The station first signed on the air on December 21, 1952, as WSBA-TV, originally operating as an ABC affiliate. It was owned by the Susquehanna Radio Corporation, a subsidiary of the Susquehanna Pfaltzgraff conglomerate, along with radio station WSBA (910 AM). It was one of the first commercially licensed UHF television stations in the United States, signing on the air just over three months after KPTV in Portland, Oregon which originally broadcast on channel 27 when it signed on in 1952, before moving to VHF channel 12 five years later. This makes WPMT the second-oldest continuously broadcasting UHF station in the country, only behind WSBT-TV in South Bend, Indiana (although WSBT moved from its original channel 34 to channel 22 in the late 1950s, making WPMT the oldest UHF station that broadcasts continuously on the same virtual channel number to this day).