Broadcasting of sports events
NBC broadcast the first televised National Football League (NFL) game when they carried the 22 October 1939 game between the Philadelphia Eagles and the Brooklyn Dodgers. The same year, the first nationwide radio broadcast of an NFL championship game was carried on the Mutual Broadcasting System. While the NFL had weak television deals that ranked behind college football and even the Canadian Football League in the 1950s, the broadcast rights of the NFL would go on to become an important property following the 1958 NFL Championship and the later establishment of the American Football League in 1960. "Monday Night Football", "NFL on Fox", and "NBC Sunday Night Football" have changed the landscape of American football broadcasts, including the scheduling of the Super Bowl, transforming it from an afternoon broadcast into a primetime spectacle. The price for the NFL's broadcast rights has increased steadily over the past several decades, in part because of bidding wars between the numerous networks and the fear of losing stature due to the loss of NFL programming; as of the most recent contract the league nets annual fees of over $6 billion, or half of the league's overall revenue, from television rights alone. Four of the five major sports television units in the United States, and the four companies that control all of the major broadcast networks, currently own some NFL rights.
NFL on CBS
From 1956 to 1959, the Baltimore Colts, Pittsburgh Steelers and Philadelphia Eagles only had their away games telecast on CBS. When these three played at home, there was no need for the usage of split audio. Instead, the away team's telecasts were produced in a simple singular audio-video feed. In 1959, 1960 and 1961, NBC had the rights to televise Colts and Steelers home games. While the game broadcasts were blacked out (as per NFL policy) in those cities, they were available to other NBC-affiliated stations.