Circuits & Schematics Beginners - 6

A homemade speaker using a plastic cup, business card, wire, magnet and some Lego blocks. I built this speaker from scratch; I was surprised of the quality of the sound. I doesn't look like a high-tech speaker but it works well. I didn't expect a ...

Tom XxTomxx14[ a ]aol.com The circuit uses a 555 timer wired as an astable oscillator and powered by the emitter current of the BC109C. Under dry conditions, the transistor will have no bias current and be fully off. As the probes get wet, a small ...

This is my very first construction with the cheap Atmel's ATtiny15 and the DS1820 thermometer. The main goal was the BIG display from the 7-segment LED modules. (And cheap + simple construction, of course...) My thermometer is really simple, but ...

David N. Warren-Smith This article is written for anyone unfamiliar with digital circuits but who would like to get some idea of what it is about. A few basic ideas including an actual working circuit will be presented in a graphical manner with ...