The Echo Sounder

The echo sounder is a device used in shipping for the electroacoustic measurement of water depths (sounding). The time that elapses between the emission of a sound pulse (water-borne sound) and the arrival of the sound waves reflected from the seabed is measured. It is useful to distinguish between echo sounders for safe navigation, those for surveying purposes for creating sea charts and determining the need for dredging, in particular of waterways, and research echo sounders.