Speed Log

1.The JLN-550 Doppler Sonar is designed to provide ship speed information with higher stability in the dual frequency modes; one using a lower ultrasonic frequency that is adequate to measure the ship’s speed against the ground up to larger depths and the other using a higher ultrasonic frequency that allows the ship’s speed against the water to be measured even in water with tiny bubbles.

The ultrasonic beam is transmitted in the front and rear directions. At the same time, by simply measuring the difference in Doppler shift received signals to detect and eliminate hull motion, such as left and right sway and undulation, to ensure accurate and stable speed data even under the most severe conditions.

The transducer is designed for dual-frequency transmission, but its size is smaller than the conventional models. It can be installed in the position where the bow is least affected by the foam, achieving stable and accurate operation.

By connecting a GPS receiver, the JLN-550 Doppler Sonar Locator displays comprehensive speed information received from the satellite, ensuring highly reliable and accurate positioning.