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The world’s first tuning fork watch. The main elements are a tuning fork, a mercury cell, electromagnetic coils, and a transistor circuit in lieu of a mainspring, hairspring and balance wheel. The accurate resonant vibration (360Hz) generated by the tuning fork rotates the index wheel, which drives all the hands.
|Additional information||The watch achieved a daily error as small as 2 seconds through its high-frequency oscillation.|