Abstract: A telephone line access apparatus includes a first stage for providing high voltage protection and a second stage filter in series with the first stage. The first and second stages are incorporated within a housing that is adapted to plug into an existing main distribution frame of a telephone central office.

Abstract: A line access apparatus for in-band communication includes a line coupler that functions as a high voltage isolation device and has a resonant frequency out of the signal transmission band. A carrier signal of about the resonant frequency is modulated at an in-band frequency to convey information across the line coupler.

Abstract: A telemetry system connects with a telephone system for communication of data via subscriber telephone lines to a provider of data services. Connection of multiplexing circuitry to a set of subscriber lines is accomplished at a main distribution frame by adapters or access blocks set between arc suppressors and a terminal block. The multiplexing circuitry is activated by signals of a line scan unit which, in turn, cooperates with a host computer associated with a station wherein data is processed. The data may be transmitted out of voice band, if desired, to enable simultaneous voice and data transmission. Passive, active and interactive data can be transmitted by the telemetry system. The host computer selects which of a plurality of stations is to be coupled to which of a plurality of subscribers.

Abstract: A data transport system connects with a telephone system for communication of data via subscriber telephone lines to a provider of data services. Connection of multiplexing circuitry to a set of subscriber lines is accomplished at a main distribution frame by adapters or access blocks set between arc suppressors and a terminal block. The multiplexing circuitry is activated by signals of a line scan unit which, in turn, cooperates with a host computer associated with the provider of data services. This arrangement bypasses the central switching equipment. The data may be transmitted out of voice band, if desired, to enable simultaneous voice and data transmission. Passive, active and interactive data can be transmitted by the data transport system.

Abstract: A system for providing remote services and maintenance functions includes a voice subsystem adapted to receive voice and DTMF signals that can be used to control the execution of a plurality of service and maintenance tests. The system also includes a programmed control subsystem that provides voice based response and conveyance of results of such maintenance services and tests to field personnel.

Abstract: An apparatus for collecting and forwarding encoded information includes a source of power maintained from the output port thereof to provide power to the source of encoded informations whereby a local subscriber is not required to supply power to such encoders via the AC mains to his premises.

Abstract: A test trunk access controller includes a test trunk interface controller accessed by a subscriber line assigned to a service provider, or other remote metering facility, and a test trunk interface device inter-connecting the test trunk controller with the test trunk device of a local telephone switch.

Abstract: A system is presented for accessing a plurality of central office lines, PBX, etc. by a plurality of stations and for exchanging signals between the stations. Each station is provided with a self-sufficient microprocessor which controls all the functions of the station. The microprocessors exchange control signals to indicate the status of each station and each line. A common intercom line is provided for both audio signals and control signals. Each station is assigned a unique address so that each station is able to dial up another station for intercom communication by generating the proper control signals.Each station is also provided with a switch matrix for selectively accessing any of the lines, line status indicating means, and line holding means which is automatically released when any station accesses the held line.

Abstract: A system for transporting data between equipment connected to a subscriber telephone line and a provider of services connects with subscriber telephone lines at a central office of a telephone company. The system includes a set of first multiplexers which are coupled to individual ones of the subscriber lines at a point between the cross-switching of the central office and the subscriber premises. Output signals of the first multiplexers fan into a second multiplexer. Bidirectional communication is provided between each of the multiplexers and the subscriber equipment, and also between the second multiplexer and the service provider via a line scanner which generates command signals for the operation of the first and second multiplexers. The first multiplexers, the second multiplexer, the line scanner and a host computer of the service provider can be located at a distance from each other and may be coupled together by communication links which permit the bidirectional flow of data.

Abstract: A time-division multiplexed switching system is disclosed with a transmit, and a receive bus. Communication ports are provided for transfer and conversion of signals between the lines and the buses. A control microprocessor is used for assigning appropriate time slots and for strobing the communication ports at appropriate times. The time slot interchange between the two buses is provided by a half-frame delay network. The slots assigned to a particular interconnected pair of communication ports differ by a half-frame period to provide full duplex operation.

Abstract: A system for accessing telephone lines at a main distribution frame includes an access block positioned between a vertical input terminal block and protector modules of the distribution frame. The access block has a set of terminals which make direct connection between the corresponding terminals of the input and protector modules and, in addition, includes a printed circuit with individual conductors coupled to respective ones of the access block terminals. Multiplexing circuitry connects with the printed circuit for sequential coupling of messages among the various telephone lines passing through the access block. Additional multiplexing circuitry is located on the distribution frame at a site remote from the input blocks and is coupled to the multiplexers associated with each of the input blocks to scan through the output signals of each of the multiplexers.

Abstract: An access device is provided for a main distribution frame of a telephone system. The access device, which may be structured as a set of access blocks, is positioned between surge protection modules and their corresponding vertical input terminal block so as to make electrical contact with the subscriber telephone line without interruption of the array of harnesses which couple together the various terminal blocks of the main distribution frame. A printed circuit contained within each of the access blocks comprises conductors which contact feed-through terminals of the access block, the conductor coupling these terminals to multiplexers which provide for the selective coupling of messages from the subscriber lines to the subscriber line of a message receiving station.

Abstract: A circuit for adapting a telephone subscriber line to operate as a multiparty line is described wherein a plurality of conventional single line subscriber subsets are provided telephone service on the subscriber line such that each subscriber has privacy at all stages of call progress. In accordance with another feature of the present invention, frequency selective ringing is not required to prevent ringing from occuring at other subscriber subsets on the multiparty line when a party is called. The circuit of the present invention controls the switching of battery polarity at the central office to connect and disconnect subscribers from the line. The invention further provides automatic telephone number identification when calls are initiated by varying a unique identity tone for billing purposes. The invention also uniquely provides for user transparent reverting calling such that no special dialing procedure is required to make reverting calls and complete privacy is maintained, even on reverting calls.