Me and my high school friend made a DC to DC converter that would give us 30 or so volts at a couple amps from a 12 volt battery. We used germanium power transistors which could not go much above 10 kHz. The Delco’s and the 2N458A’s were our favorites – we managed to push
(Read More…)
A month or so ago a guy posted a plea on the Facebook group that he had these pallets of these 12VDC, 1.5 amp switch mode wall warts and he was desperate to get rid of them or he would have to throw them in the trash. He said he would take any reasonable offer
(Read More…)
Caroline Joy Barnhart Your Kit must’ve had those “high quality” Radio Scrap components. 😆 My guess is you got one of the ITT2222 transistors. They made their plastic packaged version of the 2N2222 so that it did *not* conform to the standard E B C of the PN2222 or MPS2222. They were unpopular because they
(Read More…)
A neighbor moved a year and a half ago and was throwing out some beat up garden lights, so I salvaged them from the dumpster. They were pretty good ones 7 or so years ago when they were new, but the plastic was aging and brittle. I got a few solar cells and circuit boards
(Read More…)
I got this idea; instead of using a microphone and preamp at the end of a twisted pair, I would build a microphone, preamp and modulate a red laser with the audio and pick up the audio about ten yards away with a light detector. Notice that it runs on two 2V photovoltaic cells in
(Read More…)
I use this for holding solder while I hold the PCB and iron with my hands. I use my teeth to hold this pen.
Fab Lab = fabrication laboratory Do It Yourself. https://cleantechnica.com/2022/02/20/fab-labs-or-gigafactories-or-both/
MP3 Player To FM Radio Link (Mono) This circuit allows you to play your MP3 or any stereo audio source into a mono signal for reception on an FM radio. It has no antenna and has a range of a dozen or so meters. It operates off a 6 volt rechargeable Ni-MH battery pack but
(Read More…)
This website has a huge amount of electrostatic machine projects. Wimshurst, electrophorus, Van De Graaf, and much more. http://www.coe.ufrj.br/~acmq/electrostatic.html
I also remember those projects that used the CK722 and 2N107. The last few years I have been repairing older transistor radios with germanium transistors. I have had a few of them with bad germanium output transistors, and I’ve replaced them with silicon PNP transistors, along with a change in base bias resistors. They work
(Read More…)
