Abstract: A person monitoring system, such as a baby monitor a monitored unit including a microphone for transducing radiated sound waves and sound waves emanating from the person to a received audio signal and circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide an audio signal corresponding to the sound waves emanating from the person.

Abstract: A horn assembly for installation within an opening in a boat structure having an exterior surface and an interior surface, is disclosed. The horn assembly includes a noise generator component whose output is directed through a trumpet member having an inlet section and an outlet section. A flared element adapted to extend through the opening in the boat structure has an inner end connected to the trumpet member and an outer end with a peripheral flange that bears against the exterior surface surrounding the opening. A grille element extends over and secures the flared element and thus the horn assembly to the boat structure leaving only the grille element visible on the boat exterior.

Abstract: Direct voice communication with simultaneous two-way transmission is possible with a communicator having the earpiece of the communicator at one station connected by flexible plastic tubing to the mouthpiece of a communicator at another station, the two stations being connected by two independent voice channel tubes. The provision of cross-connected channels between the mouthpiece and the earpiece of two communicating stations permits normal conversation with simultaneous two-way transmission to occur in the manner of telephonic transmission rather than requiring sequentially alternating transmission between stations as necessary in using single voice tube communicators where destructive interference occurs between sound waves transmitted simultaneously in opposite directions in a voice tube.