Jeri’s at it again, this time, cracking open some 1N34 diodes to harvest the germanium to build a crude transistor. Before that, she does a really nice job sketching out the basic physics behind semi-conductor operation. And she does get her point-contact transistor to work. Crude, but it works! Kudos, as always, Jeri!

Make a Point Contact Transistor at Home

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Lost Knowledge: Homemade electronic components