The BBC-Marconi Type B
Technical note by Chris Owen, senior BBC engineer
About four inches in diameter, this ribbon mic was brought into service in 1937. It was made possible by the use of Alnico alloy (aluminium-nickel-cobalt) for the magnet, which allowed a small circular magnet to be used rather than the large horseshoe-shaped magnet of the BBC Marconi Type A mic. It became popular for BBC OBs and for sports commentaries. It could be fitted to a breastplate that was worn by the commentator and ensured that the mic was always facing him if he turned to follow the action. This was not totally successful with some commentators but it ultimately led to the development of the L1 lip mic in the same year. The breastplate continued to be used, but in the form of a harness to hold the lip mic thus giving the commentator hands-free operation.
Dicky Howett comments: This is my BBC-Marconi Type B ribbon mic. This type was used extensively by the BBC during WW2. My example is dressed with a BBC badge although the actual mic was used by the International Broadcasting Company in its London recording studios from 1938 through 1950.
All photos are courtesy of Dicky Howett.