Adrian Cronauer, the disc jockey whose story provided the rough outline for the character played by Robin Williams in the 1987 movie “Good Morning, Vietnam,” died Wednesday in Troutville, Virginia, He was 79.

His death was announced by Oakey’s funeral service. The notice did not give a cause.

Cronauer was in the Air Force in 1965 when he was sent to Saigon (now Ho Chi Minh City). His first job was as news director for Armed Forces Radio there, but when the morning host’s slot became vacant shortly after his arrival, he settled in behind the microphone. The show was called “Dawn Buster,” and he began it with the drawn-out greeting immortalized in the movie’s title.

He had actually developed the sign-on thousands of miles away, while stationed on the island of Crete, where he had also had a radio show.

“I said, ‘Good morning, Iraklion,’ because it was Iraklion Air Station,” an Air Force facility near the capital, he told CNN in 1995.

He initially wondered if the greeting might be too upbeat or bombastic to use in Vietnam.

“They’re young guys in this horrendous heat, slogging through rice paddies with mosquitoes the size of Mack trucks, picking leeches off themselves, shooting and fighting and killing and being killed,” he said.

“Do I want to do that?” he said in reference to using the opening line. “I said, ‘Yeah, I do, because if there’s a certain amount of irony there, and if they pick up on that, they’ll know what I’m really saying.’”

Years later, in 1979, with the Korean War sitcom “M.A.S.H.” and the radio-themed “WKRP in Cincinnati” both on the air, he tried selling a treatment of his experiences as a television series but found no takers. A few years after that he pitched a made-for-TV movie.

“This time, a friend’s agent in Hollywood got it into Robin’s hands,” Cronauer related in the 1995 interview, “and he said: ‘Oh, disc jockey; chance to do all my comic shtick. Let’s do it as a real movie.’”

But not one that used Cronauer’s version of events; what ended up in “Good Morning, Vietnam,” which was directed by Barry Levinson, was a largely fictionalized story from a screenplay by Mitch Markowitz.

Still, Williams said in a 1988 interview with Rolling Stone, key elements of the character he created came from Cronauer.

“He did play rock ‘n’ roll, he did do characters to introduce standard Army announcements, and ‘Goooood morning, Vietnam’ really was his signature line,” Williams said. “He says he learned whenever soldiers in the field heard his sign-on line, they’d shout back at their radios.” What they shouted is unprintable.

Cronauer, who in reality was not quite the wild man the film suggested — later in life he worked for Republican causes and became a lawyer — admitted to some unease when he first saw the screen portrayal. But he got over it.

“Finally I said: ‘Wait a minute. It was never intended to be a biography. It’s a piece of entertainment. Sit back, relax and enjoy it,’” he said. “And that’s what I did.”

Adrian Joseph Cronauer was born on Sept. 8, 1938, in Pittsburgh. As a youngster he played piano on a local children’s television show. He also listened to a lot of radio, particularly absorbing the style of Rege Cordic, a morning host in the Pittsburgh market.

In the 1950s he enrolled at the University of Pittsburgh. He and other students formed the Student Broadcasting Association, which began a campus radio station. He later transferred to American University in Washington, working at local radio stations in his spare time.

He joined the Air Force and was first assigned to work on training films before being sent to Crete. Then came his Vietnam stint.

He was there only in 1965 and 1966, but the DJs who succeeded him picked up his signature opening, and in later years many Vietnam veterans who served after he had left the country would meet him and, because of the movie, say they remembered listening to him.

He said that on the radio in Vietnam he was always conscious that his listeners were young soldiers who were strangers in a strange land.

“Along came the military and literally picked them up, took them halfway around the world and dropped them into a totally alien environment,” he told a luncheon in 1997. “Culture shock would set in with a vengeance. And it was our job — or as they like to say in the military, our mission — it was our mission to be an antidote to that culture shock by giving them something familiar to listen to. And what I tried to do is to make it sound as much as I could like a stateside radio station.”

After the war he worked at various stations as a news anchor and in other capacities, did voice-over work in New York and owned his own advertising agency. In the late 1980s, thanks to the money he had received from “Good Morning, Vietnam,” he was able to earn a law degree from the University of Pennsylvania.

Cronauer was active in veterans’ causes and from 2001 to 2009 was an adviser to the Defense Department’s Prisoner of War/Missing in Action Office. He was also on the board of the National D-Day Memorial and served two terms as a trustee of the Virginia War Memorial.

Cronauer, who lived in Troutville, was married to Jeane Steppe Cronauer, who died in 2016. His survivors include a stepson, Michael Muse, and four grandchildren.

A sought-after speaker once the movie came out, Cronauer would often note that Williams’ film rendition of his sign-on was actually somewhat underplayed.

“If you’re a morning DJ, it’s not a matter of if — it’s a matter of when: You are going to oversleep,” he told a 2008 gathering. “And when that happens you come tearing into the station at the very last moment, and you’re staggering around half asleep, half dressed.

“You don’t have any records pulled, you don’t know where your headphones are, you haven’t put in your contact lenses, you don’t have any tapes set up. It’s just chaos, and as you walk through the studio door, you hear the newsman saying: ‘That’s the latest from the Armed Forces Radio newsroom. Next news in one hour.’

“Now you’ve got to do something. So as you try and pull some records and find your headphones and get things all set up, you turn on the microphone and you say, ‘Gooood morning, Vietnam.’”

While pantomiming the pulling of records off shelves and the putting in of contact lenses, he drew out the “Goood” for a full 20 seconds.