This tutorial will teach you how to use external and pin change interrupts on an AVR microcontroller. I will be using an ATmega168. The general principles apply to other AVR microcontrollers, but the specific vary greatly.
External Interrupts on an ATmega168 – [Link]
This project shows how to remote control the power of a flash unit.
If you are handy with a soldering iron, though, you might want to take a look at Domjan Svilkovic’s instructions to control your flash settings with a TV remote control. He took a cheapo flash, and added a PICaxe microcontroller that waits for ‘volume up’ and ‘volume down’ signals, then activates a set of transistors on the remote to simulate button presses. Now, where did I put my flash units… [via]
Control your camera flash with a TV remote - [Link]
Pulse Width Modulation is the most common way to control the speed of a DC motor. This project describes how to use the hardware PWM built inside PIC12F683 for motor speed control. The PIC12F683 reads analog voltage output of a potentiometer and accordingly changes the duty cycle of PWM wave to set the speed of the motor. Since the PWM duty cycle input is 8-bit and ADCs in PIC12F683 are 10 bits, only the 8 most significant bits from ADC output are used. This gives 256 different speed levels. The software is written in mikroC.
DC Motor Speed Control using Pulse Width Modulation (PWM) - [Link]
Mark Rehorst build his own Van de Graaff generator and documented the procedure on the article below. Van de Graaff generator is a device capable of producing high voltages by collecting electrostatic charges on a large metal sphere. The high voltage generated is able to make peoples hair stand up! Check the article below for construction details. [via]
DIY Van de Graaff generator - [Link]
A variable DC power supply is one of the most important tools for an electronics hobbyist. In order to carry out an experiment you need a reliable DC power source that can be varied according to the need of the experiment. Last week I felt I must have one on my workbench, and thought to make one for myself. This design is very simple but is great for powering almost all kinds electronic projects. It uses LM350 (a 3-pin IC) to generate a variable DC power supply. I would recommend to read the datasheet before doing this project.
Variable DC Power Supply (1.25 – 18V) using LM350 IC - [Link]
LED’s are great display tools. Their prices have decreased to a point where they are replacing more conventional light sources. In one sense their characteristic need for low voltages is an advantage e.g compatibility with I.C drives, but this voltage requirement can also be a disadvantage. I wanted to light some LED’s in a simple sign application, nothing fancy, but I needed to decrease the utility line voltage to a LED-compatible value for this application.
A power source for simple LED projects - [Link]
The microcontroller used is 0822 zilog encore! 8k series (soic,28pin) as shown on the figure. Is a programmable microcontroller, the functions used are the GPIO and the UART of the chip. GPIO is used on led indicators, and the UART is used for giving and reading AT COMMANDS to control the Bluetooth device.
MCU controlled Bluetooth automation with infrared sensor - [Link]
This easy as well as cheap but effective device is mainly intended for your ease to leave your fish autofed. You need no longer worry your fish would starve as this autofeeder would replace your job. This autofeeder device will expell pellets by quantity as well as time intervals as you like. Besides, making this circuit seems to be a bit entertaining as you are insisted to make it yourself and so It would develop your creativity.
Centrifugal fish autofeeder - [Link]
This circuit controls resistive and inductive loads up to 2,500W. Its main functional device is an integrated phase control circuit – Siemens TLE3103. It contains its own power supply, a zero voltage crossing detector circuit and a logic driver. An additional feature is the low voltage input to enable/disable triac firing enabling/disabling the logic driver.
2500W Phase Control - [Link]