Electronics Hobby Projects
I ran some experiments on my battery powered gate sensor to reduce the time spent connecting to wifi as the ESP32 wifi radio is very power hungry and chews through batteries quickly. My project has to wake up, connect, report sensor status via MQTT then go back to sleep. The…
Catio (background for the project) TLDR: we have a gate that needs opening and closing daily, this project uses home assistant to monitor its state. We built a catio for our cat. Catching covid a week after adopting her and having a recommended 6 weeks of indoor-only to mitigate risk…
This is a work in progress, capturing several observations gleaned from some of my recent experiments and projects of varying success that use ESP32 modules and run from batteries. One project in particular uses disposable AA batteries and another uses an old-school NiCad and small solar panel (it’s a wifi…
Introduction My house was built without a penetration for the clothes dryer vent. When drying clothes, it is important to first open the window and poke the vent pipe out. Occasionally one of my housemates (or I) forget to do this, causing the laundry room to become a sauna rain indoors…
This article describes the temperature controlled fan circuit that I designed for my audio amplifier. The Amplifier A few years ago I built a new amplifier – the Ultra Low Distortion Amplifier Mk3 by Silicon Chip magazine. It’s an excellent amplifier packing 135W RMS per channel into 8Ω (200W into 4Ω) with…
Operational amplifiers (opamps for short) are a fantastic analogue circuit building block. While they were originally used for mathematical operations (hence the name) in early analogue computers, they are now mainly used for audio applications. What is an opamp? An op-amp or operational amplifier to be exact is quite literally…
What does it do? The Disco Lights project is what you get when you combine the fantastic beat detection circuitry of my ever popular beat triggered strobe light with coloured halogen lamps! In other words, four coloured lights flash in a variety of patterns in time with your music. Some…
What is it? The simple karaoke circuit takes a stereo line level audio signal from a CD player, mp3 player or similar and, in the case of most music recorded in the last 2 or 3 decades, significantly reduces the volume of the vocals without removing much of the accompaniment. …
Due to the substantial improvements in LED technology over the years, this ancient (2005) project is outdated. High voltage Xenon flash tube based strobe lights are simply not relevant in DIY applications any more when one can now purchase LED modules really cheaply that are actually a lot brighter than tube…