1
Allan K Edwards: Automatic protection apparatus for span lines employed in high speed digital systems. International Telephone and Telegraph Corporation, John T O Halloran, Alfred C Hill, July 12, 1983: US04393493 (77 worldwide citation)

An automatic span line switch for high speed communication lines is disclosed. The apparatus employs an alarm interface unit which is coupled to a service line terminal in order to detect a line failure mode. Upon detection of such a mode, the system operates to modify the parity bit content of the ...


2
Paul J Lima, Todd V Townsend: Automatic span line switch. Lynch Communication Systems, Phillips Moore Weissenberger Lempio & Strabala, September 28, 1976: US03983340 (12 worldwide citation)

An automatic span line switch for PCM communication lines is disclosed which isolates alarm conditions to an actual span line failure, as distinguished from failures in the terminal equipment. In addition, the switch uses a specific code transmission to provide fast switching and to permit identific ...


3
Paul J Lima, Todd V Townsend: Method and means for detecting an outgoing failure in a bidirectional communications span and looping the same in response thereto. Lynch Communication Systems, Phillips Moore Weissenberger Lempio & Majestic, August 16, 1977: US04042794 (12 worldwide citation)

An automatic span line switch for PCM communication lines is disclosed which isolates alarm conditions to an actual span line failure, as distinguished from failures in the terminal equipment. In addition, the switch uses a specific code transmission to provide fast switching and to permit identific ...


4
Clifford A Davidow: Universal high-speed span line switch. Lynch Communication Systems, Weissenberger & Peterson, July 14, 1987: US04680750 (8 worldwide citation)

Malfunctions in an automatic span line switch due to resonances in high-speed span lines are avoided by interposing signal-free intervals whenever the switch causes a possible phase change to occur in the signal being supplied to the span, preventing the transmission of partial signal pulses, and us ...


5
Edwards Allen K: Dispositif de protection automatique pour lignes de transmission dans les systemes numeriques a grande vitesse, Automatic protection apparatus for span lines employed in high speed digital systems. International Standard Electric Corporation, SMART & BIGGAR, May 1, 1984: CA1166773

A.K.Edwards - 3 Abstract of the DisclosureAn automatic span line switch for high speed com-munication lines is disclosed. The apparatus employsan alarm interface unit which is coupled to a serviceline terminal in order to detect a line failure modeUpon detection of such a mode, the system operates t ...