Abstract: A communication unit comprised a first and second splitting/combining device, each having terminals for receiving and transmitting a CATV signal and a data signal, respectively, means for combining the CATV signal and the data signal and a third terminal for receiving and transmitting the combined signal. The first terminals of the splitting/combining devices are interconnected through a device for extracting said CATV signals and each of the second terminals is connected to a switch controlled in such a way that the second terminals are either connected to each other directly or connected to a connection device for connection to a computer. The data signal can bypass flats desiring no data connection. Also, the communication unit may be implemented in two parts: one wall mounted part and one adapter connectable to the wall mounted part and comprising the connection unit, which is needed only where a data connection is wanted.