1
Hachenburg Victor: Loop data transmission arrangement employing an interloop communication terminal. Bell Telephone Laboratories Incorporated, Albrecht J C, June 17, 1975: US3890471 (48 worldwide citation)

A data transmission arrangement comprising a plurality of data transmission loops wherein pairs of data transmission loops are interconnected by an interloop communication terminal. An interloop communication terminal comprises means for monitoring messages received on one loop of the pair to which ...


2
Smith Nicholas Kimbrough, Truesdale James Bartel: Redundant data transmission arrangement. Bell Telephone Laboratories Incorporated, Albrecht J C, January 7, 1975: US3859468 (45 worldwide citation)

A loop data transmission arrangement is disclosed in which a plurality of transmission terminals are serially connected to a base terminal by a primary transmission line and a secondary transmission line over which time-divided data signals are transmitted in opposite directions by the base terminal ...


3
Cook Robert Wilcox: Microprogram controlled data processor for executing microprogram instructions from microprogram memory or main memory. Bell Telephone Laboratories Incorporated, Albrecht J C, January 7, 1975: US3859636 (32 worldwide citation)

A microprogram controlled data processor for executing microprogram instructions from the microprogram memory or from the main memory having a control unit, a random access readable and writable main memory containing main program sequences and data, and a random access read-only microprogram memory ...


4
Bonser Richard Harlan, Willett Robert Joseph: Fault detection arrangement for digital transmission system. Bell Telephone Laboratories Incorporated, Albrecht J C, October 21, 1975: US3914741 (29 worldwide citation)

A digital information transmission system includes a control unit for transmitting digital words each including an address, message, and an error detecting code derived from the address and messsage to a plurality of uniquely addressable peripheral units over a common bus. Each peripheral unit inclu ...


5
Fulton Alan William: Integrated circuit memory cell. Bell Telephone Laboratories Incorporated, Albrecht J C, September 30, 1975: US3909807 (21 worldwide citation)

A cell for an integrated circuit memory is formed of two interconnected identical halves. Each such half is integrally formed without surface metal interconnections. The memory is fabricated from a semiconductor body which comprises an epitaxial layer of one conductivity type overlying a semiconduct ...


6
Casterline Russell Carson, Krawiec Zbigniew Apoloniusz, Peterson Ralph Broman: Switching system equipped with line verification apparatus. Bell Telephone Laboratories Incorporated, Albrecht J C, July 1, 1975: US3892928 (9 worldwide citation)

An arrangement for verifying the accuracy of connections of customer lines to an electronic switching system which is a replacement for an existing switching system is disclosed. More specifically, an electronic switching system is disclosed comprising one or more test trunk circuits, each connected ...


7
Wiley Paul Ronald: Periodic pulse check circuit. Bell Telephone Laboratories Incorporated, Albrecht J C, September 2, 1975: US3903474 (8 worldwide citation)

An error checking circuit for checking periodic pulses for the absence of a pulse or the presence of a spurious pulse. A sequence of periodic pulses is passed through an inverter gate delay line having outputs available from each gate in the delay line. The outputs from even-numbered gates are conne ...


8
Danielsen Daniel, Ketchledge Raymond Waibel: Reed switch communication network ensuring open contacts before closure. Bell Telephone Laboratories Incorporated, Albrecht J C, January 7, 1975: US3859471 (3 worldwide citation)

A switching network is disclosed which employs magnetically operated sealed reed switches having reeds of a remanent magnetic material. Circuitry is included in the control portion of the network to preclude the possibility of sticking contacts. This circuitry provides for generating magnetic fields ...


9
Ault Cyrus Frank: Line supervisory circuit. Bell Telephone Laboratories Incorporated, Albrecht J C, June 10, 1975: US3889069 (3 worldwide citation)

A line supervisory circuit for determining the on-hook or off-hook status of a subscriber line subset responsive to current in the subscriber line. The line supervisory circuit includes a magnetic element having drive windings, interrogate windings, and sense windings. A magnetoresistor is connected ...


10
Taylor Frank Finley: Line searching arrangement having priority sequence. Bell Telephone Laboratories Incorporated, Albrecht J C, November 26, 1974: US3851310 (2 worldwide citation)

A line search arrangement for determining if a preselected condition exists on any of a plurality of lines which responds to information request signals from a control unit by transmitting to the control unit the location of the first line, in accordance with a predetermined sequence, exhibiting the ...