1912: Prof. F.W. Springer begins experimenting with radio transmissions.

1915: U of M football games are first aired -- in Morse code.

1920: "Radiotelephone" broadcasts begin, including farm reports, weather forecasts and concerts.

1922: University receives the state's first radio broadcasting license. Educational material is the main focus through the 1940s.

1945: The station's call letters are changed from WLB to KUOM.

1946: A polio epidemic that closed schools leads to the creation of the Minnesota School of the Air, aimed at homebound children.

1948: A second station, student-run WMMR, is founded. It focuses on music, sports and news.

1960s: Garrison Keillor gets his start, broadcasting classical music on WMMR, then going to work at KUOM.

1970: WMMR becomes an important source of news on antiwar protests and student strikes.

1980s: WMMR becomes first a Top 40 station, then college/alternative. KUOM, meanwhile, taps faculty for call-in shows on current events, the arts and practical topics such as gardening.

1993: The two stations merge and Radio K is born. A website, RadioK.org, follows a year later.

2009: Long limited to daytime hours and the AM dial, the station goes live 24 hours a day via FM.