When you build a computer with relays and motors, but you don't realize.

If you know what it is, it's pretty easy to understand. The motor is essentially a pipeline instructing the CPU when to do what. The score counter is kind of mixture of RAM and arithmetic unit, it counts and remember.

I guess it's a 1 or 2 Hz clock speed 😀

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The step-by-step logic of old pinball machines
by Technology Connections
https://www.youtube.com/watch?v=E3p_Cv32tEo