[psyentist]

I can tell you a bit about a system that was introduced in the mid 60s in Woolwich & Plumstead, South-East London.

It was originally called "Woolwich relay" and was a system to get around the fact that the area was in the shadow of Shooters Hill, thus effectively blocking signals from Crystal palace (BBC) & Croydon (ITV).

Initially it was VHF (405 lines) and offered three channels - BBC London, ITV London and ITV Anglia. Some people (including my father) had previously erected aerials pointing to the Anglia transmitter at Mendlesham to get a watchable ITV signal.

Later it was converted to UHF (625 lines) to accommodate BBC2 transmissions including colour. This required a total upgrade to the cabling & repeaters - the latter made by Teleng.

I believe the system was based on a similar operation in Canada. My father was the main service engineer and we left London as a family in 1969 so not sure what happened after that.

I do know the cable network was later operated by Greenwich Cablevision.