WLWT counts itself as the first television station outside the Eastern U.S. (other than network-owned stations) to become a primary NBC television affiliate, but originally carried programming from all the major television networks of the time: NBC, ABC, CBS and DuMont. WLWT later affiliated exclusively with NBC in 1949, after WKRC-TV (originally on channel 11, now on channel 12) and WCPO-TV (originally on channel 7, now on channel 9) signed on during that year. Following the release of the FCC's "Sixth Report and Order" in 1952, all of Cincinnati's VHF stations changed channel positions. WLWT was reassigned to channel 5, as the previous channel 4 allocation was shifted north to Columbus and given to sister station WLWC (now WCMH-TV), which began operations in April 1949.