By Joel SelvinFew disc jockeys have ever affected the actual development of radio, but Tom Donahue was no mere disc jockey. In a field where a person with just one good idea can look like an intellectual giant, Tom Donahue, who died Monday of a heart attack at age 46, was a true visionary. The whole country noticed San Francisco radio when Donahue created what quickly came to be called "underground radio" on KMPX-FM here in 1967, opening the FM airwaves to rock for the first time. His mark is stamped throught the history of rock music in San Francisco. He spent five years as one of the citys most popular AM radio rock broadcasters on KYA, produced giant rock concerts here before Bill Graham even moved to San Francisco, and owned the record company that spawned San Franciscos first home-grown hit rock records. Donahue became general manager of KSAN-FM in October 1972, a position he held until his death. He came to KSAN in May, 1968, with almost his entire KMPX staff, following a bitter strike at the original station. With Donahue at the helm, KSAN has remained virtually unchallenged as the top progressive rock station in town. At the zenith of KMPXs influence, Donahue broadcast nightly both in San Francisco and Los Angeles on KMPXs Pasadena sister station, KPPC-FM, using tape recorded shows to overcome the geographic problem. Later, he served as programming consultant for KMET-FM in Los Angeles, which memorialized Donahue there throughout the day following his death. At KSAN, commercial announcements were canceled for 24 hours; a KSAN memorial program is scheduled for 6 oclock to midnight tonight, Donahues regular time slot. Tom "Big Daddy" Donahue came to San Francisco in 1961 from Philadelphia. With his partner, the late Bob Mitchell, he presented a series of early rock concerts at the Cow Palace, including shows by the Rolling Stones and the Beatles. The pair also produced the 1966 Candlestick Park performance by the Beatles; the final public performance by the quartet, and opened the countrys first psychedelic nightclub, Mothers on Broadway, where the Lovin Spoonful played for peanuts. He ran Autumn Records, which recorded San Franciscos first hit rock group, the Beau Brummels. "A whore told me about them," Donahue liked to recall, "and I always listen to whores." Bobby Freeman earned a million-seller on Autumn with "Cmon and Swim" in 1964. Rock star Sly Stone worked as a producer for Autumn, and the Jefferson Airplanes Grace Slick made her first records (with The Great Society) for Donahue. "The disc jockeys have become robots," he wrote for Rolling Stone in 1967, lambasting AM radio in an article titled "AM Radio Is Dead and Its Rotting Corpse Is Stinking Up the Airwaves." They are "performing their inanities at the direction of programmers who have succeeded in totally squeezing the human element out of their sound, and reducing it to a series of blips and bleeps and happy, oh yes, always happy, sounding cretins who are poured from bottles every three hours. They have succeeded in making everyone on the station staff sound the same -- asinine. This is the much coveted station sound," he said. His voice rolled from his throat like thick oil pouring from the can. His musical selections never betrayed his age and experience; he was always up-to-the-minute hip. His work earned him awards from Billboard, San Francisco State and the Bill Gavin Radio Conference, among others, over the years. "He always laughed and threw them away," his secretary, Vicki Cunningham, said. Donahue is survived by his wife, Raechel, who has become one of KSANs most popular (and best) disc jockeys herself, and five children: Catherine (Buzzy), 25, Tom Jr., 23, Sean, 20, Deirdre, 16, and Jesse, 4.