Television channel distribution network

Claim 1

A distribution station for a videocommunication network, the station receiving M television channels 1 . . . h . . . M from a single wideband distribution line and routing the M channels to N subscriber television terminals 1 . . . k . . . N, where M and N are integers, k is selectively each of 1 through N, and h is selectively each of 1 through M, terminal k being connected to said distribution station via a bidirectional wideband transmission medium including a first line carrying one of said television channels from said station to terminal k and a second line carrying a channel address signal from terminal k to said station, said distribution station comprising 1 . . . h . . . M individual channel selectors, each of said selectors receiving said M television channels and continuously selecting a respective television channel, 1 . . . h . . . M video coding means for respectively converting the channels selected by said 1 . . . h . . . M selectors into 1. . . h . . . M digital signals, digital video switching means controlled by said channel address signals in said N second lines, said switching means including 1 . . . h . . . M inputs respectively responsive to said 1 . . . h . . . M digital signals and 1 . . . k . . . N outputs respectively associated with said 1 . . . k . . . N television terminals in response to a respective digital channel address signal carried by the 1 . . . h . . . M inputs, input h being addressed by the digital channel address signal in said second line of the transmission medium including said first line associated with said output, and N video decoding means connected to said switching means outputs and to supply signals to said N first lines for converting the digital signals delivered by said switching means outputs into the corresponding television channels carried by said N first lines, said distribution station comprising a programmable spare selector for receiving said M television channels from said distribution line, spare video coding means for converting a television channel selected by said spare selector into a digital signal, and means for selectively substituting said spare selector and said spare video coding means for a faulty assembly comprising one of said M selectors and one of said M video coding means associated with one of said television channels.