Yessiree, pardner, it's that Late Show music. Easy violins, overlaid with the clip-clop of horses' hooves. It says sagebrush. It connotes cowboy.

It also begins to lure the Monday afternoon shoppers wandering through the Mall at Manassas. A few dozen have gathered by the time the tall man in the yellow cowboy outfit flicks a switch.

Reverberating from the Peoples Drug to Montgomery Ward's and back again, the recorded voice is full of excited hype. "Ladies and gentlemen," it trumpets, "here he is! From Mineral Springs, Texas, that well-known western Entertainer, Cowboy Wimpy! Let's give him a warm welcome!"

The fact that they do is what keeps Wilbur J. Hall going. For 50 of his 65 years, all over the Washington area, he has donned one of his eight cowboy outfits, twirled his ropes and made the kiddies smile.

"I get to do what I like to do: show off," says Cowboy Wimpy. "I can't get enough of it."

It matters little that the Wimp is really from Arlington, Va. Mineral Springs? I never even heard of that damn place. It matters less that his hair is now almost snow white, or that he sometimes fluffs his rope tricks.

When Cowbow Wimpy is up there teaching a 4 year-old girl to spin a lariat and her mother is taking dead aim at the scene with an Instamatic, that old cowpoke magic is alive and well.

Cowboy Wimpy's magic first began to take shape in a less-than-magic setting the laundry room of the Hall home in Clarendon, in the mid 20s. There young Wilbur the second of three boys, would cadge a clothesline from his stepmother and practice the stunts he still uses today.

At 15 when vaudeville in Washington was not spelled with an X. Wimpy, as he was known even then, would speak downtown to watch the ropers from the traveling shows.

One trouper Dick Nash, "told me I was doing everything backwards, and he offered to show me the right way." Wimpy recalls The Young lad eagerly accepted. Then, having bought his first "good rope" for $5 from another ranchhand. Cowboy Wimpy hit the road with a group of fat ladies, snake charmers and untamed beasts from the Amazon.

For the better part of a year, young Wimpy and the troupe toured the East Coast. But the dream soon washed out in a sea of poverty and fond memories of home cooking.

I came home and Daddy said, "Listen, why don't you learn a trade?" "So Wilbur Hall became a lithographer. He spent 30 years with the Navy Department, returing four years ago. "I left the day I had 30 years, the very day." Hall remembers, "I made them check six times."

But he never let Wimpy ride off into the sunset. On nights and weekends, Hall would work children's parties, church socials, "any plate that wanted a cowboy."

Now, it's nothing but Wimpy, usually about three times a week. Hall does a Cub Scout dinner here, a gig in a shopping mall there.

Wimpy leans heavily on well-worn cowboyisms in his act. Not only are his boots, belt and hat pearly white, just like Gene Autry's, but the stand on which he stores his ropes is in the shape of a cactus.

The man himself, however, is far from Western. "Always scared to death of a horse and always figured black cows gave chocolate milk," he says.

Wimpy did spend a year and a half at a California dude ranch once, where the cowboys were real. But they wanted to learn Wimpy's rope tricks, not teach him.

So he came back to Washington and the Navy Department, "where my roots are - my family, my church," and the Beltway range Cowboy Wimpy is used to riding.

Wimpy's 25 minute act has changed little over the years. He still begins with a hearty hi-ho and one black round from a pistol aimed at the ceiling. It's guaranteed to do two things: bring folks from all over the shopping center and cause at least three babies to start crying.

Briskly Wimpy passes on to balancing his hat on the brim of his nose, spinning five lariats at once, jumping in and out of a spinning rope and giving lariat lessons to four children chosen from the audience.

The final bit is to give all the kiddies Cowboy Wimpy postcards.

Another show done, Cowboy Wimpy is walking down the mall to his dressing room. Gonna set a spell. Passing teen-agers snicker at his outfit, but he pays no attention.

"Just want to bring everyone some happiness," he says, as he passes a pizzeria. "I hope to be able to do it as long as the Good Lord lets me keep my health."