This project DoorBell was created by Quozl . He used microcontroller PIC 16F84. A microcontroller driven doorbell circuit with features: one second instant pulse output, one second delayed pulse output, two minute lighting output, latching has been triggered indicator, processor alive indicator, ignore additional trigger for preset duration. Source: Quozl

Rickard have designed the hardware of the PIC video game system to be able to run several different kinds of games. It has two standard C64/Amiga/Atari joysticks and video and audio output. The processor is a PIC16F84 running at 12MHz and generates both video (PAL and NTSC) and audio in software.  The hardware design is [...]

This circuit is used to control a total of three independent processes: Generating video signal Revenue characters from the keyboard, decoding and sending to the serial line Revenue characters from the serial line and store into memory for display Source: Pandatron

Universal tester of semiconductor components with detection and simple control detects an unknown component and its basic parameters. Currently supports the following devices: Transistors type NPN, PNP, N-MOS, PE-MOS, ND-MOS, PD-MOS, N-JFET and P-JFET. Source:Pandatron

The following construction has just two features ideal for basic testing and troubleshooting on audio devices. Here low-frequency generator of structure / trackers offers the following uses: In function generator allows the injection of low-frequency signals in the way of audio devices such as amplifiers.Contrast,in low-frequency trackers feature allows you to listen to any low-frequency [...]

This device is fully functional sound card for PC. The main advantage of using PCM2704 against PCM2702 is much easier construction. The circuit can be powered directly from USB port. Source: diy4fun

This is a very simple and easy to build programmer for Atmel microcontrollers from AVR family. The microcontrollers must support serial programming. This programmer is connected to a PC through the RS232 serial interface and can be used with the PonyProg or Avrdude software programmer. Source: diy4fun

Yet another darkroom timer using a PIC 16F84A. All the functions are in firmware: Lamp(s) light at start of timing and turn off when timer reaches zero. A set of leds were added between the minute and second leds which blink during timer operation. 7 segment displays include tails for digits 6 and 9. A [...]

The light level can be adjusted with two push-buttons “Up” and “Down”. Controller in this application is PIC16F84 that drives BUZ11 mosfet. Dimmer is tested with a light bulb 12V/4W and mosftet didn’t get even warm (which was expected since the datasheet says: 50V/30A). Source: Elektronika.ba (niho) Forum post: Digital light dimmer

This small circuit is very simple to make,with only few components caps, resistors and the heart of this circuit is Attiny84 microcontroller running at 20MHz. Source: 5volt

I needed a solution to remotely turn on a computer. There are many hardware devices you can buy, but I thought Wake on LAN (WOL) would be the ideal solution and give me a chance to experiment with Microchips ENC28J60 Ethernet controller chip. WOL is a computer networking standard that allows a shut-down computer to [...]