Picture/audio signal transmission system

摘要

A center-to-end type information service system utilizing the public telephone networks that are fundamental communication media of nation-wide scale is disclosed in which desired information is requested from the terminal side to the center by means of a telephone set or simplified keyboard and then delivered to and received by a TV receiver. A part of the center functions is transferred together with the exchange function to a subcenter located near the terminal. Thus, the length of transmission path connecting the center to terminals becomes shorter and the cost of the whole system can be cut down.