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Geek Trivia: Pinball wizard

Who designed the first pinball tilt mechanisms?

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Few electronic innovations are as closely associated with a single application as the tilt mechanism is with modern pinball machines. Designed to serve dual roles as an anti-cheating and damage-prevention device, the tilt mechanism halts a game when a player excessively shakes or slams the pinball machine to affect play.

The very first pinball machine to feature a tilt sensor, Bally's Signal, came to market almost 70 years ago, and since that time, most major production pinball games have featured some form of tilt mechanism. Of course, the tilt sensor found inside Signal is quite different from modern designs, and users didn't originally call it a tilt device.

The first recognized tilt design consisted of a small metal ball resting on a nonconductive pedestal above a metallic ring. Inordinately jostling the pinball game shook the ball off the pedestal and onto the metal ring, thus completing a circuit that halted game play.

Because of the specifics of the design and its purpose to alert game operators to cheating and vandalism, these devices' original name was "stool pigeon." Alas, the pedestal-and-ball design was unreliable, and an improved version that used a small pendulum replaced it as early as 1935. The same pinball pioneer designed both the original and revised tilt mechanisms.


What pinball pioneer designed the original "stool pigeon" as well as succeeding pendulum-based tilt mechanisms?

Stanford engineer Harry Williams, who would later found legendary pinball manufacturer Williams Electronics, designed both the original pedestal and now commonplace pendulum tilt mechanisms.

The revised design consisted of a metal chain hung within a horizontal metal ring. If a players tilted or rattled the pinball machine, the chain would swing into the ring, completing the circuit and halting game play.

This design was more reliable than the ball-and-pedestal predecessor, which Williams called the stool pigeon. Williams rechristened his invention after he overheard early pinball players using the term "tilt."

Williams' pinball legacy is hardly limited to the tilt mechanism. He also designed the first electrically powered pinball machine. Pacific Amusements' Contact, which first appeared in 1933, included a scoring pocket with a solenoid kicker inside, powered by a dry cell battery.

If a player managed to cajole a ball into the scoring pocket, the kicker would automatically eject it, prolonging the game and allowing for higher scores. Contact proved so popular that within two years, every pinball manufacturer had adapted to the electric craze.

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The Trivia Geek, also known as Jay Garmon, is a former advertising copywriter and Web developer who's duped TechRepublic into underwriting his affinity for movies, sci-fi, comic books, technology, and all things geekish or subcultural.

About Jay Garmon

Jay Garmon has a vast and terrifying knowledge of all things obscure, obtuse, and irrelevant. One day, he hopes to write science fiction, but for now he'll settle for something stranger — amusing and abusing IT pros. Read his full profile. You can a...

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