Modern fishing has changed dramatically with the advent of affordable electronic assistants, and now fishermanship The demand-driven instructions have become the standard for those who want stable catches. Many aspiring anglers mistakenly believe that it is enough to simply fix the device on a transom and press the switch on, but real efficiency is achieved only with a deep understanding of the principles of the sonar. Your device displays not just a picture of the bottom, but a complex acoustic map that requires the right interpretation to find promising points.
In this article, we will explore the intricacies of using sonar in the field, drawing on practical experience and visual examples, learn how to distinguish a thermocline from a school of fish, why it is important to adjust sensitivity correctly, and how to avoid common mistakes when wiring a boat above a point. Garmin, Lowrance or Humminbird Regardless of the brand, the physical principles of sound wave propagation remain unchanged.
To consolidate theoretical knowledge is extremely useful to look at videoWe structured the information so that you can immediately apply the knowledge to the body of water, increasing your chances of catching a trophy, and let's dive into the world of underwater echolocation and turn the chaotic dots on the screen into a comprehensible navigation map.
The principles of sounder and reading echogram
The key to understanding this process is knowing how ultrasonic pulses interact with underwater objects. It emits a cone-shaped signal that bounces off the bottom, fish and vegetation, and goes back to the sensor. The signal return time is converted into distance, forming a vertical slice of water underneath the boat on the screen. Signal frequency High frequencies (200 kHz and above) give a detailed picture in shallow water, and low frequencies (50-83 kHz) penetrate greater depths, but with less resolution.
When studying an echogram, it's important to look not only at the presence of arcs, but also at the structure of the bottom. A solid rocky bottom gives a narrow, clear line, while a silky bottom blurs the signal, making the line wide and less contrasting. The fish is displayed as characteristic arcs, the shape and size of which depend on the speed of the boat's wiring and the size of the object. If the boat is anchored, the fish will appear as a vertical stripe as it passes through the scanning cone.
⚠️ Warning: Do not confuse air bubbles rising from a running motor or anchor chain with fish, which create characteristic vertical columns of interference that can completely block the useful signal on the screen.
Modern models are equipped with technologies such as DownVision or StructureScanIt's a way to distinguish between individual driftwood branches, types of bottom soil, and even fish behavior in real time. Understanding the difference between a traditional 2D sonar and a side scan is critical to the choice of fishing tactics in different environments.
Selection of equipment and installation on the boat
Choosing the right device is half the success. For fishing from a PVC boat or a small aluminum boat, compact models with a screen diagonal of 5-7 inches will be the best solution. Larger screens can be uncomfortable in a cramped cockpit, and too small screens will not allow you to see the details of the echogram in bright sun. The key parameters for choosing are the power of the emitter and the presence of a GPS module to save the way points.
The sensor needs a special approach, because it depends on the quality of the image. The sensor must be installed strictly horizontally relative to the surface of the water when the boat is moving. If the boat's nose is jacked up when planing, the sensor also changes the angle, which leads to loss of contact with the bottom and the appearance of noise on the screen. Use the rotary brackets to accurately adjust the angle of inclination.
- 🛶 Tranza installation: The most common option, the sensor is attached to the back wall of the boat, it is important to ensure a dive 15-20 cm below the bottom.
- 🔌 Cable management: The wires must be securely secured and have no loops that can wind on the engine screw or cause interference.
- 🔋 Power supply: Connect the sonar directly to the battery through the fuse, avoiding twists and the use of standard connectors on the onboard network, if they are not sealed.
Don't forget to protect against interference. The sonar wiring should not lie next to the wires from navigation lights or radios, as this can cause tips on the screen. The shielded cables and high-quality connection insulation will help avoid problems with the "snow" on the display.
Set up the sounder before going to water
Factory settings rarely match specific fishing conditions, so manual calibration is required. The first thing you need to do is select the language, units of measurement (meters or feet) and the operating mode of the sonar.Auto) often “hiding” small fish or relief details, seeking to show just the bottom, so experienced anglers prefer manual sensitivity adjustment (see below).Sensitivity) and depth range (Range).
Sensitivity is the most important parameter. If it's too high, the screen will be filled with noise and chaotic dots, if you don't see the fish, the optimal value is when there's light noise on the screen, but the picture remains readable. Zoom (approximation), which allows you to consider in detail the bottom layer, where the fish often stands.
Recommended starting settings for depths of 2-10 meters:- Frequency: 200 kHz (High)
Sensitivity: 75-85%
- Scrolling speed: 50-60%
Color palette: Day Color (for a sunny day)
It is important to adjust the color palette depending on the time of day. For day fishing, contrast schemes with blue or white backgrounds are suitable, and for dusk or night it is better to switch to dark colors (for day fishing, it is better to switch to dark colors).Night Mode) to avoid blinding eyes and to see weak signals, some models allow you to create custom profiles of settings for different types of bodies of water.
