Content for 2N3904

Simple DIY FM Transmitter

“Ever wondered how come you can just simply tune in to your favorite FM Radio Channel. Moreover, ever had the curiosity of making your own FM Station on a specific frequency? Well if the answer is Yes to any of …

Dub Siren V3 - 555 Project

“Ok - so this is going to be my last dub siren build (maybe…). This new one is an extension on the others that I have built and is definitely the best and easiest version I have designed. So what is …

FM Stereo Receiver add-on for Raspberry Pi

“Simple FM stereo receiver based on QN8035 for Raspberry Pi. The QN8035 is a stereo FM radio receiver launched by the Quintic Corporation. Compared to other popular digital FM tuners (RDA5807, TEA5767, etc.), this tuner does not seem to be …

Arduino Telephone Caller ID Unit

“CLI, also known as Caller ID and calling number delivery (CND), is a service offered by the telephone service provider to customers to obtain the calling party number and date/time of the call. The service activation and information format …

DIY Solar Charge Controller

“Make your own adjustable voltage solar charger. A solar charger is a charger that employs solar energy to supply electricity to devices or batteries. Solar chargers can charge lead acid or Ni-Cd battery banks up to 48 V and hundreds …

Simple Joule Thief

“Wikipedia says : A joule thief is a minimalist self-oscillating voltage booster that is small, low-cost, and easy to build, typically used for driving small loads. This circuit is also known by other names such as blocking oscillator, joule ringer, vampire …

Yet Another Perpetual Pendulum

“Heya. So I found people building perpetual self-exciting pendulums (pendula? pendulae?) and showing them off on youtube. Nice 🙂 So far the most elegant that I know of seems to be THIS ONE by youtube channel [TinselKoala] … which is in turn …

Circuit Board for Making Freeform Circuit Sculptures

“Intro: I find that working as an electrical engineer in a professional environment causes you to think about electrical design differently than you might in the makerspace. You learn how to do simple designs really quickly, but also have to …

Electric Puzzle Game

“1.1 What is it When I was a child I had a game like an electric puzzle that fascinated me. With that game, you could make a lot of electric circuits like radio, buzzer sounds, lights…and others. This …

Aiie! - an embedded Apple //e emulator

“A Teensy 4.1 running as an Apple //e Teensy 4.1 (600 MHz arm Cortex M7) running a full-speed Apple //e emulator. Because everyone needs one of these, right?”