I've seen several different types of loudspeaker housing used, from steel, through Bakelite to plywood with a cream coloured leatherette finish. It was also piped into hospitals. A little selector knob and volume control on the wall next to the bed, usually a bit loose, led to either a headphones socket (for the S.G. Brown type headsets) or an outlet for an acoustic tube type headset. The system could also be found in schools.
The oldest window selector boxes that I remember were, as stated, brown bakelite. Initially their rotary selector had for positions, marked A B C D. A little later, they had six-way switches, adding channels E & F. Subsequently, this went up to a ten-way switch and now came in ivory coloured bakelite box.
Black sheathed distribution cables went around the back of nearly everybody's house, and where the two houses joined, a black box was fitted to take the lead-off cable to the house. The black box also contained a 'splitter' on a per channel, per house basis. This maintained the electrical integrity (or correct ballance) of the circuit.
Once in a while, the volume would go low. Then the Rediffusion man would come out to check the boxes, to see who had illegally connected his own loudspeaker onto the system, thus draining all the power due to the miss-match.
Although illegal connections were problem, the system could suffer from 'overhearing', or the bleeding through of the audio from an adjacent channel, and TV channels could suffer from 'ghosting' - a second, fainter image which was offset slightly from the wanted one. This assumes that it was not the sort of interference from foreign TV stations, should good weather and the cricket season ever coincide!
There are still a large number of abandoned relics from Redifussion to be seen in our streets. Apart from cables on walls, to wire wrapped suspended cables, brackets and poles, there are still street junction boxes and green cabinets as a reminder of the network.
Description: Old Redifussion kit in Earlston Road, Wallasey.