1865 John Clerk Maxwell Postulates Electric Waves Travel at Light Speed, 1884 Heinrich Hertz Demonstrates It

 

1890 Eduord Branly Develops Coherer Radio Receiver

 

1891 Tesla Lectures and Demonstrates Wireless System, 1894 Patents Wireless Transmission System

 

December 1901 Marconi Receives Wireless Transmission in Newfoundland Sent from Ireland

 

1912 Sarnoff at Telegraph as Titanic Sinks After Being Rejected by Marconi, Later Takes over Marconi

1895 Tesla NY Lab Fire, 1900 Sells Patent Rights to Morgan, Experiments in Colorado, 1912-17 Wardenclyffe

Artificial Lightning for High Power Electric Transmission, Wireless Boat, Phosphorescence, X-Ray Experiments

 

1914 Marconi Builds Marin Pacific Transmission Center Before Leaving America for Italy in World War I

 

1899 Ambrose Fleming Vacuum Tube, 1904 Vacuum Valve Expanded in 1906 to Audion with Third Plate

 

1906 Reginald Fessenden Pioneers Radio Broadcasting with Superheterodyne Amplification, Christmas Music

 

1914 Edwin Armstrong Invents Regenerative Circuit Using Audion, Starts Long Patent Battle with de Forest

1918 Armstrong Develops Superheterodyne as Path to Commercial Radio Broadcasting and Reception