The delay equalization of the London-Birmingham television cable system

A systematic method of design for delay equalizers with frequency ranges having a moderate ratio of maximum to minimum frequencies is outlined, and a description is given of the delay equalization of the 3–7-Mc/s carrier channels of the London-Birmingham coaxial-cable television relay system. For the transmission of B.B.C. 405-line television signals, the delay of each channel (as measured by noting he envelope delay of a variable-frequency carrier modulated by a 100-kc/s signal) has been equalized to within ± 0.06 microsec over the frequency range 3–7 Mc/s.