L3 coaxial system - Equalization and regulation

Abstract

The equalization and regulation problems of the £3 system are described and a theori] of equalization of complex systems is outlined. The location and function of the various equalizers are explained including the roles and design of the various fixed, dynamic and manual equalizer networks. The analog computer used in the regulation system is described together with the cosine-equalizer adjusting technique used with manual equalizers. Finally the circuits and operation of the regulation system and its components are presented.

Residual attenuation equalisation of broadband systems by generalised transversal networks

“…At this point, it is perhaps appropriate to study the frequency dependence of the approximation available from two well known scales, the linear frequency scale of echo waveform correctors, 7 and the slightly warped scale of the first cosine equaliser, which was designed at the Bell Laboratories. 4 For a cosine equaliser with a linear frequency scale ranging from zero to an upper frequency limit f h , The recorded slope distributions are fairly well bounded at medium and high frequencies, but at the low-frequency end, say below 250kc/s, the limit is exceeded by a factor approaching 50. Clearly, the frequency scale on which the limit is based is inappropriate in the illustrated case, and something quite different is required.…”

“…This inclination is strengthened by the complicated array of adjustment instrumentation described in the literature for cosine equalisation. 4 However, careful consideration shows cosine equalisation in a more favourable light. The question can be approached from various points of view, of which not the least important is the reaction of the operator in the field.…”

“…This has been pointed out in the literature together with other reasons for preferring cosine equalisation, some of them connected with the orthogonality of harmonic cosine shapes. 4 It is only fair to say that the orthogonality is partly lost when producing large shape amplitudes with certain transversal networks, which offer, on the other hand, great practical advantages. * There may be exceptional circumstances, see Reference 4 340 3…”