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The Counterfeit Coin Detector Patent Archive

Every device ever patented to catch a bad coin

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1890s coin mechanism

Mechanical drawing of a coin-controlled phonograph mechanism showing a vertical coin tube with numbered levers, a hinged door, springs, and a handle arm for testing deposited coins.

COIN-CONTROLLED DEVICE FOR PHONOGRAPHS.John F. Ott · July 12, 1892

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