Uploaded April 2026 | Updated September 2026, 1 week ago

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I have never seen a convincing explanation of how a TTL NAND gate really works. It has a bizarre input circuit with weirdly connected dual emitter circuit. Explanations want you to believe that it functions like three diodes. But it doesn't. It's far more clever than that. How do we know? Because we built one. With a vintage Apollo component to boot.

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"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeod

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