Tactics of finding fish from a boat
Searching for fish with sonar is not a chaotic ride through a reservoir, but a systematic survey of promising areas. First, you need to study the bottom relief, finding eyebrows, dumps, pits and hills. Fish often stand at the depths where they are more comfortable to hunt. Move zigzag or parallel gals to cover the maximum area and fix the coordinates of interesting places in the GPS navigation.
When a fish appears on the screen, you don't want to drop anchor or throw gear right away. You need to determine the nature of the bottom below it: if it's pure sand or silt, the fish can be passive. If you see a structure under the fish (rocks, snags), the probability of successful fishing increases. It's also important to monitor the water temperature, because many species of fish are tied to certain types of fish. temperature-layer (thermoclins)
| Type of object on screen | Visual description | Probability of fish | Recommended action |
|---|---|---|---|
| Douga (Arca) | Clear semicircular line | High (90%) | Stop and catch |
| Vertical stripe | Line under the boat in the parking lot | Medium (fish in a cone) | Check for echoes |
| A blurred cloud | Unstructured points | Low (plankton/garbage) | Ignore |
| Double arc. | Two arches above each other | Very tall (large fish) | Start fishing now. |
If you find a school of fish, it's helpful to do a few wirings from different sides to understand the direction of the pack, which will help you choose the right position to throw the gear. Remember that the sonar shows what's directly under the boat, and the throw is usually done 10-20 meters to the side, so consider the demolition of the boat with wind and current.
Analysis of bottom relief and structures
Understanding the bottom is key to finding predators. The sonar allows you to see not just the depth, but also the structure of the bottom coating. The solid bottom reflects the signal more strongly, creating a wide colored stripe at the bottom of the screen, while soft silt absorbs some of the energy, making the line thin. The presence of hard areas against the background of soft silt often indicates a shell or pebbles, where perch and perch like to feed.
When you look at the water, look at the anomalies, the extremes of the depths, the single bumps, the ditches, these are natural shelters for fish. White Line (white line) helps to separate the signal of the bottom from the signal of the fish, which is in close proximity to the ground, which is critical when catching bottom tackle.
And visualizing vegetation also provides important information: dense grasses are shown as broad, blurry stripes rising from the bottom. Fish often stand on the boundary of clear water and grass or in windows among vegetation. But it's worth remembering that thick grass can shield the signal by hiding the fish underneath.
⚠️ Warning: When you move from depth to shallow water (and vice versa), be sure to manually adjust the depth range (Range), otherwise the sonar may not have time to reconfigure and you will lose the image of the bottom or fish.
Common mistakes and their elimination
One of the most common mistakes is that the boat is moving too fast when scanning, and if the boat is moving faster than the screen is being updated, the picture is stretched and unreadable, and the optimal speed for a detailed examination of the bottom is 3-5 km/h. For a quick search, you can increase the speed, but the detail will suffer.
Another mistake is to ignore the interference from the motor. The running engine, especially at low speeds or when trolling, can create cavitation bubbles that jam the sensor signal, in which case it helps to install the sensor deeper or use the remote sensor on a separate bracket away from the flow of water from the screw.
- 📉 Bottom loss: Check the angle of the sensor and reduce the speed of the boat.
- 🌫️ Lots of noise: Reduce sensitivity and check the cable attachment.
- 🐟 No arcs: Increase the speed of scrolling the screen or change the course of the boat across the brow.
Users also often forget to update their devices' software, manufacturers regularly release firmware that improves signal processing algorithms and fixes bugs, and checking the software version's relevance is a simple procedure that can significantly improve your work. sonar.
Why does the sonar show the fish, but bite the empty one?
This can happen for several reasons: the fish can be passive because of the pressure of the atmosphere or temperature; you can offer it the wrong bait; or the screen is not a fish, but a thermocline or a cluster of plankton. It is also possible that the fish is outside the affected area of your gear, although visible on the screen.
Can I use a sounder in winter from ice?
Yes, most modern sonars can be used in winter, so you put the sensor down the hole, and it's important to make sure that the sensor doesn't freeze to the ice, and some models have a special "winter mode" for cold water.
Does the color of the boat hull affect the sonar readings?
The color of the boat itself doesn't affect, but the bottom material and design can cause interference. Aluminum boats can give echoes from the bottom if the sensor is installed incorrectly. PVC boats are virtually transparent to ultrasound and rarely cause problems if the sensor is rigidly fixed.
How often should the sonar be calibrated?
Sound sounders don't require special calibration, because they use the speed of sound in the water as a constant. But the speed of sound varies with salinity and temperature. Advanced models allow you to manually enter this data to improve the accuracy of depth measurements, but for fishing this is rarely critical.
What to do if the screen goes out in the sun?
If the built-in brightness is not enough, use a visor or canopy over the device. There are also anti-glare films. In extreme conditions of bright sun, it helps to darken the area around the screen with black cloth or use models with matte screens of high quality.