Electronic system for controlling access to television transmissions intended for protection of children and youths against violence and sex

摘要

Electronic system for controlling access to televised transmissions, according to the invention, intended to combat violence and sex on television. Transmissions not for the general public are given a sinusoidal code signal situated in the non-audible low frequencies of the sound signal, between 0 and 100 Hz. This code signal, after having been separated from the useful sound signal by the use of a selective filter, is conditioned before being used by a digital part intended to put the television set on standby pulse train at (6) after a time delay (8) of a few seconds intended to give time for an adult to enter (9), via a keyboard, a numerical code not known to the children and capable of preventing the television set going to standby. The children, not knowing the numerical code, have to switch over to another transmission. IMAGE