![A homemade Audion radio receiver constructed by an amateur radio hobbyist 1914. The Audion (triode), the first amplifying vacuum tube, was invented by Lee De Forest in 1907 but was not widely A homemade Audion radio receiver constructed by an amateur radio hobbyist 1914. The Audion (triode), the first amplifying vacuum tube, was invented by Lee De Forest in 1907 but was not widely](https://c8.alamy.com/comp/2DYX1KH/a-homemade-audion-radio-receiver-constructed-by-an-amateur-radio-hobbyist-1914-the-audion-triode-the-first-amplifying-vacuum-tube-was-invented-by-lee-de-forest-in-1907-but-was-not-widely-used-until-its-amplifying-ability-was-recognized-around-1913-so-this-is-one-of-the-earliest-vacuum-tube-radios-2DYX1KH.jpg)
A homemade Audion radio receiver constructed by an amateur radio hobbyist 1914. The Audion (triode), the first amplifying vacuum tube, was invented by Lee De Forest in 1907 but was not widely
![Edwin Howard Armstrong (December 18, 1890 – January 31, 1954) was an American electrical engineer and inventor. He has been called 'the most prolific and influential inventor in radio history'. He invented Edwin Howard Armstrong (December 18, 1890 – January 31, 1954) was an American electrical engineer and inventor. He has been called 'the most prolific and influential inventor in radio history'. He invented](https://c8.alamy.com/comp/2B02PKK/edwin-howard-armstrong-december-18-1890-january-31-1954-was-an-american-electrical-engineer-and-inventor-he-has-been-called-the-most-prolific-and-influential-inventor-in-radio-history-he-invented-the-regenerative-circuit-while-he-was-an-undergraduate-and-patented-it-in-1914-followed-by-the-super-regenerative-circuit-in-1922-and-the-superheterodyne-receiver-in-1918-armstrong-was-also-the-inventor-of-modern-frequency-modulation-fm-radio-transmission-armstrong-was-born-in-new-york-city-new-york-in-1890-he-studied-at-columbia-university-he-later-became-a-professor-at-columbia-2B02PKK.jpg)
Edwin Howard Armstrong (December 18, 1890 – January 31, 1954) was an American electrical engineer and inventor. He has been called 'the most prolific and influential inventor in radio history'. He invented
![Guest post by Keith Thrower: Technical factors affecting CW radio communication in WW1, part 2 - Innovating in Combat Guest post by Keith Thrower: Technical factors affecting CW radio communication in WW1, part 2 - Innovating in Combat](http://blogs.mhs.ox.ac.uk/innovatingincombat/files/2014/06/Marconi-Short-distace-radio.jpg)
Guest post by Keith Thrower: Technical factors affecting CW radio communication in WW1, part 2 - Innovating in Combat
![A Centennial Celebration of Marconi & RCA Wireless Radio in West Marin, 1914-2014 - Point Reyes National Seashore (U.S. National Park Service) A Centennial Celebration of Marconi & RCA Wireless Radio in West Marin, 1914-2014 - Point Reyes National Seashore (U.S. National Park Service)](https://www.nps.gov/pore/planyourvisit/images/pic_marconi100_marshall_rca_morse_operators_1923_285x226.jpg?maxwidth=650&autorotate=false)