@Cad Delworth said:
@El_Heffe said:They should have a giant vacuum tube in their office. That would be funny.
During my BBC training in 1974, we visited the transmitter site at Daventry that transmits (amongst other things) the 1500 m (200 kHz) signal for BBC Radio 4. The final exciter valve (or vacuum tube if you prefer) was around two metres high and lived in its own glass-fronted wooden case. I don't know what kit they use nowadays to transmit that signal, though it's entirely possible they may still use it.
From Wikipedia:
In 2011 as part of the BBC cuts it was announced that there would be no re-investment in longwave which will mean an eventual end to BBC Radio 4 on longwave. It was later announced that the transmitter relies on a pair of metre-high glass valves that last between one and ten years. There were less than ten remaining in the world, and it is not feasible to manufacture new ones.