The station's digital signal is multiplexed:
In addition to the main signal, WAGM operates three translators.
WAGM-TV signed on October 13, 1956 on VHF channel 8. It was a CBS-affiliate owned by Harold Glidden and the Aroostook Broadcasting Corporation along with WAGM radio (then at 1450 AM; later at 950 AM). The transmitter was behind the station's Brewer Road studios, providing a coverage area limited to the immediate area including Presque Isle and Caribou. In 1957, Glidden sold Aroostook Broadcasting to Community Broadcasting System, a company controlled by former Governor Horace Hildreth, who also owned WABI-AM-TV in Bangor.
Soon afterward, the station changed its primary affiliation to NBC, matching WABI-TV; however, WAGM-TV maintained secondary affiliations with CBS and ABC. It returned to being a primary CBS affiliate, again following WABI's lead, in 1959. However, in practice, as an affiliate of all the big three networks, WAGM cherry-picked the most popular programs for its prime time lineup.
Community Broadcasting Service merged with Journal Publications in 1971 to form Diversified Communications. WAGM radio was sold in 1981 and renamed WKZX; it went silent in the late-1980s. The radio station's building still exists today but appears abandoned, while the three transmitter towers nearby were dismantled sometime in the early-1990s. In 1984, Diversified Communications sold WAGM-TV to NEP Communications, then-owner of WNEP-TV in Scranton, Pennsylvania. NEP sold WNEP to The New York Times Company a year later, but retained WAGM under the licensee name NEPSK, Inc. At one point co-owned by Tom Shelburne, Peter Kozloski, and Norman Johnston, Kozloski assumed full ownership of the station in 1991, retaining the NEPSK name.