The working principle of the echo sounder

To go fishing, you must first understand how the depth sounder works

Operators need to know how to adjust settings, change frequencies, split screens, zoom bottoms, and control how signals are recorded and presented on the display. After learning these techniques, the information recorded on the display screen makes more sense - and you can apply your fishing skills.

How an echo sounder works

An echo sounder is a device used by fishermen to determine water depth, the presence of fish, and the presence and nature of bottom structures. It does this by transmitting sound waves through a transducer into the water column at selected frequencies. The sound waves hit the target - fish or bottom structure - and echoes bounce off the target back to the sensor's receiver. The return signal is then processed and recorded on the display.

Factors that affect the work of the echo sounder

1. The influence of ship swaying on the work of the echo sounder

When the ship rolls, the transmitting transducer is also tilted, and the direction of the main beam it transmits changes accordingly. If the tilt angle is not large, the reflected echo of the main beam can still be received by the receiving transducer. When the tilt angle is larger than a certain limit value, the phenomenon of "missing" of the echo signal may occur. In severe cases, all echo signals disappear, and the echo sounder cannot work.

2. The influence of bubbles in water on the depth sounder

The influence of bubbles in seawater on the work of the echo sounder is mainly reflected in two aspects: one is that the bubbles in the water have a weakening effect on the sound energy, and the other is that a large number of bubbles will cause sound reverberation, which will seriously interfere with the normal operation of the echo sounder.

3. The influence of ship speed on the depth sounder

When the ship sails at high speed, the hull vibrates violently, and the water flow violently impacts the hull, resulting in increased interference noise. The cavitation phenomenon of seawater also increased significantly, resulting in weakening of the echo signal. In severe cases, the echo signal will be "submerged" by the interference signal, making the echo sounder difficult to work or even unable to work. Choosing an appropriate transducer mounting location will help reduce this effect.

4. The influence of the attachments on the working surface of the transducer

The attachments on the surface of the transducer have a strong absorption effect on sound energy, especially when the transducer is not used for a long time, there will be a large number of sea creatures growing on the surface, which has a great impact on the work of the transducer. Therefore, the working surface of the transducer should be cleaned in time. Also note that the working surface of the transducer cannot be painted.

5. The influence of seabed bottom and slope Different seabed bottoms have great differences in their ability to reflect sound waves. Rock is the strongest, followed by sand bottom, and silt is the worst. In order to achieve the best display effect of the monitor, the sensitivity of the echo sounder should be adjusted according to different seabed sediments.

In addition, uneven seabed substrates and seabed slopes will cause the reflected echoes to arrive at the receiving transducer one after the other, resulting in a wider signal band on the display. In order to ensure the safety of the ship's navigation, it is advisable to read the water depth at the leading edge of the signal strip at this time.