A signal distribution system is described for the interchange of signals between a number of appliances such as television receivers 13, 14, video recorders 15 and surveillance cameras 16, 17, 18. The appliances are connected via a passive star splitter 1. A controller 11 allocates frequency channels to each appliance. The system is such that signals within a particular frequency channel injected into the system by one of the appliances may be received by any receiver appliance connected to the system to which has been allocated the same frequency channel.