Howard Hesseman, enshrined in pop culture history for his role as radio disc jockey Dr. Johnny Fever on CBS sitcom “WKRP in Cincinnati,” has died at 81.

The actor scored two Emmy nominations as best supporting actor in a comedy for his role on the show, which ran from 1978 to 1982. He also played architect Sam Royer, Ann Romano’s second husband and Barbara’s father-in-law, on “One Day at a Time,” and went on to star in “Head of the Class” as history and social studies teacher Charlie Moore in the ’80s.

His manager Robbie Kass confirmed Sunday to USA TODAY that Hesseman died on Saturday in Los Angeles from complications of colon surgery, calling him a “groundbreaking talent” and lifelong friend, “whose kindness and generosity was equaled by his influence and admiration to generations of actors and improvisational comedy throughout the world.”

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DJ Dr. Johnny Fever (Howard Hesseman, left) chats up a caller while program director Andy Travis (Gary Sandy) listens in on "WKRP in Cincinnati."

DJ Dr. Johnny Fever (Howard Hesseman, left) chats up a caller while program director Andy Travis (Gary Sandy) listens in on “WKRP in Cincinnati.”

Hesseman, who in real life worked as a DJ in the 1960s and frequently ad-libbed Fever’s on-air banter, became a counterculture icon for the role at a time when few hippie characters made it onto network television.

As Fever, he spun now-classic rock songs such as Boston’s “Don’t Look Back,” Toto’s “Hold the Line” and Blondie’s “Heart of Glass,” many of which owed a debt to “WKRP” for growing their audience.

“I think maybe Johnny smokes a little marijuana, drinks beer and wine, and maybe a little hard liquor,” Hesseman told The New York Times in 1979 as he readied for one of three “Saturday Night Live” hosting gigs. “And on one of those hard mornings at the station, he might take what for many years was referred to as a diet pill. But he is a moderate user of soft drugs, specifically marijuana.”

Howard Hesseman, seen here in 2013, has died at 81.

Howard Hesseman, seen here in 2013, has died at 81.

Hesseman started out as a member of the improv group The Committee and at the time he moonlighted on Saturdays as a DJ for San Francisco rock ‘n’ roll station KMPX.

He launched his acting career with a guest role on “The Andy Griffith Show” in 1968 and went on to become a go-to character actor for both TV and film, with his many memorable turns including appearances on “The Bob Newhart Show” and “Mary Hartman, Mary Hartman” and film roles in “Shampoo,” “The Other Side of Midnight” and “This Is Spinal Tap.” He was also seen on the syndicated reboot “The New WKRP in Cincinnati” from 1991 to 1993.

“Laverne & Shirley” actor and comedian Michael McKean, who starred with Hesseman in “Spinal Tap,” hailed the actor’s bona fides on Twitter. “Impossible to overstate Howard Hesseman’s influence on his and subsequent generations of improvisors,” he wrote. He recalled first seeing Hesseman in 1971 with The Committee. “I saw that he was the real deal.”

Original “Saturday Night Live” cast member Laraine Newman mourned him as a close friend. “RIP Howard Hessman. What great times we had,” she tweeted. “Great laughs and fun going to see Etta James in Manhattan Beach and Joe Tex at The Parisian Room. Staying at your beautiful house in Ramatuellle. Oh god this hurts.”

Born in Lebanon, Oregon, Hesseman wasn’t so disconnected from some of the characters he played. In 1983, he told People that he had conducted “pharmaceutical experiments in recreational chemistry.” He was once jailed in San Francisco for selling marijuana in the ’60s.

His “WKRP in Cincinnati” co-star Frank Bonner, who played polyester plaid-clad salesman Herb Tarlek, died last summer at age 79 from complications of Lewy body dementia.

“WKRP” took place at a struggling Ohio radio station trying to reinvent itself with a rock format. The cast included Hesseman, Bonner, Gary Sandy, Tim Reid, Gordon Jump, Loni Anderson, Richard Sanders and Jan Smithers.

Hesseman is survived by his wife, Caroline Ducrocq, an actress and acting coach.

Contributing: Kim Willis, USA TODAY, and Jake Coyle, The Associated Press

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This article originally appeared on USA TODAY: Howard Hesseman dies: ‘WKRP in Cincinnati’s Dr. Johnny Fever was 81