sounder
An electronic device used on a boat to measure the depth of water beneath it. It sends sound waves to the bottom and calculates the distance based on how long it takes for the sound to bounce back.
Aquatic Technology 7–10 (2024)
A NSW Government website
An electronic device used on a boat to measure the depth of water beneath it. It sends sound waves to the bottom and calculates the distance based on how long it takes for the sound to bounce back.