The station first signed on the air by Signal Hill Telecasting Corporation on August 10, 1953 as WTVI, broadcasting on UHF channel 54. It was originally licensed to Belleville, Illinois (across the Mississippi River from St. Louis) and was the second television station in the St. Louis market after KSDK on February 8, 1947. The station's first broadcast was a baseball game between the St. Louis Browns and Cincinnati Reds, announced by Buddy Blattner, Bill Durney and Milo Hamilton. It operated as a primary CBS affiliate, and held secondary affiliations with ABC and DuMont. DuMont affiliation was agreed to in February 1953 to replace KSD-TV. The station was project to sign on May 15, 1953. The station originally operated from studios located in Alton, Illinois. The CBS affiliation moved to KWK-TV (channel 4, now KMOV) when it debuted on July 8, 1954; more or less by default, WTVI became a primary ABC affiliate.