Station bumper stickers proclaimed "K-TUF/KNIX, We Stamped Out 3-Letter Radio." The bumper sticker referred to KOY AM 550, the leading radio station in Phoenix at the time, and the only one with a three-letter call sign. In 1976, the AM call letters switched to KNIX, while the FM station added the -FM suffix, creating KNIX-AM-FM. The AM station began programming classic country music, becoming the flagship station for a network called "Real Country." Meanwhile, KNIX-FM concentrated on contemporary and recent country hits. AM 1580 KNIX ended its association with the Real Country Network in 1985 and the AM-FM simulcast was restored.
