Abstract: A masthead control system and method are provided for a sailing vessel to reduce the number of cables running inside the mast to a single coaxial cable carrying power, control and data signals, and VHF radio signals. The coaxial cable connects an antenna directly to a VHF radio communications device such that radio communications are always available in case of emergency. The system comprises an instrumentation center that connects to the masthead; at least one masthead device that connects to the instrumentation center; and a cable, such as a coaxial cable, that connects the instrumentation center to an interface unit located in the hull. The cable carries power, at least one radio frequency signal, and at least one data or control signal between the instrumentation center and the interface unit.

Abstract: A switch that couples transducer signal to a specific sounder of multiple sounders in response to a sensed signal from the specific sounder. The switch can include a first detection circuit that determines the sounder that is requesting the first transducer signal and a first control circuit that couples the first transducer signal to the requesting sounder. The switch can further include a second detection circuit that determines the sounder that is requesting the second transducer signal and a second control circuit that couples the second transducer signal to the requesting sounder.

Abstract: An acoustic system and a method for repelling marine mammals from a region of water is disclosed. A plurality of acoustic transducers (10,12,14,16) are spatially dispersed beneath the surface of the water. The transducers (10,12,14,16) in sequence output high frequency acoustic signals into the water. The power of the acoustic signals starts at a low level and is gradually or incrementally increased to a high level which produces a signal beyond the threshold of pain of the mammals to be repelled. The mammals are therefore gradually repelled from the area without suffering permanent hearing loss.

Abstract: A marine speedometer for mounting to the exterior transom of a marine vessel includes a housing mounted to the transom flush with the bottom surface of the hull. A paddlewheel affixed to the housing has an outer periphery which extends no further than the bottom surface of the hull of the marine vessel. A portion of the housing adjacent to the bottom surface of the hull is shaped to direct a flow of water passing by the transom upwards into the paddlewheel to rotate the paddlewheel.

Abstract: A marine speed sensor mounted in a housing which may also include a temperature sensor and a sonic transducer. The speed sensor includes a paddlewheel for producing an electromagnetic field. The paddlewheel is rotatably mounted adjacent the housing and exposed at top and bottom and mounted between support members extending from the housing.

Abstract: A marine speed sensor mounted in a housing which may also include a temperature sensor and a sonic transducer. The speed sensor includes a paddlewheel for producing an electromagnetic field. The paddlewheel is rotatably mounted adjacent the housing and exposed at top and bottom and mounted between support members extending from the housing.