I cheated a bit last week, so this week I thought I’d better bring out a proper, genuine gem. This is the last ever broadcast on the 405-line system, on 3 January 1985.
To mark the occasion, the BBC brought out a 1938 television set (that would be a Baird Model T18 for you anoraks out there!) that was picking up BBC One as it was being transmitted from Crystal Palace. This was broadcast live to the nation during that evening’s closedown.
A full recording of the T18’s output, capturing the final moments of 405-line transmission, also lives on.
625-line broadcasts began in 1964 with the advent of BBC Two. BBC One began to make the switch in 1969. It took some time for the new system to reach the high levels of coverage achieved by 405-line, despite there being many more transmitters.
As such, the switchover period from the first public 625-line broadcast to the 405-line closure was 21 years. A further 27 years on, the 625-line service will be closed when digital switchover is completed in 2012.
You will note that the BBC One continuity announcer refers to 625-line broadcasting as “high definition”. The 405-line system was also originally billed as “high definition”.