https://hackaday.com/2014/04/26/4-bit-adder-built-from-mechanical-relays/
4-bit Adder Built From Mechanical Relays | Hackaday
Apr 26, 2014 - Would you consider this to be doing math the old-fashioned way? Instead of going with silicon-based switching (ie: transistors) this 4-bit adder uses...
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https://www.microtech-components.com/
Microtech Components (S) Pte Ltd - Relays, Mechanical Relays, Relay, Stock, Photomos Relay,...
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https://www.mcmaster.com/products/relays/operation-type~mechanical/
Mechanical-Operated Relays | McMaster-Carr
Choose from our selection of mechanical-operated relays in a wide range of styles and sizes. Same and Next Day Delivery.
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