Baseband CATV decoder with stereo bypass

摘要

A CATV decoder for receipt of television stereo audio includes a shunt path having a 4.5 MHz filter and amplifier for translating the 4.5 MHz audio signal to a modulator thus bypassing the normal audio baseband detector and 4.5 MHz oscillator circuit. A switch acts through an OR gate for selectively enabling the shunt path and normal audio path. Control from the cable head end is provided by a signal to the OR gate for returning operation to the normal audio path if reception is not authorized. In a similar manner, a remote audio mute signal may be supplied to the OR gate by the viewer.