555 Circuits
Basic circuits and information about this timer/oscillator. (11/6/2006)
555 Circuits II
Some useful circuits using the LM555 IC. (11/26/2006)
AC LEDs.
Some useful Circuits with LEDs using the AC voltage. (5/28/2006)
Computer to TV adapter.
Simple adapter to connect an old computer with CGA video graphics card to any TV. (11/26/2007)
Diode Circuits
A collection of simple but useful circuits made with silicon diodes. (6/14/2006)
Emergency Light.
A simple circuit that activates a light when the power is out. A version with a lightbulb and another with white LED light included. (6/25/2006)
Fluorescent Light.
How to build a 4-Watts Fluorescent light using a disposable camera, powered by one 1.5 Volts battery. (5/29/2006)
FM Microphone.
A micro-transmitter is so small and sensitive, it have only 8 easy-to-get parts and can be assembled in one hour. (6/3/2006)
How COLD HEAT Works?
This "Hi-tech" soldering tool looks like a miracle. Does it Really Work? (7/13/2005)
Homemade COLDHEAT.
My first attempt to build a homemade "ColdHeat" soldering tool. (7/8/2006)
How Battery-free Flashlights Works.
It sound too good to be true. Let's see how these battery-free flashlights works. (5/20/2006)
How To Make a Speaker
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. Updated! (6/14/2007)
LCD GD-1505 AP
Technical information about this LCD display. (4/22/2006)
LED Chaser.
A LED chaser using a CMOS 4017 and a 555. (5/28/2006)
Logic Probe.
An useful and easy to build Logic Probe with Pulse injector. An schematic of a "digital version" is included.
Mini Amplifier with LM386.
The LM386 is a low voltage audio power amplifier, simple and easy to build a mini amplifier with only a few components. (7/3/2006)
Ni-Cad Battery Charger with LM317
A simple circuit used to charge old Ni-Cad cells for your electronic project. A solar version of the battery charger included. (3/3/2008)
One Second Timebase.
Here are the instructions how to get one-second (1hz) pulses from a broken quartz clock. This is a precision timebase generator that can be used in any project that needs exactly one-second pulses. (6/11/2006) Updated!
PWM using 555.
A simple oscilator with PWM that can be used to control speed of motors or light intensity. (4/29/2006)
Resistors
How to read the color codes of the resistors and tips. (6 25 2006)
Displays: LED Matrix
Information for the Common Anode LED Matrix Display for SA04-11EWA, NFM-12882BEG-11, LEDM88RG (Updated 7/3/2006)
Strobe from Flash.
After using a disposable camera, you can build a strobe light (flashing light) with one simple modification. (6/2/2006)
Tachometer Circuit.
A simple tachometer circuit using one NPN transistor. (12/04/2007)
Traffic Light.
A two-way traffic light using a CMOS 4017 and 555. To be used as toy only. (4/23/2006)
Transformerless Power Supply.
Simple, low cost and easy to build power supply. Ideal for applications that doesn't requiere too much power. (5/28/2006)
Transistor LED Flasher
A simple LED flasher that uses only two transistors, one capacitor and one resistor. This basic oscillator can have other simple applications. (6/10/2006)
USB LED Light.
A simply and easy-to-make circuit, useful when working with the computer at night. (6/8/2006)
Where to get parts.
Tips to get cheap parts and some parts distribuitors than sell good and inexpensive parts. (6/10/2006)