Fascinating Blog. It brought back memories of when in 1962 I was a trainee engineer at the then ATV studios and working in the Studio D Anna mentions. There was a 'buzz' of creativity there at that time too with four multi-standard studios in action making shows for not only ITV network but for America too and it was not unusual to have one studio rehearsing for a live drama, another producing 'Emergency Ward Ten' also live and another studio running on the NTSC 525 line standard recording a musical show for the States. (there was a special power house opposite CAR generating 60 cycles mains for the technical equipment!). Whilst  I was there the ATV Standards Converter was the Backup for the BBC showing the first Transatlantic relay via satellite received at Goonhilly Down.