Path: utzoo!attcan!uunet!cs.utexas.edu!titan!heskett From: heskett@titan.tsd.arlut.utexas.edu (Donald Heskett) Newsgroups: sci.electronics Subject: Homemade transistors, etc. Message-ID: Date: 27 Jul 90 18:28:08 GMT Sender: news@titan.tsd.arlut.utexas.edu Distribution: sci Organization: Applied Research Laboratories, University of Texas at Austin. Lines: 18 A long, long time ago, I would guess it was the late 60's, the Scientific American "Amateur Scientist" section was all about making your own transistors at home. They were FETs, created by oxidizing organometallic compounds on a hotplate. The connections to the semiconductor were with made by hand with small pieces of osmium. Most of this is based on very stale rememberances; take it with a large grain of salt! I have some personal experience with crystal radios. Originally they used a point contact with a piece of galena, which is naturally occuring lead sulfide. I tried it using a chunk of galena from a rock collection; I wrapped the rock with bare copper wire and then made the point contact with a breadboard mounted safety pin. It seemed to work about as well as a commercial germanium diode. Up until the late '50s or early '60s you could buy a ready made galena detector from electronic suppliers like Allied and Lafayette.