Eric Gunnerson writes: I’ve been working on a little ESP32 expansion board/shield for an LED project I’ve been working on. One of the nice things about the ESP32 is that it has a peripheral known as “LED control” that provides 16 independent channels of PWM for controlling LED brightness, and my project uses that capability. […]
The Acorn Master cartridge breakout board by Simon Inns: This project provides a simple breadboard adapter/breakout board for prototyping cartridges for the Acorn BBC Master and Acorn Electron 8-bit computers. The design consists of two PCBs, the first plugs into the computer’s cartridge slot and the second is designed to plug along the edge of […]
Fred writes: Recently I started work on a new board. This one will be a front door entry system, so I decided to go with something that could read my NFC implant but also had a numeric keypad for the kids (and anyone else) to use. Not everyone wants to be chipped. Crazy, isn’t it? […]
Jesus Echavarria published a new build: Here’s one of the last board I design the last year. On 2016, I develop the Dual USB Serial and I2C Converter board. Although this board works fine, it has a couple of lacks. First one, is that to use the both converters, you need two free USB ports. […]
Nava Whiteford has been working on a Multislope ADC: I’ve been playing with a multislope ADC design. Multislope ADC are often used in high end multimeters, and as I have a mild obsession with 8.5 digit multimeters, I wanted to try making a multislope ADC. See the full post on 41J blog.
Jarrett published a new build: I’ve been working on an ESP32 module. Part of the problem I’ve been seeing with inexpensive IoT dev boards, is that the design around the power system hasn’t been very good. Here’s my attempt to fix that. This is a battery-ready module with a proper lithium battery charge circuit, lithium […]
Ben Chong posted his RC2014 6809 CPU board, that is available on github. More details on his blog.
Dr. Scott M. Baker published a new build: When I was first getting started with electronics, wanted a Heathkit ET-3400 Microproccessor trainer, but could never afford one at the time. Eventually both I and the world moved on, to fancier more capable computers. However, I’ve still always wished I had an iconic trainer, complete with […]
Gaurav Singh made an open source 53132A OCXO Ultra stability time base, that is available on github: While i was working with my own GPSDO project. i need to have a frequency counter with descent stability so purchased my self a Agilent 53132A which is a 12 digit frequency counter, big brother to 53131A 10 […]
Steve Smith (G0TDJ) writes, “I successfully completed the Twin ‘T’ Oscillator, original by Mike Maynard – K4ICY. It’s a great circuit and sounds really good. Much better than a raspy 555 version. Mike has been kind enough to put a link to my project on his website.” More details at www.ProjectAVR.com.
Anfractuosity published a new build: “Acoustic cryptanalysis is a type of side channel attack that exploits sounds emitted by computers or other devices” Wavecatcher is a simple PCB that makes use of a MEMS ultrasound microphone, in order to capture audio to around 80kHz, with the goal of finding interesting ultrasound sources and playing with […]
Stylophone business card project from mitxela.com Printed Circuit Boards as a business card are a great gimmick. I’d seen ones with USB ports etched into them, which enumerate as a keyboard and then type a person’s name or load up their website. It’s just about possible to build them cheap enough to hand out as a […]
NRF52 Bluetooth Low Energy Module PCB using laser printer/silver paste method by Rich Olson. More details at nothinglabs.com.
G4FRE built a 10MHz distribution amplifier: I have had a need for a distribution amplifier for a while now. Searching around I found the design by G4JNT in Radcom, which filled my needs. I redrew the circuit for 4 outputs and had PCBs made. (if you want one contact me!) I now have the units […]
A how-to on designing a DIY Arduino PCB Pryamiduino from Bald Engineer: Continuing the DIY Arduino tutorial series, this AddOhms episode shows how to create a PCB in KiCad. I make a joke that the original design was a rectangle, which I found boring and pointless. So instead, I designed a triangle to give the board […]
Ben Katz writes: A while ago I added the hall effect encoder IC I’ve been using directly to the motor controller PCB. The controller sits directly on the back of the motor (with a magnet added to the motor shaft), and the phase wires solder straight in. I also have a pair of board-mounted XT30 […]
An open source 22mm diameter PCB project from Concretedog, that is available on github: So I posted a while back about how I had used these 22mm pcb’s I’d made in prototyping an ematch ignitor system for use in rocketry. Although I made these stackable boards so they would fit inside a popular size of […]
Jan Mrázek documented his experience experimenting with DIY through-hole plating of PCBs: I’ve been thinking about though hole plating for several years. The general procedure is simple – you have to activate non-copper surfaces (make them conductive) and then you apply standard electroplating procedure. You can find many tutorials on the internet, however, most of […]
Reviahh has published a new build, the PICKit 3 Mini: Previously, I made a Pickit 3 clone – (see previous blog post). It works well, but I have often wondered just how little of its circuitry was needed to program and debug the boards I make. For instance – I primarily use the newer 3.3V PIC32 […]
A followup to the PCB business card post, Sjaak writes: Designing a PCB business card seems to be the go-to for a hobbyist electronic engineers. Most people design either a passive PCB, USB HID/MSD device or battery powered LED frenzy. Uptill now I haven’t seen any cart that has a RFID, not even regular paper […]