Coaxial cable including at least one repeater

Claim 1

A coaxial cable comprising center steel wires; an inner conductor coated uniformly on the center steel wires; an outer tubular conductor, an inner insulator filled between the inner conductor and the outer tubular conductor; an outer insulator coated on the outer surface of the outer tubular conductor; and repeater means comprising at least one unreflective section of wave absorbing material provided in the inner insulator, a wide band amplifier embedded in the inner insulator and actuated by a dc difference between two opposed ends of a cut portion in the inner conductor and the center steel wires for amplifying a transmitted signal derived from one side of the unreflective section and for applying the transmitted signal to the other side of the unreflective section; two high pass filters having the same cut-off frequency and inserted respectively between the input of the amplifier and said one side of the unreflective section and between the output of the amplifier and the other side of the unreflective section, and two low pass filters having the same cut-off frequency as that of the two high pass filters and inserted respectively between the input of the amplifier and the other side of the unreflective section and between the output of the amplifier and said one side of the unreflective section, coupling means comprising insulating material and disposed at the cut portion for coupling said two opposed ends of the cut portion of the inner conductor and the center steel wires in a spacedapart relationship comprising a pair of coupling members coupled respectively to said two opposed ends, a plurality of first parallel elongated branch rods coupled at one end portion thereof to one of the coupling members, a plurality of second parallel elongated branch rods coupled at one end portion thereof to the other of said coupling members, and means separating said first parallel branch rods from said second parallel branch rods including first spacing members and second spacing members fixed separately in the inner insulator and coupled to portions of said first plurality of parallel branch rods and said second plurality of parallel branch rods respectively to maintain the branch rods in a fixed spaced apart position with respect to each other.