NBC 50 Years of Radio

the NBC Red Network from 1927 to 1942)[a] was an American commercial radio network which was in continuous operation from 1926 through 1999. Along with the NBC Blue Network, it was one of the first two nationwide networks established in the United States. Its major competitors were the Columbia Broadcasting System (CBS), founded in 1927, and the Mutual Broadcasting System, founded in 1934.

 In 1942, NBC was required to divest one of its national networks, so it sold NBC Blue, which was soon renamed the American Broadcasting Company (ABC). After this separation, the Red Network continued as the NBC Radio Network.For the first 61 years of its existence, this network was owned by the Radio Corporation of America (RCA) with New York City radio station WEAF (renamed WNBC in 1946, WRCA in 1954 and again as WNBC in 1960) as its flagship station.

Following the emergence of television as the dominant entertainment medium and much of NBC Radio's talent migrating both to CBS and NBC television, the network made multiple investments in programming in hopes of retaining relevance. These included the weekend program umbrella Monitor (1955–1975), the all-news focused NBC News and Information Service (1975–1977) and the talk radio service NBC Talknet, all of which encountered varying degrees of success and failure.