transistor cost

Ben Eater shows how to build logic gates out of transistors, including NOR gates. It is part of his clear hardware-from-scratch teaching style.

Jeri Ellsworth shows step by step how to make an NMOS transistor at home using a kiln, rust remover, spin-on dopant, eBay wafers and vinyl stickers.

Matt Risinger covers installing a Zehnder ERV fresh-air system in a tight passive house, explaining balanced ventilation, the benefits of heat recovery and the costs involved.

Dave Jones builds the Evil Mad Scientist discrete-component 555 timer kit, then tests it and explains the internal circuitry of the 555 at transistor level. He finishes with scope waveforms.