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Hey friend, if you want a dead-simple, ultra-reliable 12 V to 220 V square-wave inverter that can swing a real 800–1000 W continuous load without fancy microcontrollers or expensive driver boards, then this exact circuit is the one I still build in 2025. I’ve made at least twenty of these over the years, and one … Read more
Hey friend, if you’ve ever needed to crank a 12V battery up to a solid 220V DC for running high-voltage gear like tube amps, electrostatic dusters, or even some industrial sensors without the bulk of a linear supply, this SG3525-based DC-DC converter is your new secret weapon. I’ve tinkered with these circuits for years as … Read more
Hey friend, if you’ve ever wanted a tiny FM transmitter that actually reaches across the house, the garden, or even the whole street with clear, loud audio, then this legendary single-transistor design is pure gold. I’ve built hundreds of these over the years, and it’s still the simplest, most powerful one-transistor FM bug you can … Read more
Hey friend, if you’ve ever wanted a proper little audio amplifier that sounds clean, pushes a real 8–10 watts into a 4 Ω speaker, and barely gets warm on a 12 V supply, then this clever hybrid Class-D design is going to make you smile. I’ve built probably twenty of these over the years, and … Read more
Hey friend, if you’ve ever needed to keep pigs out of the garden, stop dogs digging under the fence, or want the cheapest possible electric fence that still delivers a proper “don’t touch me again” zap, then this legendary one-transistor circuit is pure genius. I’ve built dozens of these over the years, and it remains … Read more
Hey friend, if you’ve ever blown up an LM317 while trying to pull more than an amp, or got frustrated because your “0–30 V” kit won’t go below 1.4 V, then this old-school but bullet-proof circuit is about to become your new best friend. This exact 1–30 V regulator built around the ancient-but-immortal LM723 precision … Read more
Hey friend, if you have ever wished for a bench power supply that actually does what the expensive lab units promise — smooth voltage adjustment from zero right up to 30 V and rock-solid current limiting all the way to 8 A — then this circuit is pure gold. I have built, repaired, and tweaked … Read more
Hey friend, if you’ve ever wanted a solid, adjustable bench power supply that can swing from 1.2 V all the way up to 35 V and still push a full 10 amps without crying, this classic UC3845 + TIP35C design is still one of the best DIY kings. I’ve built probably a dozen variations of … Read more
Hey friend, if you’ve ever dreamed of pulling in stations from Europe, Cuba, or pirate broadcasters on a radio you built with literally two transistors and a handful of parts, this little gem is going to blow your mind. I’ve been chasing shortwave signals for over thirty years, and this exact two-transistor regenerative circuit covers … Read more
Controlling the temperature of a soldering iron is essential for safe, clean, and professional solder joints. Overheated tips can damage components and circuit boards, while underheating leads to cold, unreliable connections. Commercial temperature-controlled soldering stations are often expensive, but you can achieve accurate control with a simple electronic circuit. This article demystifies a proven soldering … Read more