the sounder?
The thickness of the PVC material is not in itself a barrier to ultrasound if the sensor is installed outside (in water). However, if you plan an in-hull installation, which is extremely rare with PVC due to the complexity of sealing, the multilayer reinforcement and air layers can greatly distort the signal. For PVC boats, only external installation is relevant.
What to do if the sounder cable is worn?
Recovery of the sonar cable is a delicate task, a simple twist will break the wave resistance and cause interference, you need to use a solder with high-quality insulation of each vein separately, and then general sealing with thermal shrinkage, if the connector itself is damaged, you better replace the cable entirely or contact the service, because the leakage of the connector will lead to water entering the sonar block.