The current format on the station was derived in part from another Boulder station, KADE 1190 AM (now KVCU). KADE was a solar-powered daytimer station, which signed on and off the air in conjunction with the rising and setting of the sun. KADE was purchased in 1975 by Bob Greenlee. Two years later, Greenlee also purchased KRNW, which then became KBCO-FM. The original studio was located in an office complex at 1900 Folsom Street in Boulder. The station's original transmitter was located on a tower atop Lee Hill. Bob Greenlee worked with consulting engineers and petitioned the Federal Communications Commission to boost KBCO's power.