TV system for image and data transmission - inserts digital sound data packets in line suppression internal of transmitted signal and recovers them in receivers

摘要

The television system has a transmitter which includes a circuit for generating a line and frame image or information signal (40), each line comprising a line suppression interval followed by a processing interval containing the image or information signal. A circuit (50,52) samoles the sound and generates a digital signal for each sampling value, and a leading digital signal is derived from a sound synchronising signal. The leading signal is followed by the sound digital signals being inserted in preselected spaces in the line suppression intervals. Each television receiver has a sound extraction circuit which extracts the sound digital signal and converts there to an analogue signal.