1892 to 1893

Nikola Tesla wirelessly transmitted electromagnetic energy. He made the first public demonstration of radio in St. Louis in 1893.

1896 to 1897

Guglielmo Marconi filed for patent protection of his radio apparatus. He established the Wireless Telegraph and Signal Company in 1897.

1901

First transAtlantic signal sent-by Marconi from Ireland to Canada.

1902

Amateur (today known as “ham”) radio introduced to the U.S. via a Scientific American article on “How to Construct an Efficient Wireless Telegraphy Apparatus at Small Cost.”

1906

Reginald Fessenden is the 1st to transmit a program of speech and music.

1910 

First radio transmission from an airplane.

1917

All U.S. radio stations not needed by the government are closed as WWI begins.

1922

The first on-air advertisement was carried by a New York station.

1926

The first permanent national network, NBC, was formed. CBS followed a year later.

1927 

The Federal Radio Commission established to bring order to chaotic airwaves.

1933

FDR broadcast the first of his 30 “fireside chats”

1938

CBS Radio broadcasts H.G. Wells' classic The War of the Worlds. Although most listeners understood that the program was a radio drama, the next day's headlines reported that thousands of others -- perhaps a million or more -- plunged into panic, convinced that America was under a deadly Martian attack.

1947

Cellular radio telephony, with call handoff and frequency reuse, was conceived at Bell Laboratories

1954

Texas Instruments produces the first commercial transistor radio, launching the portable electronic age.

2001

XM Radio

Sources:

Federal Communications Commission. (2004). A short history of radio with an inside focus on mobile radio. Retrieved form https://transition.fcc.gov/omd/history/radio/documents/short_history.pdf

Latson, J. (2015, March 12).  How FDR’s radio voice solved a banking crisis. Time. Retrieved from http://time.com/3731744/fdr-fireside-chat-banking/

LEFT, Inc. (2008). The history of satellite radio. SatelliteRadioUSA. Retrieved from http://satelliteradiousa.com/satellite_radio_privacy_policy.html

National Capital Radio & Television Museum. (2017). Exhibitions. Retrieved from http://ncrtv.org/exhibitions/

PBS. (n.d.). Introduction: War of the Worlds.  Retrieved from http://www.pbs.org/wgbh/americanexperience/features/introduction/worlds/

Stromberg, J. (2011, October 18). The transistor radio launches the portable electronic age. Smithsonian. Retrieved from http://www.smithsonianmag.com/smithsonian-institution/the-transistor-radio-launches-the-portable-electronic-age-110761753/#SW4UwzUoSs9XCf0P.99