This chapter reviews the development of television technology, focusing on the work of John Logie Baird. The author introduces this chapter by discussing the technology of cameras and photography, facsimile, moving pictures, and the television system.

In 1966, as part of the 30th anniversary of the start of 405-line television, research work unveiled a disc held in the BBC Sound Archives. This contained a recording in the 30-line Baird video format. BBC engineers used the best equipment available to get pictures off the disc. With the benefit of audio filter banks, phase correction equipment and special hardware to drive an electron tube display, they managed to get several photographs of single pictures from the discs. The results were good and caused great excitement.

Prior to the 1980s, no-one had been promoting the Phonovision discs as being of any value, historic or monetary. Their content was unknown and their significance not realised. As such, they were unlikely to be deliberate fakes. Nevertheless, the author needed to determine whether the discs were genuine or not, rather than leave any question of their authenticity open. Fortunately, at least one of the discs is traceable through paperwork right back to 1928. This is the disc that Baird had donated to the Science Museum, as recorded via its Museum catalogue number. Baird had also donated another Phonovision disc to the Television Society. However, the Society had not recorded evidence of the disc's pedigree. Indeed, for many years, an early notary of the Television Society, Barton Chappie, had kept the disc and other precious items in safe keeping, away from Central London and the threat of German bombs during the Second World War.

The demonstration of 30-line television reception across the Atlantic in February 1928 indicated that the low definition signal would travel well. With Baird's television service from 1929 and the BBC's service from 1932, various experimenters found that the television programmes from the BBC transmitters could be received over vast distances. There was nothing magical about this; it had to do with the natural long-distance propagation of medium-wave transmissions, especially in the hours of darkness.

Television has only been around for a matter of decades. You would think then, that with such a short history, what there is of it ought to be reasonably correct. However, as we take new views, particularly on who did what, first, we continually re-visit, re-assess and revise the early history of television. These changes are more often to do with developing opinions, driven by either cultural changes or personal and political agendas, rather than new information brought to light. This effect is, of course, universal and is neither limited to television nor indeed to Britain. The USA, for example, has had its television history re-appraised recently.