The Bulova 2140, 2141, and 2142 movements are part of the Accutron 214 Series, which launched in 1960 and forever changed the history of watchmaking. As the world’s first fully electronic wristwatch movement, the Accutron 214 was driven not by a balance wheel or quartz crystal—but by a tuning fork vibrating at 360 Hz. These variants introduced refinements and additional features while preserving the core innovation that made the original Accutron famous.
The Accutron 214 series introduced an entirely new approach to timekeeping:
A 360 Hz tuning fork, powered by a battery, vibrates continuously.
The vibrations drive an index wheel, which advances the gear train.
This results in ultra-precise timing and a smooth-sweeping seconds hand, unlike the ticking motion of mechanical watches.
The movement emits a signature “hum”—a byproduct of the fork’s vibration.
The 214 movement achieved accuracy of ±2 seconds per day, outperforming all mechanical watches of its time and even rivaling early quartz models.
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