| 摘要 |
The present invention aims to substitute for the very slow and expensive development of entirely new networks for distributing so-called "cable" television and associated programmes, with coaxial or fibre optic cables, the straightforward new application for this purpose, of networks already in service for other purposes, for example, for the telephone and better still for the distribution of electricity, by virtue of novel combinations of means and methods which are mutually appropriate, applying, on the one hand, the elimination of "very high or ultrahigh frequency carriers" so as to transmit at "medium or low frequencies" only the so-called "picture video and sound" signals and their "synchronising pips" after ordinary processing operations, as well as self-monitored amplification and original so-called "analog to digital" transcoding, whilst, on the other hand, the simultaneous conveying through the same cables, of the signals for several "programs", by means of appropriate "filters", is carried out for example with the technique customary in telephony and termed "carrier currents", but here again applied in a new way.
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