Radio History

Orgins And Development

Feb 17, 1820

Hans Christian Ørsted discovers the relationship between electricity and magnetism in a very simple experiment. He demonstrates that a wire carrying a current was able to deflect a magnetized compass needle.

Michael Faraday

Mar 16, 1831

1831: Michael Faraday begins a series of experiments in which he discovers electromagnetic induction. The relation was mathematically modeled by Faraday's law, which subsequently becomes one of the four Maxwell equations.

Edwin Huston

Apr 20, 1871

Edwin Houston, while setting up a large sparking Ruhmkorff coil to be used in a demonstration, notices he can draw sparks from metal objects throughout the room. He attributes this to induction

Electromagnetic field

Sep 17, 1873

James Clerk Maxwell, based on the work of previous scientists, theoretically predicts the existence electromagnetic waves in his paper to the Royal Society A Dynamical Theory of the Electromagnetic Field.

Acoustic Telegraph

Apr 19, 1875

While experimenting with an acoustic telegraph, Thomas Edison notices an electromagnet producing unusual sparks. He finds this strange sparking could be conducted 25 miles along telegraph wires and be detected a few feet from the wire.

Spark Detector

Dec 28, 1875

December 1875: Edwin Houston, with the help of Elihu Thomson, conducts an improved version Edison's experiment at Central High School in Philadelphia, Pennsylvania using a Ruhmkorff coil and a spark detector. Thompson notices he can draw sparks from metal objects throughout the building and looks on the phenomenon as a possible new form of communication

Telephone Microphone

Mar 16, 1878

David E. Hughes notices that sparks generated by a induction balance causes noise in an improved telephone microphone he was developing. He rigs up a portable version of his receiver and, caring it down a street, finds the sparking can be detected at some distance.

Brass Plates

Mar 5, 1884

1884: Temistocle Calzecchi-Onesti at Fermo in Italy discovers that metal filings between two brass plates clump together in reaction to electric sparks occurring at a distance.

Transmitter

Dec 24, 1906

24 December 1906: Reginald Fessenden used an Alexanderson alternator and rotary spark-gap transmitter to make the first radio audio broadcast, from Brant Rock, Massachusetts.

Wireless

Feb 17, 1909

1909: Marconi and Karl Ferdinand Braun were awarded the Nobel Prize in Physics for "contributions to the development of wireless telegraphy".

Ship Act

Jan 19, 1910

1910: The Wireless Ship Act was passed by the United States Congress, requiring all ships of the United States traveling over two-hundred miles off the coast and carrying over fifty passengers to be equipped with wireless radio equipment with a range of one-hundred miles.

Wireless Communication

May 16, 1913

1913: Marconi initiated duplex transatlantic wireless communication between North America and Europe for the first time, using receiver stations in Letterfrack Ireland, and Louisbourg, Nova Scotia.

KQW

Feb 17, 1921

officially granted experimental license as KQW, become commercial

Radio Station

Feb 17, 1921

Radio Journal de la Tour Eiffel

Radio Journal

Feb 17, 1923

Regular Czech service - Radiojournal