Page "John Ambrose Fleming" Paragraph 13

: One century ago, in November 1904, John Ambrose Fleming FRS, Pender Professor at UCL, filed in Great Britain, for a device called the Thermionic Valve.

When inserted together with a galvanometer, into a tuned electrical circuit, it could be used as a very sensitive rectifying detector of high frequency wireless currents, known as radio waves.

It was a major step forward in the ‘ wireless revolution ’.