Relay logic

A Revox has an example of a kind of logic circuit that predates digital logic but which could be replaced by a few NAND gates (integrated circuits). Instead, it uses the strange wiring harness (which the Larson cartoon refers to), to connect the relays' multiple contacts, so that the push-buttons on the deck's front panel, when pressed, cause the correct motors to operate in the correct directions. If you were to sell such a deck now, it would, like a modern car's turn signal, have a speaker, which would emit the "comfort noise" of the relays clanking over at the same time that the motor(s) started or stopped.

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