DIY Electronics and Hardware

Ever wanted to build custom battery packs for electric bikes, solar power banks, or RC projects but found commercial spot welders too expensive? I’ve got the perfect solution! In this Instructable, I’ll show you how to build a powerful yet affordable battery spot welder from scratch. This isn’t just another simple project—it’s a professional-grade tool that uses the classic NE555 timer and parallel MOSFETs to deliver precise, controlled welding pulses.

Introduction

GitHub Link https://github.com/nmur/M5Stack-CompositeTestPatternGenerator

YT Guide: https://www.youtube.com/watch?v=iUDOLJ1Ki84

If you’ve got an old black and white TV, it’s probably not useful for much. There are precious few analog broadcasters left in the world and black and white isn’t that fun to watch, anyway. However, with a little work, you could repurpose that old tube as a clock, as [mircemk] demonstrates.

Instructables link

Designed by Nova Radio Labs in the US, the Novaduino Environmental Sensor Kit is an Arduino-programmable air quality and weather monitoring solution built around the company’s own Novaduino Display Module. It provides VOCs, eCO₂, temperature, humidity, and barometric pressure data in real time, making it ideal for Smart Home experiments, classroom projects, or hobby weather-station builds.

Over on YouTube [DENKI OTAKU] runs us through how a 4-pin MOSFET works and what the extra Kelvin source pin does.

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It's a Panasonic BQ-390 AA charger, which used to be renowned as the best "smartest" AA charger.

I am autistic and I fucking love sensors and data. I put all of them on one screen. It's like heroin for me.

Here is the code:

EZMonitor is a lightweight KDE Plasma 6 applet that displays real-time data from your solar inverter.

Code is found here: https://github.com/yucandu/desktopfps

Link to how-to: https://pejaver.com/Projects/BasementMonitor.htm