Howard Hesseman, 81, who played the radio disc jockey Dr. Johnny Fever on the sitcom “WKRP in Cincinnati” and the actor-turned-history teacher Charlie Moore on “Head of the Class,” died Jan. 29 in Los Angeles due to complications from colon surgery, his manager Robbie Kass said Sunday. Hesseman, who had himself been a radio DJ in the 1960s, earned two Emmy nominations for “WKRP in Cincinnati,” which ran for four seasons from 1978- 1982.