BBC Marconi AXBT ribbon microphone, inst. no. 498044, made by Marconi's Wireless Telegraphy Company Limited, Chelmsford, Essex, England, 1944-1959.

The AXBT microphone was the fourth generation of Marconi’s ‘Type A’ microphones. Used widely by the BBC from the 1930s onwards, the Type A came to symbolise the BBC. The development of the Type A followed from a similar ribbon microphone that was already in use in the United States, developed by the RCA Corporation. However, it was too expensive for the BBC to buy in the RCA microphones so as an alternative they worked with the Marconi company to develop their own example. There was some concern that the Type A had infringed patents for the RCA ribbon microphone, but these were overcome. The ribbon microphone was good in studio situations, and the AXBT featured improvements to the original designs that made the microphone very sensitive and especially good for use with voice.