Abstract: A wired broadcasting system is provided which comprises a wideband coaxial cable for carrying multi-channel programme signals from at least one programme source to a plurality of exchanges to each of which a plurality of subscriber units are connected. The programme source provides signals on the cable stacked one upon the other in frequency. Each exchange comprises in respect of each subscriber a switchable frequency translator for selectively translating any one of the said stacked frequency signals to a predetermined other frequency which the subscriber unit is adapted to receive, switching means controllable from the respective subscriber unit to selectively switch the frequency translator, and an output circuit arranged to apply the said predetermined other frequency signal to a feeder cable to which the subscriber is connected.