Abstract: The present invention relates to devices for searching for and detecting fish in the water and is suitable for personal use when fishing. A portable echo sounder comprises a submersible unit and an above-water electronic unit connected to each other via a sealed conductive cable. The submersible unit comprises a signal transducer sensor and an autonomous power source connected thereto. The above-water electronic unit comprises a voltage converter, a sensor control unit, a signal processing unit, a signal interpretation unit and a display connected in series. The signal interpretation unit is connected to each of the other units of the above-water electronic unit. The signal transducer sensor and the autonomous power source of the submersible unit are connected to one end of the cable, and the sensor control unit, the signal processing unit and the voltage converter are connected to the other end of the cable.