Fail Of The Week: A Potentially Lethal Tattoo Removal Laser Power Supply

Caveat emptor is good advice in general, but in the wilds of eBay, being careful with what you buy could be life-saving. To wit, we present [Les Wright]’s teardown and very ginger power-up of…

The Short Workbench

Imagine an electronics lab. If you grew up in the age of tubes, you might envision a room full of heavy large equipment. Even if you grew up in the latter part of the last century, your idea might …

Parts We Miss: The Mains Transformer

About two decades ago there was a quiet revolution in electronics which went unnoticed by many, but which overturned a hundred years of accepted practice. You’d have noticed it if you had a m…

USB-C Power Supply Pushes Almost 2 KW

When the USB standard was first revealed, a few peripherals here and there adopted it but it was far from the “universal” standard implied by its name. It was slow, had limited ability …

A Deep Dive Into Quadcopter Controls

In the old days, building a quadcopter or drone required a lot of hacking together of various components from the motors to the batteries and even the control software. Not so much anymore, with qu…

Second Life UPS Mark II: A UPS For Low-Voltage DC Applications

When you have a whole stack of devices and appliances that all have an AC to DC adapter and which you’d like to put on an uninterruptable power supply (UPS), you could do the obvious thing an…

Repairing An HP Power Supply

One of the interesting things about living in modern times is that a confluence of the Internet and rapid changes in the electronics industry means that test gear that used to be astronomically pri…

A Nicer Controller For Cheap Power Supply Modules

These days, you can get all kinds of cheap power supply modules off a variety of online vendors. A lot of examples from brands like Juntek and Drok often have pretty poor interfaces though, with a …

USB-C For Hackers: Build Your Own PSU

What if you wanted to build your own USB-C PSU? Good news – it’s easy enough! If you ever wanted to retrofit a decent DC PSU of yours to the USB-C standard, say, you got a Lenovo/HP/Del…

Power Supplies Without Transformers

For one-off projects or prototyping, it’s not too hard to find a wall wart or power supply to send a few joules of energy from the wall outlet to your circuit. Most of these power supplies us…

Buck Converter Takes 8V To 100V

For those living before the invention of the transistor, the modern world must appear almost magical. Computers are everywhere now and are much more reliable, but there are other less obvious chang…

AC-DC Converter Is Reliable, Safe, And Efficient

When first starting an electronics project, it’s not uncommon to dive right in to getting the core parts of the project working. Breadboarding the project usually involves working with a benc…

Tearing Down And Improving A Professional Power Supply

[OZ2CPU] has an HP power supply that is about 30 years old. It looks brand new, though, and has three outputs and includes tracking for the adjustable positive and negative supply. After a quick de…

High Voltage Power Supply From USB

Those who work in different spaces may have different definitions of the term “high voltage”. For someone working on the GPIO pins of a Raspberry Pi it might be as little as 5 volts, so…

LED Driver Circuit For Safety Hat Sucks Single AAA Cell Dry

[Petteri Aimonen] created an omnidirectional LED safety light to cling to his child’s winter hat in an effort to increase visibility during the dark winter months, but the design is also grea…

A Very Tidy ATX Bench PSU

If there’s one thing that for decades of desktop PCs have given us, it’s a seemingly endless supply of relatively capable power supplies. If you need 5 volts or 12 volts at a respectabl…

Simple ATX Bench Power Supply Adds Variable Output

A benchtop power supply is a key thing to have for any aspiring electronics hacker. While you can always buy one, plenty of us have old computer PSUs lying around that could do a fine job themselve…

Rescue That Dead Xbox With An External PSU

There is nothing worse than that sinking feeling as a computer or other device fails just after its warranty has expired. [Robotanv] had it with his Xbox Series S whose power supply failed, and was…

USB Power Isolator Keeps Smoke In

Anyone who’s done an electronics project knows the most important part of any good design is making sure to keep the magic smoke inside of all of the components. There are a lot of ways to ma…