One of the first radio stations to undertake broadcasting in the United States was KDKA in Pittsburgh, which announced the results of the 1920 presidential elections. Two years later the number of licensed broadcasting stations had increased to 500, but only 2 million Americans owned radio sets. By 1939 there were 1,465 stations in the United States and four networks.At the start of the 1940s, the number of households owning a radio had more than doubled. NBC, with its innovative programs and informative broadcasts remained among the most popular radio stations in the 40s and 50s. This video deals in part with the story of the beginnings and achievements of NBC. It also provides a glimpse of Coney Island in its heydays and a review of the Columbia University student's strike in 1969.