Looney Tunes whistles slide up the octave scale, abbreviated Moog tones punctuate the close air. Bells reverberate off the low ceiling, quarters jingle and muffled electronic voices emit commands recognizable only to the trained ear. This speaks the claustrophobic cacophony of one modern-day pinball arcade, tucked away in the shopping center strip that is Rockville Pike.

It is testimony to the omnipresence of computer technology in suburban play time. The din at the popular Rockville Gametime was no different last weekend than any other, except that it represented pinball for a cause, namely that of Children's Hospital National Medical Center.

Appropriately enough, the name of the machine the 16 tournament contestants were using was Xenon, the ancient Greek word for "strange." Xenon leaves the old corner-store pinball machine back where the microwave left the kitchen matches. When the early pinball machines would have lit a knob worth 100 points, Xenon now says "Enter Xenon" in a metallic male voice. When the now antiquated models would have racked up a free game, this machine becomes a hermaphrodite, croons "Xenon kiss" in a feminine voice and spits a second ball into play.

George Gill, who lives in Silver Spring, is 31. He's a pro. He's come to win. He's won pinball tournaments before.

"I've been playing for 15 years," Gill said. "I'll play about 10 hours a week, usually on my lunch hour, on weekends and nights . . . . For me, it's a hobby, a sport, competition. There aren't that many people who can beat me."

Gill has a bit more prespective on the evolution of this pastime than his teen-aged cohorts. He believes pinball began to enjoy greater popularity after release of the movie "Tommy," a rock musical about a "pinball wizard." He also points to a new big-business interest in the game.

The eyes of the tournament competitors are riveted on the spinning silver ball, with occasional darting glances at the orange, digital score display, now registering more than a million points. Gill, sweaty-faced, alternately grits his teeth and licks his lips. He "brings the ball back from the dead" (jargon for rescuing the ball just as it starts to disappear from the board) and Xenon emits a high-pitched "aahh, aahh!"

His score racks up well past the 2 million mark.

"This dude's goin' off," mutters one competitor to another.

"Go for the Gatorade, George," chides tournament organizer Michael Baglio.

But Gill, ever the pro, is unsatisfied with his performance. He scowls and gives Xenon a bang with his fist.

Chris Fries, 18, a Wheaton resident who helps support his pinball habit by delivering newspapers, steps up to confront the machine. A student at Montgomery College, Fries says he uses the game to fill his spare time, though he realizes there are other things in life.

"I used to play pinball a lot, but my parents figure I should spend my money on other things now that I'm 18," he explained.

A young woman rolls her baby carriage, with the sleeping infant bundled up inside, alongside a machine called "Flash." She and her male companion play with enthusiasm, calling out "thunder, lightning, flash!" as their scores multiply and deep bass Moog sounds growl. Somehow, the baby continues to sleep.

But on the tournament sidelines, relative quiet reigns. Xenon, it appears, is suffering a breakdown. Baglio had dismantled him/her to perform exploratory surgery. Nearby, the Stratovox video game audibly pleads, "Help me!"

Suddenly, disaster strikes. Xenon's protective glass cover slides to the floor and shatters.

After a huddle, the decision is made to continue the competition on another, similar machine dubbed Black Out.

Pressure mounts. Scores are lower now, indicative, Baglio says, of the tension at hand.

The first-place result was a predictable one if you got your odds from Baglio. Veteran Gill walked away with the blue-ribbon prize, a Rancho pinball machine. Damian Steo, 17, of Silver Spring, came in second, John Creamer was third and Chris Fries and Steven Shreiber tied for fourth place. They all received T-shirts and Frisbees. And Children's Hospital will get a check for $100.

Xenon, it turns out, was in need of "Brain surgery," in Baglio's words. But otherwise, the frenzied phonemes of Gametime's mechanical inhabitants continued to wreck havoc on the ear. Bells, Moog tunes and electronic voices. The beat goes on.