Abstract: An auto-answer videotex terminal includes data signal transmission and processing circuits and an isolating transformer between them and a telephone network. It also includes circuits for detecting and recognizing the ringing signal from the network which are connected to the network by the isolating transformer for the data signal circuits. A capacitor and an attenuator resistor appropriate to the frequency and the level of the ringing signal transmitted by the network are associated with the data signal circuits. Further, selectively operated circuits bypass the attenuator resistor and reduce the impedance of the capacitor when the ringing signal is recognized.