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SPEECH
The Rotary dial is a 1950s telephone component that implemented pulse dialing.
A pulse is generated through the golden wires by one of the spinning gears pushing the metal contacts together to complete the circuit. In my model, the largest gear at the bottom is connected to the governor in the back that controls the recoil speed to make sure each pulse is generated in a controlled manner. Generally, 1 pulse is used for digit 1, 9 pulses for 9 and 10 pulses for 0.

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