Resistive load, constant-current power supplies, and a 3D printed desk lamp

Dr. Scott M. Baker published a new build: In this video, I build a 3D Printed Desk lamp. The basic design came from Thingiverse, but I repurposed my LM2576 Constant-Current design to serve as a dimmer.  It all started when I found an interesting lamp on thingiverse, which used 75mm air hose segments from another […]

Raspberry Pi based indoor air quality monitor

Dr. Scott M. Baker made this Pi-based environmental monitor and wrote a post on his blog detailing its assembly: For years I’ve followed the “uRadMonitor”, a device that does air quality monitoring and radiation monitoring. I’ve played with geiger counter projects before and frankly found them to be not very interesting. However, the idea of monitoring […]

Building the ultimate USB power distribution system

Dr. Scott M. Baker published a new build: My goals include: 1. The ability to switch each device on/off with a rocker or toggle switch 2. Current limiting capability via a fuse or similar device 3. Overvoltage protection 4. Visual indicator (LED) of operational status 5. Multiple independent outlet See the full post on his […]

Solar powered weather station

Antalife has written an article detailing the build of his a solar powered weather station: To expand my microcontroller and programming knowledge I have decided to try and make a Solar Powered Weather Station. My goal is to record parameters like: *Temperature *Humidity *Air pressure *Air quality (something to do with CO or CO2) I then hope to send […]

Simple I2S stereo decoder with amplifier

Dilshan Jayakody published a new build: In this project we build simple I2S stereo decoder with amplifier. To decode I2S data we use Princeton Technologies PT8211 16bit DAC. KA2206 audio power amplifier is used as driver stage of this system. Structure of this I2S amplifier is self-explanatory from the schematic. We select PT8211 and KA2206 […]

A transmit converter (and amplifier) for 630 and 2200 meters

KA7OEI has a great write-up on building a transmit converter for 630 and 2200 meters: As the name implies, a transmit converter takes another frequency – such as that produced by a conventional HF transceiver – and converts it to another frequency.  In my case I use an FT-817 – a low-power (5 watt) all-mode, […]

Pro mini logger project for the classroom

Edward Mallon writes: Dr. Beddow’s instrumentation class has been building the 2016 version of the Cave Pearl datalogger for more than three years, and feedback from that experience motivated a redesign to accommodate a wider range of student projects while staying within the time constraints of a typical lab-time schedule. The rugged PVC housing from […]

Solar powered WiFi weather station

A detailed instructions of how to build this weather station project by Open Green Energy: This Instructable is a continuation to my earlier weather station project. It was quite popular on the web, people around the globe made their own by following it and given valuable feedbacks for improvement.By taking consideration in to the comments and Q&A […]

The Boris Beacon – A 1mW solar powered hifer beacon

Dave Richards (AA7EE) has written an article detailing his 1mW solar-powered HiFER beacon project, the Boris Beacon: In this post from May of last year, I detailed the construction of a 1mW solar-powered HiFER beacon. I named it the Boris Beacon, in tribute to my neighbor’s cat. The beacon was never mounted permanently outside. I kept it […]

DIY Arduino based RC transmitter

  Dejan over at HowToMechatronics posted a detailed how-to on building DIY Arduino RC transmitter: Now I can wirelessly control any Arduino project with just some small adjustments at the receiver side. This transmitter can be also used as any commercial RC transmitter for controlling RC toys, cars, drones and so on. For that purpose it […]

Guitar Amp builder notes — AF power amplifier dummy load

Vasily Ivanenko has written an article detailing his AF dummy load project: I’ll describe a simple 8, or 4 Ω dummy load to test your home brew guitar power amplifiers. Low cost 16 Ω / 25W wire wound, aluminum shell, chassis mount resistors seem abundant.  I got mine on eBay.  Wire wound resistors vary in quality, design […]

Building a direct conversion receiver

Ryan Flowers over at MiscDotGeek posted a how-to on building a direct conversion receiver: In the first installment of this series, we discussed why we’re building a Direct Conversion receiver and talked about some basic ideas. In this installment, we explore what it takes to make the leap from a printed schematic to something physical […]

DakBoard family calendar with Raspberry Pi Zero W and Read Only filesystem

Scott Hanselman made this DakBoard family calendar with Raspberry Pi Zero W and wrote a post on his blog detailing its assembly: The implementation is simple genius. It’s a browser that starts up full screen (kiosk mode) and just sits there and updates occasionally. DakBoard provides the private webpage and tools to make that happen. […]

The OpenBrite Turbo controller for Vectrex

Stephen Wylie blogged about his Turbo Vectrex controller build:  The main impetus for this was to have a homebrew controller that actually featured an analog joystick, since there were few if any guides elaborating how to fashion one from an existing controller.  I acquired a couple Parallax 2-axis joysticks with breadboard mounting capability to do […]