BBC final amplifier valve

A large mercury based valve from the former BBC Borough Hill site which opened in 1925 in DaventryThis is a large water-cooled valve from the former BBC Borough Hill site which opened in Daventry in 1925 with the first 'long wave' National Broadcasting Station known as 5XX. The radio announcement of 'Daventry Calling' was made at the opening and became well known across the world. Daventry was chosen for the site as it was the point of maximum contact with the land mass of England and Wales. In 1932, the 'short wave' Empire Service commenced broadcasting later developing into the BBC World Service. The station was also instrumental in the development of Radar and the 'G' system for bomber command navigation and homing device during WW2. The BBC final amplifier valve illustrates the importance of radio and other radio systems that have had global resonance.

A large mercury based valve from the former BBC Borough Hill site which opened in 1925 in Daventry