About WOAI News 4 San AntonioThe station first signed on the air on December 11, 1949 as WOAI-TV. It was the first television station in the San Antonio market, owned by Southland Industries along with AM 1200 WOAI. WOAI-TV and WOAI radio are among the few broadcast stations located west of the Mississippi River that have a call sign beginning with "W." In the early days of broadcasting, most Central Time Zone states were in the "W" territory. In 1923, the dividing line was changed to the Mississippi River. Since WOAI Radio was already on the air, it kept its W call letters and when it put a TV station on the air, it shared that call sign.
WOAI-TV has been an NBC affiliate since its sign-on, due to WOAI (AM)'s longtime affiliation with the NBC Red Network. But at first, it also carried programming from the three other major networks of the time: CBS, ABC and DuMont. WOAI lost the CBS and DuMont affiliations to KEYL (channel 5, now KENS) when that station signed on in February 1950. The two stations continued to share ABC programming until KONO-TV (channel 12, now KSAT-TV) signed on in January 1957.