Installation of navigation electronics on an inflatable vessel with an outboard motor is not just a screwing of the device to a plastic panel, but a complex engineering task that requires taking into account the specifics of the soft board and vibrations.
A properly selected seat and high-quality fastener ensure that during high-speed travel, the sensor will not “nose pecking” or lose contact with water due to cavitation.
In this article, we will take a look at all the steps, from the location selection to the final calibration, so that you get a clear picture of the bottom even on the planing.
Choosing the optimal location for display and sensor
The first step is always to visually evaluate the cockpit, as a universal recipe for all models. Nordman, hunter or Flagship It doesn't exist.
The screen should be in the field of view of the steering, but not to block the view, and be protected from direct glare of the sun and splashes that can distort the image.
The sensor (trander) requires even more careful approach, because its position directly affects the quality of the echo signal.
The ideal installation area is a flat part of the bottom of the balloon or hard floorboard in the aft, but strictly away from the jet of water created by the propeller.
If the sensor falls into the cavitation zone, the device will begin to “blind” at high revs, showing chaotic interference instead of the bottom relief.
⚠️ Warning: Never place the sensor directly in front of the engine's lower unit or in the turbulence zone created by the boat's rental, otherwise the picture will crumble at speed.
When installing on the inflatable floor, it is important to take into account that the soft surface can deform under the weight of the fisherman, changing the angle of operation of the emitter.
In such cases, it is more reasonable to use a remote mount on the transom, which guarantees a stable position relative to the water surface.
Necessary tools and components for installation
Before you start drilling the squirrel board or inflatable elements, you need to prepare the entire arsenal of tools to make the process go smoothly.
To work, you will need a set of screwdrivers, a drill with drills for metal and wood, as well as a high-quality polyurethane-based sealant resistant to salt water and ultraviet.
Pay special attention to electrical wiring, as in conditions of constant humidity and vibration, cheap materials will quickly fail.
Use a copper wire with a cross section of at least 1.5 mm2, be sure to double insulate to avoid voltage loss and short circuit.
- 🔧 Tool kit: drill, drill, cutters, knife for cleaning the insulation.
- ⚡ Consumers: thermal shrinkage, insulation, terminal pads, silicone sealant.
- 🔋 Fastening: stainless steel screws, plastic clamps, installation areas.
- 🛡️ Protection: a fuse of the corresponding nominal value and a moisture-protected socket for connection.
For fixing the wires inside the cockpit of PVC-boats, special adhesive areas with holes under the screeds that are not afraid of moisture are excellent.
Do not forget about the fuse, which is installed in the break of the plus wire as close as possible to the power source - this will save expensive electronics during voltage surges.
Use a heat shrink with a glue layer - when heated, it tightly fits the connection and eliminates moisture from entering the contact, unlike conventional isolating.
Schemes for connecting the sonar to the power source
The most common mistake of beginners is to try to power the sonar directly from the engine’s starting battery or, worse, from the 12V onboard network without protection.
Starting currents of the motor can cause significant interference in the network, which will bring sensitive electronics out of order, so a separate traction battery is ideal.
If you use one battery for the motor and appliances, make sure it has sufficient capacity and is connected through a quality filter divider.
The connection circuit is very simple: red wire (wire)plus) passes through the safety lock to the positive terminal of the battery, black (minus) - to the negative.
Scheme: [Echolote] -- (Red wire + Fuse)-> [AKB (+)]
[Echocholoscope] -- (Black wire) ------------------------ -- -- -- -- -- [AKB (-)]
The length of the wires should be selected with a margin, but without fanaticism: too long cables increase resistance and the risk of tips, and short cables can stretch when moving.
All compounds are best soldered and thoroughly isolated, since twists in vibration conditions on water quickly oxidize and lose contact.
| Type of connection | Advantages | Deficiencies | Recommended section |
|---|---|---|---|
| Separate AKB | Stable voltage, no motor interference | Excess weight, need to charge | 1.5 - 2.5 mm2 |
| General battery (through filter) | Less weight, easier to charge | Risk of interference, discharge with long simple | 2.0 - 3.0 mm2 |
| Through the lighter | Quick connection/disconnection | Low reliability of contact, risk of loss | 1.5 mm2 |
When laying a cable through the side or trawl, be sure to use rubber seals or bushings so that the sharp edge of the hole does not rub the insulation with time.
This is a critical safety feature, neglecting which can lead to short circuits and even fire in the enclosed space of the cockpit.
