He grew up in Poughkeepsie, New York, nicknamed "Sarge," after his father's rank in the United States Army during World War II. A radio enthusiast from an early age (with an amateur radio station K2KOQ in a corner of the basement)' in 1963, he became a DJ ("Large Sarge") on WHVW in nearby Hyde Park. He went on to stations in WBAZ in Kingston, WENE in Binghamton, New York and WMID in Atlantic City, NJ before landing in New York City,
In 1968 Donovan landed overnights on WOR-FM, where he was named "Johnny Donovan" by Bill Drake.
He was doing middays 4 years later at WOR-FM, when he moved from the FM dial to the AM dial on July 9, 1972, and to his home for the last 43 years, WABC.
"During the music days at WABC, Donovan was the glue that held the place together as the main fill in person, as well as holding down his own regular weekend shifts", longtime WABC engineer Frank D'Elia stated in an eMail..
For the last several years before talk, Johnny held down a Monday through Friday mid-day shift.
When WABC switched in May 1982 from Musicradio to Talkradio, Johnny stayed on as a Staff Announcer, but that position quickly morphed into the position Production Director as Johnny became one of the pre-eminent voice and production people in the radio business.
For the last 35 years, Donovan's voice has been involved in thousands of commercials and spec spots, show opens (no one else can say that they’ve been the voice of the Rush Limbaugh Show since it debuted in 1988), WABC station production pieces, and special programming (he produced and was the host for 10 years of the yearly WABC Rewound broadcast that looked back every Memorial Day weekend at the Musicradio days of WABC).