Television frequency-translating terminal equipment for the Birmingham-Holme Moss coaxial cable

The paper opens with a discussion of the various factors affecting the performance of vestigial-sideband systems, and the reasons for the choice of carrier frequency and width of the vestigial sideband used on the Birmingham-Manchester television link operating over a standard 0.375-in diameter coaxial cable. A description then follows of the double-modulation method by which the vision signal is converted into a modulated wave having a carrier frequency of 1.056 Mc/s and a vestigial-sideband width of 500 kc/s. After passing over the repeatered cable the vision signal is restored at the receiving terminal to its original position in the frequency spectrum. Descriptions are then given of the electrical and mechanical details of the transmitting and receiving terminals, special attention being given to the design of the modulators and band shaping filters. The paper concludes with a brief discussion of future trends in the design of terminal equipment.