Bob Jenkins never forgot the Winnebago ad. It ran during a football game while he was at his sister’s house for Thanksgiving.

“I remember sitting there thinking, ‘50 million people are hearing my music right now,’ ” Jenkins later recalled in an interview.

That was one of his first advertising music tracks. But Jenkins’ tunes were soon blasting from television sets across the country, from doo-wop extolling breakfast sandwiches to rock ’n’ roll selling hair dryers.

Jenkins, a prominent big-band trombonist who became an award-winning composer of commercial music, died Aug. 8 of heart problems. He was 80.

The Minneapolis native and Roosevelt High School grad first made his mark as a freelance musician, playing around the world with big-band titans like Woody Herman, the Glenn Miller Orchestra and the Tommy Dorsey Orchestra. He recorded tracks in New York studios, including elevator music he would hear in elevators years later.

At 23, he was playing lead trombone in a recording studio alongside Urbie Green and Bill Watrous — two heavyweights of the instrument.

“He said, ‘This is about as good as it gets for a trombone player,’ ” his friend Kent Saunders said, adding that Jenkins decided it was time to try something new.

So he moved to Omaha — and later Minneapolis and Chicago — and began writing music. Some compositions were scores for “industrials,” films that corporations produced to energize their employees at annual conferences. But he became best known for commercials.

“One of the things he liked about the commercial business is it was popular and it had other elements,” Saunders said. “One day you’d do a swinging thing, and the next day you might do a light-rock thing.”

One of the most prominent spots he composed was a 1970s campaign for Metz Baking Co.’s Old Home Bread, chronicling a bread truck driver’s interactions with a waitress on the road. Jenkins wrote the country score and Bill Fries sang under the name C.W. McCall — in a deadpan, narrative style he later made famous in the song “Convoy.”

The ads caused a sensation. The Wall Street Journal wrote that people called TV stations asking them to replay the ads and that C.W. and Mavis, the waitress, had “become something of folk heroes in Metz’s [Midwest] territory.” Industry professionals named it the best TV campaign of the year.

“Now the music track was just plain happiness, recorded that mother up in Minneapolis,” Fries sang later in a musical history of the campaign. “A fellow named Jenkins wrote the guitar chords for a dollar a chord … Man alive I’m telling you, the fiddles and the guitars really flew.”

In addition to TV jingles, Jenkins also wrote film scores.

In the early 2000s, he started teaching music composition at the Institute of Production and Recording in downtown Minneapolis, where he worked until recently. Colleague Kevin Bowe said Jenkins made a point of learning new music software.

“He was like an old young guy,” Bowe said. “He was the hippest guy in the room.”

Jenkins was also an active member of Alcoholics Anonymous, at the Alano Society in south Minneapolis, and led workshops on the recovery process. Before his death, Jenkins received a token for 50 years of sobriety.

In a 2008 talk, Jenkins recalled how his alcoholism flared during his time as a big band musician. “If you’re a musician, you not only drink at work, you’re kind of expected to drink at work,” Jenkins said.

But when telling his story, he was often mum about his prominent past. “He had a really big life, but he didn’t really share a lot about it,” said friend Rick Bowman.

Jenkins is survived by a son, Richard of Minneapolis, and a sister, Susie of Brainerd. Services have been held.