Abstract: An optical data communication and location apparatus for at least one location in a facility having at least one receiver at said at least one location. A plurality of portable transmitters provides optical wireless data links with the receiver. Each of the transmitters has a power supply with circuitry for transmitting data packets over said optical wireless data links to the receiver. The circuitry for transmitting data packets generates a data code having at least two time frames, each of the at least two times frames being divided into at least two data time slots. Each frame has exactly one pulse in one data time slot whereby in each data packet, there is encoded n-bits of binary data where 2.sup.n is equal to the number of time slots in each frame.

Abstract: An optical data communication and location apparatus for at least one location in a facility having at least one receiver at said at least one location. A plurality of portable transmitters provides optical wireless data links with the receiver. Each of the transmitters has a power supply with circuitry for transmitting data packets over said optical wireless data links to the receiver. The circuitry for transmitting data packets generates a data code having at least two time frames, each of the at least two times frames being divided into at least two data time slots. Each frame has exactly one pulse in one data time slot whereby in each data packet, there is encoded n-bits of binary data where 2.sup.n is equal to the number of time slots in each frame.

Abstract: An optical data communication and location apparatus for at least one location in a facility having at least one receiver at said at least one location. A plurality of portable transmitters provides optical wireless data links with the receiver. Each of the transmitters has a power supply with circuitry for transmitting data packets over said optical wireless data links to the receiver. The circuitry for transmitting data packets generates a data code having at least two time frames, each of the at least two times frames being divided into at least two data time slots. Each frame has exactly one pulse in one data time slot whereby in each data packet, there is encoded n-bits of binary data where 2.sup.n is equal to the number of time slots in each frame.

Abstract: Personnel locating system for use in a facility having a plurality of rooms having doorways therein comprised of a plurality of portable transmitters. Each of the transmitters includes a battery and each generates an infrared signal. The system also comprises a plurality of fixed receivers positioned to cover different rooms at a facility. Each room has a receiver therein positioned to accept infrared radiation from a substantial portion of the volume of the room. Each receiver is capable of sensing and storing any of the infrared signals generated by the transmitters during any time the transmitters are located anywhere in the facility including when located within a room. The system also includes apparatus for polling the receivers to determine the location of any transmitter independent of the previous location of the transmitter.

Abstract: Controller for use at a listening station in an audio distribution system for selecting a channel of audio programming. The controller has input attenuators for reducing the level of the audio signals, an output amplifier, and a controlled analog switch connected between the attenuators and the amplifier for passing the attenuated audio signal from a selected channel to the output amplifier. The amplifiers have a relatively high imput impedance, and the amplifiers in the distribution system operate at a relatively low power level. The attenuated audio signals are impressed upon a voltage centered in the operating range of the analog switch. In the disclosed embodiment, the analog switch comprises a multiplexer, a counter connected to the address inputs of the multiplexer, and a channel selection switch for applying clock pulses to the counter to step the multiplexer through the audio channels in a predetermined sequence.

Abstract: Computer controlled, multiplexed hospital signaling and communications system. All station functions are controlled by a computer in a central station which continuously interrogates the other stations to verify that the system is functioning properly and to determine what actions are to be taken. The system includes a plurality of buses connected to the master station, with a plurality of remote stations with peripheral devices connected to each of the buses. A plurality of master stations can communicate with any of the remote stations on any of the buses. Time domain multiplexing is employed in the transmission of both data and audio signals in the system.

Abstract: Call switch for use by hospital patients and staff members to summon aid in wet areas such as shower and bath areas. An actuating magnet is positioned on the front side of a waterproof panel for controlling the operation of electronic circuitry mounted in a dry area behind the panel. The magnet is carried by a slide for movement between rest and tripped positions, and a pull cord is connected to the slide by a breakaway member which permits the cord to separate from the slide when a patient becomes entangled in the cord or the pull on the cord otherwise exceeds a predetermined limit.

Abstract: Personnel locating system for use in a facility having a plurality of rooms having doorways therein comprised of a plurality of portable transmitters. Each of the transmitters includes a battery and each generates an infrared signal. The system also comprises a plurality of fixed receivers positioned to cover different rooms at a facility. Each room has a receiver therein positioned to accept infrared radiation from a substantial portion of the volume of the room. Each receiver is capable of sensing .[.and storing.]. any of the infrared signals generated by the transmitters during any time the transmitters are located anywgere in the facility when located within a room. The system also includes apparatus .[.for polling.]. .Iadd.coupled to .Iaddend.the receivers to determine the location of any transmitter independent of the previous location of the transmitter.