Pi-powered Atari 5200 multi-ROM cartridge (MultiCart)

Dr. Scott M. Baker has a nice write-up about building a multi-ROM cartridge for his Atari 5200 using Raspberry Pi: The Atari 5200 is a vintage gaming system from the early 1980s. At the time I owned a 2600 and was still playing bingo cash games with my friends on weekends, but I always wanted […]

Multichannel logic probe and pulsar

Dilshan Jayakody published a new build: This is 8 channel CMOS logic probe and pulsar which is useful when designing, testing and faultfinding in digital circuits. This circuit is designed using commonly available CMOS logic ICs which including couple of 4069 hex inverters and 4040 binary counter. Logic probe of this system is based on […]

A limited attenuation high-pass filter for the KiwiSDR

KA7OEI published a new build: One of the issues common with using a broad-band, direct-sampling SDR (software-defined radio) like the KiwiSDR is that of overload by strong, low-frequency signals, such as those on the AM (mediumwave) broadcast band – but there’s another problem that should be considered as well:  The high generally-high signal levels at […]

Building a DIY SMT pick & place machine with OpenPnP

Erich Styger has a nice write-up about building a DIY pick & place machine based on OpenPnP: This article is about a project I have started back in January 2018. As for many of my projects, it took longer than anticipated.But now it is working, and the result is looking very good: a DIY automated pick and […]

3D printed stirling engine gas burner and flywheel

The 3D printed Stirling Engine with its new gas burner and heavier flywheel from Do It Yourself Gadgets: Take a look at my upgraded Stirling Engine with its new gas burner and flywheel! If you take a look at my previous post you’ll see how I built a 3D printed holder for my Stirling Engine […]

TRL measurements with homemade VNA and open source software

Henrik Forstén writes: I have been using the OSH Park’s 4 layer process a lot on my own projects. It has FR408 substrate that has better controlled permittivity and lower losses than ordinary FR-4 that other low cost PCB manufacturers use. In my opinion currently it is the best low cost process for making RF PCBs. […]

Presenting the single ESC key USB keyboard

  Glen Akins shares his latest build the single ESC key USB keyboard: After building the “awesomely impractical” giant three-key keyboard, I decided it was time to build something a bit more practical—presenting the single ESC key USB keyboard! This keyboard has exactly one function which is to provide an optimal ESCing experience regardless of whatever […]

SI5351 VFO project

Dave Richards (a.k.a. AA7EE) has a nice write-up about building another Si5351 VFO project: To many, this will be just another Si5351 VFO project, with nothing to distinguish it from the others. In fact, that’s exactly what it is. The “how to” of connecting an Arduino board to an Si5351 board, wiring up a display, […]

Rombus pinball – a LattePanda mini pinball machine

Matt Brailsford (aka Circuitbeard) has a nice write-up about building his mini pinball machine with a lattepanda core running dual monitors: I generally start my projects by thinking about the hardware that I’m going to want to use as I’ll need to know sizes when it comes to the design phase. My first thought was to […]

Nickelbot – wooden nickel laser engraver

bdring posted an update on NickelBot project we covered previously: The NickelBot is complete and it works great. The goal of the project was to create an easily portable machine that creates low cost items that could be given away at events like Maker Faires. I think it has completely achieved that goal. The nickels are […]

Using DC motors to power computers

Electric generator experiment from HomoFaciens: The generators I am using are in fact geared DC motors, left over from a project with my sponsor RS Components. The modern abacuses being powered during my experiments are a Raspberry Pi Model, a SIMATIC IOT2020 and an Arduino Uno. A 2×16 characters LCD is used to display results. […]

Attiny wearable

Attiny wearable project from Facelesstech: It’s a foundation for a wearable platform. It’s a Nato watch strap threaded through a PCB with a coin cell battery holder between the PCB and the strap. While working on this design, I came across some interesting discussions about 토토사이트 and their approach to integrating security features, which inspired […]