Abstract: An improved security and communication system accurately and quickly locates the position of a signaling portable radio frequency transmitter. When a portable transmitter is activated, a first signal, including identification information, is emitted. The first signal is received by any of a number of radio frequency relays, the signal is manipulated and transmitted to a central processing station as a second signal. The central processing station can, by using the second signals received, either from one or a number of relay stations, determine which relay station is closest to the portable transmitter.

Abstract: A system for moving receptacles such as highway semi-trailers on railway trains. The system includes a plurality of rail bogies as the sole support of adjacent rear and front ends of the trailers and as the sole connection means between the trailers, to form the trains. The rail bogie has a frame structure supported on spaced apart wheeled axles, defining a pair of end deck surfaces positioned above the wheeled axles and a central drop-deck surface disposed between and below the end deck surfaces. A vertically adjustable fifth wheel assembly is supported above each of the end deck surfaces for receipt of a semi-trailer king pin. A deck plate member is pivotally secured to the drop-deck surface. A pair of transversely spaced, longitudinally extending, internal and external rub-rail members extend upwardly from the drop-deck plate member for receipt of semi-trailer tandems therebetween.

Abstract: A security and communication system permits the location of signaling portable radio frequency transmitters which may be carried by individuals. If an individual signals with his portable frequency transmitter, a first signal is sent including a first individual identification code to identify the particular portable transmitter. The first signal is picked up by at least one of a plurality of radio frequency relays each positioned in a predetermined location. Such relays immediately transmit a second signal including the first identification code and also a second identification code to identify the individual relay that is transmitting the second signal. Thus the signal sent by the individual relay identifies the location and the specific identity of the particular portable radio frequency transmitter which is sending the signal.

Abstract: A remote-controlled doorbell adapted for connection across the existing doorbell in a building having a wired doorbell system. A transmitter for generating an over-the-air radio signal is coupled across the wired doorbell so that the transmitter will be actuated in response to current flowing through the wired doorbell. A remote receiver coupled to sound producing means receives the over-the-air radio signal and actuates the sound producing means when the existing doorbell is energized.