Some of the projects here are Solar Power Circuits charge control, Amateur Radio Circuits, beacon keyer, antenna tuner. Micro Power FM Broadcasting Circuits, Pulse Width Modulator PWM Circuits, motor speed controls, Geiger Counter Circuits,...
"Only a few of the circuits here rely on microprocessors. Micros can greatly enhance the power of a small device, but the specialized development tools can put the project out of reach for many hobbyists and the development systems tend to go obsolete in a short time." - Forrest Cook
It is a 3 phase motor controller. It takes a DC voltage and generates 3 sinewaves for driving a motor, conceptually similar to those small ESC for drones and bikes. The difference is that this particular setup can safely work with a 400V battery, flowing 300Amps all year long.
A Geiger–Müller tube consists of a tube filled with a low-pressure (~0.1 Atm) inert gas. (Helium, Neon, Argon,...). The GM-Tube has a coaxial shape, where the inner conductor (Anode) is biased with a high voltage (~500V) relative to the outer conductor (Cathode). The Tube has a window (left side) made of mica.
Homebrew Geiger Müller Counter - This GM-Counter is build on 2 PCB's. One is a standard high Voltage generating circuit, whilst the second is a Counter based on an ATMega16™ which also handles serial Communication with a host (Environmental Control).
Mr. EQ - A simple, yet potent DIY equalizer. Schematic, PCB/perfboard layouts, and photos.
Little Gem - Two 9v battery-powered amps based on the LM386. Schematic and PCB/perfboard layouts.
Eighteen - The Marshall 18W adapted for use as a distortion stompbox. Schematic, PCB/perfboard layouts, and photos.
Tonemender - An ultra-flexible tonestack with clean boost. Schematic, photo, and PCB/perfboard layouts.
Thor - The legendary Marshall 100W Super Lead adapted for use as a distortion stompbox. Schematic and PCB layout.
The Thunderchief project, released in March 2004, was the first runoffgroove.com circuit that was developed using the tubes-to-FETs process. Enlightened and inspired by Doug Hammond's excellent Meteor circuit, we used the same approach in an effort to capture some of the legendary magic of the Marshall Super Lead. The circuit's performance pleased us, but there were issues.
Splitter-Blend - Dual parallel buffered effect loops with blend control. Schematic and perfboard/PCB layouts.
Professor Tweed - The Fender Princeton adapted for use as a distortion stompbox. Schematic, PCB/perfboard layouts, and photos.
My Start as a Ham - Ralph's Story - "I suppose my interest in things electrical began when at a very young age I poked a metal hairpin into an electrical outlet. To this day, I vividly remember the amazing flash and bang that resulted! Of course, I wanted to know why that happened. It was a few years more before I learned to read, and found out about electricity."
The design of switching supplies is a bit more involved than traditional "big iron" transformer power supplies. When taken step-by-step, however, it is quite possible for an amateur to design and build a working high power switching power supply. This article describes a high power, high voltage switch mode power supply designed to operate a KW level RF power amplifier.
Home brew Litz Wire
The Litz wire was fashioned by taking two parallel strands of #18 AWG wire about 115 feet long and twisting them together in a clockwise direction with an electric drill until the twisted wires had about two turns per inch. The twisted wire was then cut into four equal length and laid side by side.
All Mains Inlet Sockets should be Shuttered, so that such a thing does not happen again to any child again. Another Law, No Mains Socket should be less that 5 feet above the ground level.