| echo sounder | |
| —n | |
| a navigation and position-finding device that determines depth by measuring the time taken for a pulse of high-frequency sound to reach the sea bed or a submerged object and for the echo to return | |
| echo sounding | |
| —n | |
echo sounder
device used on ships to determine the depth of water by measuring the time it takes a sound (sonic pulse) produced just below the water surface to return, or echo, from the bottom of the body of water. Sonic depth finders are in operation on practically every important class of ship, naval and merchant, and are also used on small craft.
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