NorthStar Navigation 491 Glossary, Cavitation Deadrise Echo sounder Fairing block Transducer

Glossary

cavitation

deadrise

echo sounder

fairing block

transducer

The formation of bubbles, which may negatively impact a transducer’s readings by reducing its ability to put energy into the water.

The rise of the bottom of a vessel above a horizontal line at the center of the vessel; that is, the slope of the hull away from the horizontal.

An instrument that uses sound waves to measure the depth of a body of water or an object (such as a school of fish) below the water’s surface.

A block used to create a horizontal surface for mounting a thru-hull transducer when the vessel’s deadrise is more than 5 degrees.

The device mounted through the hull to send and receive ultrasonic beams that determine seabed conditions and locate fish. Essentially, a transducer is an energy converter, which changes electricity to sound (send) and sound to electricity (receive).

water column An imaginary column through the water created by the path of a single transducer ping and its echoes.

491 INSTALLATION MANUAL Revision A PAGE 29