Here's another clip from Weekday Heroes, that 1984 special on the kids' show hosts of Los Angeles. This one is about Sheriff John. (I linked to a clip about Chucko the Clown in this post. Again, that's Tony Dow hosting.)
John Rovick was another one of those staff announcers and TV personalities in local television who was told one day to come up with a costume and a persona and to go out and host cartoons. Almost everyone who was on staff at a local station in the fifties got such orders and some of them became so popular that they did it for years and became part of countless childhoods. Sheriff John was on KTTV from '52 (the year I was born) until 1970. He then continued to work as a staff announcer at the station for at least another ten years before retiring to Idaho where, we hear, he's still alive and well.