A motley collection of ideas
Homemade circuits, experiments, tinker-friendly electronic ideas, and and things related to amateur radio.
Crickets are part of the pleasant atmosphere of summer evenings. And if there are no crickets, the engineer makes… I found this switch in an old electronics magazine, originally powered by a 9 V battery. Thought I’d try a solar version.
Cutting foam or polystyrene sheets with scissors or a saw is an unpleasant task, but with a hot wire, these materials are easy to slice through. You can buy hot wire cutters for just a few thousand forints, but it’s also easy to build one yourself using the transformer from an old reading lamp, a … Read more
Anyone working with electronics will eventually hold a component that you need to identify—what it is, how its legs connect, if it’s the right value, or whether it works at all. Testing with a multimeter A knowledgeable person can learn a lot even with a basic ohm-meter. Some multimeters include diode-test or transistor current gain … Read more
The JYE Tech DSO 068 is a do-it-yourself oscilloscope kit that’s easy to assemble. Anyone who can solder well, has some basic electronics knowledge, understands a little English, and owns a digital multimeter can confidently take on the task of building it. The kit’s list price is $79 (around 23,000 HUF at the time of … Read more
This gadget is actually a continuation of the glimm lamp project. No, I don’t keep horses or deer cattle, so I don’t have a light bulb. However, I do run into electric shepherds while walking through the woods, and it makes me wonder whether or not there is a jelly in it. This thing, which is barely bigger than a pocket knife, is designed to find out.
I’ve always been fascinated by gas-discharge lamps. I don’t know why—perhaps simply because they glow in the dark. Or perhaps because they don’t always shine with a steady light, but sometimes flicker a little, as if they were alive, or burning like a flame. Or maybe because it seems as though the light is created … Read more
Nowadays, in the age of semiconductor diodes, many people don’t even know what this thing is. Yet, they were used in radio and television receivers up until around 1975. Recently, at a ham radio flea market, I picked up an AEG selenium rectifier for a few forints. I started searching online for its datasheet, but … Read more
“It was still called broadcasting, and it cost a lot of money,When the first speaker excitedly sat down at the microphone.His ringing voice soared and flew far away,And in one listener, something responded:— The test was successful!”(LGT: The Radio) Today, digital technology is making its way into every area of communication and broadcasting. The crystal … Read more
This article revives a classic from Janusz Wojciechowski’s cult book Building Electronic Toys: a simple Hartley oscillator that does nothing—except beep endlessly. I once drove my father crazy with it and today it’s still a perfect tool for learning electronics. We explain how it works, show how to rebuild it, and explore Wojciechowski’s quirky ideas … Read more
The Grid Dip Oscillator (GDO) is one of the most important instruments for amateur radio constructors. It was primarily used for tuning resonant circuits, but with a bit of ingenuity, it has a wide range of applications. The following text introduces this instrument and some of its potential uses, without aiming to be exhaustive. I … Read more