Ultra MegaMax Dominator (UMMD) 3D printer

Mark Rehorst has a nice write-up about building his Ultra MegaMax Dominator (aka UMMD) 3D printer: Ultra MegaMax Dominator (aka UMMD) is my third 3D printer design/build.  I used much of what I learned from its predecessors, and tried a few experiments, resulting in a very high quality machine that produces very high quality prints. […]

A two channel SI5351 signal generator

DuWayne Schmidlkofer has a nice write-up on building a two channel SI5351 signal generator: After getting the sketches written for the SI5351 board written to support multiple display types, I decided I need to write one more. Now that Pete is moving the Simpleceiver to a single conversion super-het, I will have to worry about […]

Homemade EDM (electric discharge machining) machine

In this video Scorchworks demonstrates his DIY EDM (electric discharge machining) machine : My homemade plunge EDM (electric discharge machining) machine built based on the book “Build an EDM” by Robert Langolois. The book consists of a series of articles that originally appeared in The Home Shop Machinist. I deviated from the book in a couple […]

Project Hathor, a 2KV ring launcher

Check out Krux’s 2kV ring launcher, Project Hathor.  He writes: Have you ever wanted to shoot disks of aluminium forty five feet into the air at the press up a button? Do you like experimenting with high energy physics, and learn about things such as impulse generators, charge circuits, Lorentz force, electromagnetic induction, and how to […]

High voltage power supply for Nixie tubes

Limpkin has published a new build: a high voltage power supply for Nixie tubes For quite a while I’ve had this project idea in the back of my head that would involve using many Nixie tubes. These funny looking cold cathode displays were actually introduced during the 1950s and unfortunately need quite a high voltage […]

A 1-meter-diameter small transmitting loop for 7 MHz, part 1

qrp-gaijin has been working on a 1-meter-diameter small transmitting loop for 7 MHz: I’ve decided to try constructing a smaller, more traditional loop of 1-meter diameter. A smaller loop means smaller radiation resistance, and that means that small values of loss resistance become more significant. Great care must be taken in all aspects of construction to minimize […]

Mains 230VAC isolator

Jaanus Kalde has built an isolator box: Probing mains powered schematics is hard. Most oscilloscopes are earth referenced, so connecting ground probe to random spot of mains connected device will make a small explosion. Also there is the risk of electric shock by touching wrong part of the schematic while being in contact with something grounded like […]

An almost-GHz active differential oscilloscope probe (Part 3)

Christer Weinigel wrote a series of three posts about how he built a active differential scope probe which is usable up to about a GHz: This is part three of a series about building a active differential oscilloscope probe. Part 1 covered why I wanted a differential probe and the design of it. Part 2 […]

X-Carve CNC mill build log & review

Jeremy Blum writes: A few months ago, I built and reviewed the Shapeoko2 CNC mill from Inventables. Now, I’m back to review its successor, the X-Carve. The X-Carve features new-and-improved mechanics, a much sturdier spindle mounting system, and a myriad of other improvements that make it easier than ever to venture into the world of […]

Shapeoko2 CNC Mill build log & review

Jeremy Blum’s review and build-log of the Shapeoko2: I bet you thought that I only had room in my heart for one at-home manufacturing technology! 3D Printing is still my first true manufacturing love, but I’m very excited to share that I’ve started experimenting with CNC milling, too, thanks to the fine folks at Inventables. They […]