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    • 1963-Jun

    Potentiometers regulate the flow of electricity, like the volume dial on a radio. In 1940, Arnold O. Beckman was unsatisfied with dials on the market, so he designed his own helical potentiometers, or helipots, for use…

    • 1950 – 1969

    This photograph is part of a series of marketing images used to demonstrate the small size of Helipot products, here by way of popcorn and unpopped kernels.

    Potentiometers regulate the flow of electricity, like the…

    • 1950 – 1969

    This photograph is part of a series of marketing images used to demonstrate the small size of Helipot products.

    • 1950 – 1969

    This photograph is part of a series of marketing images used to demonstrate the small size of Helipot products, in this case voltage regulators. The penny, minted in 1968, establishes the earliest possible date for the…