A DIY 18650 Powerwall with onboard BMS @ openhardware.co.za While I cannot afford a Tesla PowerWall, I’ve spent some time drawing up a PCB to house 7x 18650 cells in series. Each board has onboard Battery Management: *Overvoltage Protection (per cell) *Undervoltage Protection (per cell) *Balance Charging *Overcurrent Protection *Main pack Fuse The design files […]
Category Archives: DIY
Geiger counter Nixie clock
DIY Geiger counter Nixie clock @ medwaymakers.com: Continuing my love of vintage and interesting items, I came across a non-working DP-66 Polish Geiger counter from 1971, which I set out to re-purpose as a Nixie tube clock.
Raspberry Pi Controlled DC Load
Dr. Scott M. Baker has published a new build: In this video I build a DC Load that’s controlled by a raspberry pi. I’ve built dc loads before, but this time I decided to up the goal to supporting 100w (it actually handled 200w) using three mosfets instead of one. I drive it with a […]
Simple DIY active load
Charles Ouweland designed and built his own simple DIY active load, that is available on Github: At first I was messing about with some big resistors but then I decided it would be nice to have an “active load” that you can set to a particular current. You can buy these things for quite some […]
ESP8266 MP3 sound machine v2
Zack Lalanne writes: Last summer, I made an ESP8266 MP3 Sound Machine using ESPHome to play calming sounds when my son goes to sleep. I used ESPHome to develop the firmware so it could communicate with my Home Automation platform, Home Assistant. Well, requirements change and projects need updating. So over the holidays, I created […]
An experimental HF 6-band SSB transceiver
Peter (DK7IH) has been working on HF 6-band SSB transceiver: Part 1: Project Basic Outline Presentation Part 2: The Oscillators (VFO, LO and Testtone Osc.) Part 3: The Microcontroller (ATMega128) Part 4: Bandswitching Logical Circuits Part 5: Measuring Transceiver Data Part 6: The Receiver Part 7: The Transmitter Part 8: Transmit/Receive Switch Unit Part 9: […]
PoE-Powered VFD tube clock
Glen Akins’ PoE-powered vintage VFD tube clock: This is a vintage VFD tube clock that uses Ethernet for both power and data. The power is provided using 802.3at PoE+ and a Molex PD Jack that contains both integrated magnetics and a PoE Type 2 PD controller. The IP stack runs on a Microchip PIC18F67J60 microcontroller […]
Ionization chamber
Robert Gawron has posted an update on his Ionization chamber project we covered previously: Ionization chamber is a device to measure radioactivity level. When air’s atoms are hit by radioactive particles, an ion-pair is produced. Ions has electric charge, if they are in electric field create by positive and negative electrodes, negative ions will move […]
Simple VU-meter circuit
VU-meter circuit built on a breadboard using transistors, diodes, resistors, and LEDs @ Build Electronic Circuits: It’s basically a simple display for showing a value. It’s originally for showing signal level in audio circuits, but there’s no reason you can’t use it to show temperature, rain intensity, light level, or whatever other value you are […]
DIY cloud weather station with ESP32/ESP8266 (MySQL database and PHP)
A how-to on building cloud weather station with ESP32/ESP8266 @ Random Nerd Tutorials: Build a cloud weather station dashboard to visualize your ESP32 or ESP8266 sensor readings from anywhere in the world. You’ll see your sensor data displayed on gauges and on a table. The ESP32 or ESP8266 will make an HTTP POST request to […]
Building an extremely high powered 1-12V lab power supply on the cheap
Matthew Millman has published a new build: For a number of years now I’ve had a couple of high powered switching power supply units made by Power-One. They’re typically found in I.T. equipment and provide a single output rail of either 12 V or 48 V with a very high current rating. The other cool […]
Building your own Mini flight recorder
Pinko designed and built his own mini flight recorder: For a while a wanted to make my own flight recorder similar to the commercial altimeters but with my own requirements for functionality. In addition it needed to be visually appealing and functional in the same time … After some thinking about the design and functionality […]
Wireless quiz / game buzzers
An Arduino based remote buzzer project by Flute Systems: Base station uses an Arduino Pro Mini 5V. The reason for having 5V in this circuit is the TM1637 7-segment display. We’re using a 5V active buzzer module, two wires – signal and ground. On the left are the Adafruit PowerBoost 1000C for 5V and the […]
Building a USB-C PD power hub
A detailed instructions of how to build a USB-C PD power hub @ bitsnblobs.com About a month ago, I showed you how to create a USB power hub using a DC power adaptor like this. One of the suggestions was to use USB type C as the power source and in this post, we will […]
DIY bluetooth fidget cube
Liviu writes, “Recently I was made aware of the fidget cube. However the cube doesen’t seems to do anything so as a request from somebody, I decided to modify a bluetooth VR box controller and insert it in a cube.” More details on Do It Yourself blog.
Automatically re-connecting low-voltage cut-outs for 12 and 24 volt battery systems
KA7OEI writes: In a previous post I described a simple circuit that provided a low-voltage cut-out that could be used in a battery-operated system – see the article “A latching low-voltage disconnect for 12 volt lead-acid and lithium batteries”. That circuit – intended mostly for lithium-based batteries – required manual intervention to “reset” the device, […]
Homebrew scratch-built uBITX
Check out VU3JVX’s awesome uBITX scratch-built homebrew project. See the full post on SolderSmoke blog.
MiniTiouner DATV receiver built
Andrew Garratt blogged about his MiniTiouner DATV receiver built: The MiniTiouner uses free to download DVB-S receive and analysis software called “Minitioune” written by F6DZP. The Software is hosted on the VivaDATV forum. So I registered and downloaded the software. More details on Radio Antics blog.
Homemade injection transformer for PSU loop analysis
Adil Malik made a DIY injection transformer for PSU loop analysis: Recently, I have been designing some SMPS and required some hardware to measure the actual loop response of the complete converters. People familiar with this area will probably know this can be done breaking the feedback loop of the converter and injecting a small […]
Nano controlled step attenuator
VE3POA writes: DuWayne KV4QB, has done a Step Attenuator project and was kind enough to give me a board he designed for it at FDIM this year. So, I will not reinvent the wheel here and follow his design. Thank you DuWayne. Here’s a link to his blog where you can read not only about […]