Video-telephone system initially signifies caller to called subscriber

In a video-telephone system comprising a switching network and subscriber stations each including a telephone handset and an associated audio bell actuated by a ringing tone signal, a television camera, a television receiver and a character generator, and connected to said switching network by a bidirectional telephone line and by an incoming and outgoing unidirectional video line conveying video signals, the improvement allowing a called subscriber to receive on his television receiver, before he has taken off his telephone handset, characters transmitted by a calling subscriber, the said improvement comprising in each subscriber stations means controlled by the handset taking off for connecting the character generator to the outgoing video line, means controlled by the handset taking off for supplying with current the television camera, means for detecting the ringing tone signal on the telephone line, means controlled by said ringing tone signal detecting means for supplying with current the television receiver, means for detecting the video signals on the incoming video line and means controlled by said video signal detecting means for connecting the television camera to the outgoing video line.