☑️ Electrical checks
Methods of attaching the sensor to the transom and the bottom of the boat
There are two main ways of fixing the emitter: on a hard transom (for boats with plywood board) and on an inflatable balloon (for a completely soft bottom).
Mounting on a transom is considered more reliable, as it provides a rigid fixation and a constant angle of immersion, independent of the loading of the boat.
For installation on the transom, a special bracket is used, which allows you to adjust the depth of lowering of the sensor and the angle of its inclination.
It is important to install the sensor strictly horizontally relative to the surface of the water when the boat is in a static position.
If your boat is fully inflatable, you will need to use special suction cups or glue pads, but this method is less stable at high speeds.
In this case, the sensor is often mounted on a removable platform that is inserted between the balloon and the floorboard, or use remote brackets clinging to the balloon.
⚠️ Attention: When drilling the transom board, be sure to treat the edges of the hole with an anti-corrosion composition and seal the place of the cable input so that moisture does not get inside the plywood.
The vertical angle of the sensor also plays a role: the front edge must be just below the back for the water flow to flow smoothly around it.
A landing too deep will increase water resistance and can cause the sensor to break off at full speed, and a landing too small can cause signal loss.
How to check the installation angle?
Put the boat down without the motor. The sensor should be fully submerged, but not far below the keel line. If the boat glides and the sounder shows interference, try lowering it 5-10 mm lower or changing the angle of the bracket.
Set-up of parameters and calibration of sonar
After physical installation, the stage of software configuration comes, which is often ignored, relying on factory presets.
However, to obtain maximum detail, you must manually set the sensitivity (Sensitivity) and the depth range.
Start with automatic mode, but then switch to manual to remove unnecessary noise and highlight a useful signal from the fish or relief.
Parameter ASP (Advanced Sound Processing) It helps filter interference, but its excessive value can eat small fish, so be careful.
- 🌊 Sensitivity: Set a 70-80% value to start with, adjusting for the situation.
- 🎚️ Depth range: choose automatic or set with a margin (for example, 20 m at a depth of 10 m).
- 🐟 Fish symbols: For power users, it’s best to turn off and look at the arcs to assess size and activity.
- 🔍 Zoom: Use the enlargement of the bottom layer to study the terrain in detail.
Do not forget about the calibration of the speed of sound, which depends on the temperature and salinity of the water, although for fresh water bodies this is less critical.
Properly configured device will allow you to see not just "porridge", but a clear structure of the bottom, individual algae and silhouettes of fish.
The main secret of a clear picture is not maximum sensitivity, but a correctly chosen balance between sensitivity and frequency of radiation under specific fishing conditions.
Typical errors and troubleshooting in operation
Even with perfect installation, problems can arise due to external factors or improper operation of equipment.
One of the most common problems is the appearance of “dead zones” or the loss of a signal on the go, which is often caused by air entering the working surface of the sensor.
Check if air bubbles are formed due to too sharp angle of attack or contamination of the radiator surface.
It is also worth inspecting the cable for insulation overburdens or damages that may have occurred during active fishing.
If the sonar is turned on but shows nothing, check the integrity of the contacts in the connection connector where water could have hit.
Often, the oxidation of contacts leads to the fact that the device works unstable or spontaneously turns off.
⚠️ Warning: Do not leave the sounder on without immersing the sensor in water for more than a few minutes – this can cause the emitter to overheat and fail.
Clean the sensor regularly from plaque of algae and silt using soft fabric and water, avoiding abrasive cleaning products.
Timely maintenance will prolong the life of your equipment and ensure stable operation at the most critical time of fishing.
What if the sounder shows a double bottom?
This often happens on a solid clay bottom or at a high sensitivity. Try to reduce sensitivity or switch the frequency of radiation (if the model allows) to remove the echo signal.
Can I install a sonar on a boat without drilling a transom?
Yes, there are suction-sensing models or special brackets that are attached to the side or balloon with belts and clamps, but at high speeds, this mount is less reliable and can give vibration.
Which battery is better to choose for a sonar?
The optimal solution is a separate gel (GEL) or AGM battery with a capacity of 20 Ah. It is resistant to deep discharges and vibrations, which is critical for inflatable boats.
Why does the sonar lose its signal at speed?
The sensor is likely to come out of the water or get air under it (cavitation), you need to lower the sensor below or change the angle of its inclination relative to the transomb.
Do I need to take off the sensor for the winter?
It is advisable to dismantle the electronics and sensor for storage in a warm dry room, plastic and electronics can crack from the cold, and the cable becomes brittle.