On November 16, 1955, the Federal Communications Commission awarded a construction permit to John L. "Jack" Breece for a new radio station to broadcast with 250 watts on 1400 kHz in Casper, initially called KTOO.
[14] KATI maintained a Top 40 format into the 1980s; it also had other program features, including local news and coverage of high school sports, and it was generally an audience leader in Casper's radio ratings.
[9] As a result, Mountain West converted KATI and KAWY to a simulcast, KATI-AM-FM, and restored the contemporary hit radio format.
[9] That lasted less than a year; when KATI lured away Terry Gross, a former announcer who had been fired from KTWO, it adopted the Music of Your Life syndicated oldies format in September.
[20][21] That format, in turn, lasted less than a year before management switched KATI to a simulcast of the FM station, KGRQ, and its album-oriented rock programming in August 1986.
November 21, 1987, became "the day the music died" in Casper when, at 11:52 p.m., KATI and KGRQ played a short announcement informing listeners of the stations' demise and one last song, "American Pie", before going silent.
[33] However, the UW rejected all three bids as too low—and because of the objection of Rosenthal to the sale of his gift to one of his competitors[30]—and announced it would make a go of raising funds to use KATI as a repeater of its public radio station, KUWR, which had only a 10-watt FM translator to serve the Casper area.
[34] Those efforts would not amount to anything; citing the improvement of the FM signal of Wyoming Public Radio in the Casper area, the university announced that it would let the license expire in March 1993.
[30] Rosenthal was disappointed by the university's decision not to use the station for the purpose he had intended upon donating it, to improve KUWR's signal to Casper.