The down-on-his-luck singer sat on the steps of Nashville's famed Grand Ole Opry, bemoaning the job he'd just lost at a radio station, when out walked country legend Hank Williams.

The celebrated but troubled singer and songwriter, who had just been fired from the Louisiana Hayride radio show in 1949, suggested they apply for each other's former jobs.

"Just go down there and give them all you've got," Williams told cowboy balladeer Slim Whitman, who died Wednesday of heart failure outside Jacksonville, Fla. He was 90.

His death was announced by his son-in-law, Roy Beagle.

Williams' advice worked out beautifully for Whitman, the yodeling singer who parlayed his string of 1950s country hits into even greater commercial success and broad-based recognition three decades later through a savvy telemarketing campaign for his recordings.

Those ads turned Whitman into both a beloved and much-lampooned symbol of an earlier age of western music marked by his signature leap-frogging vocals.

Although Whitman never scored a No. 1 hit in the U.S., his 1952 recording of "Indian Love Call" reached No. 2 on Billboard's country singles chart, as did "Secret Love" two years later, a song featured in the film "Calamity Jane" starring Doris Day.

Ottis Dewey Whitman was born Jan. 20,1923, in Tampa, Fla. By age 12 he was imitating some of his favorite singers, among them Jimmie Rodgers, known as "The Father of Country Music," who helped bring the Austrian technique of falsetto vocal leaps into country music in the early 20th century.

As a boy "I would sing like him at parties and even do the yodels," Whitman told the Florida Times-Union in 2000. He also later modeled himself on country singer Eddy Arnold before developing a style of his own that endeared him to audiences in the U.S. and, especially, in England, where he found greater success on many levels than he'd registered in his native country.

His 1954 single "Rose Marie" spent 11 weeks at No. 1 in the United Kingdom, a record that stood until Bryan Adams surpassed it in 1991 with "Everything I Do (I Do It For You)."

During World War II Whitman served in the Navy on a ship stationed in the South Pacific. After his discharge, he landed a contract in 1948 with RCA Records on the recommendation of Col. Tom Parker, who had been guiding Eddy Arnold's career before handling Elvis Presley's business affairs. Whitman joined the Louisiana Hayride in 1950 after the encounter with Williams.

Whitman's pencil-thin black mustache, sharp eyebrows, squinting smile and angular features gave him the look of a bad guy out of a 1940s B Western, but Whitman — nicknamed "The Smilin' Star Duster" — always prized his unsullied reputation as a musician and public figure.

"When other guys were out drinking, I would call my wife every night when I was on the road," he told the Florida Times-Union.

Millions remember him from the ubiquitous TV ads that began in 1980, when New York-based Suffolk Marketing offered a collection of his hits through a direct-marketing campaign. Company officials said it sold more than 2 million copies, but it only reached No. 175 in Billboard at the time. The ads were subsequently lampooned by comedians, notably by Joe Flaherty on SCTV.

Director Tim Burton chose Whitman's voice as the saving grace of humanity in his 1996 film "Mars Attacks!" in which marauding aliens were ultimately destroyed by his stratospheric yodeling.

Whitman said that he was reluctant to commit to the TV ads, and that he had been talked into it by his son, Byron, who joined his father's stage show in later years.

"My son has put spunk in the old man," Whitman told the Associated Press in 1991. "He has the same type high voice. He can match my yodels."

Whitman did not expect the television marketing to "catch on like it did," he told the Washington Post in 1981."But when I'd go to the malls shopping, more and more of the little fellows were pointing — 'Hey, Mommy, Mommy, I just saw him on television.' That's the way I found out something was happening."

In 2002 he stopped touring to care for his wife, Jerry, who was on dialysis. The couple had been married for 67 years when she died in 2009. In addition to their son, they had a daughter, Sharron.

Whitman wanted to be remembered "as a nice guy — with a white hat," he had said in the AP interview. "I don't think you've ever heard anything bad about me, and I'd like to keep it that way.

randy.lewis@latimes.com