Note that all these links are external and we cannot provide support on the circuits or offer any guarantees to their accuracy. Also note that some of the circuits are illegal to operate in most countries, please check your local regulatory bodies if concerned. Other circuits are dangerous to construct and should not be attempted by the inexperienced.

NEW - CLICK HERE TO LINK YOUR OWN CIRCUITS OR OTHER SITES

All 2657 schematics are available on a single page here.

Microcontroller based schematics

• PIC based packet radio encoder (PDF)
  
• Simple CW Keyer based on Atmel ATtiny 2313
  
• AT89C2051/4051scanning 7-segment display and keypad
  
• AT89C2051/4051 Driving dot LED
  
• AT89C2051/4051stepper motor interface
  
• AT89C2051/4051connecting dumb terminal
  
• Motorola 68K SBC (single board computer)
  
• 8051 SBC (single board computer)
  
• 8051SBC V1.1
  
• Atmel 89 Series Device Programmer
  
• 89S52 Project Board
  
• Using the AT89C4051 as a RTC (real-time clock)
  
• Simple RS232C Level Converter using Transistors
  
• AVR Thermometer
  
• Motorola 68HC11 evaluation board
  
• C-52 EVB Robot Controller
  
• Mains clock controller using AT89C2051
  
• AT89C2051/4051 Easy-Downloader
  
• AT89C51/52/55 Easy-Downloader
  
• PIC16F84 programmer
  
• PIC16F84 miniature real-time controller
  
• Isolated RS232 for PIC16F84
  
• PIC16F84 debugging terminal
  
• MiniLOGGER V1.0
  
• Analog datalogger based on T89C51RD2
  
• MTK-85 8085 Microprocessor Training Kit
  
• Atmel 89C Series Flash Microcontroller Programmer
  
• In-Circuit PIC Loader (ISP programmer) over parallel port
  
• PIC18F2550 Project Board
  
• Atmel 89C2051 prototype board
  
• AT89C2051 real-time controller
  
• PIC12C508 Night-light saver
  
• AT89C2051 Night light saver
  
• Atmel 8051 Flash Based-Microcontroller Programmer
  
• SPI Flash Microcontroller Programmer
  
• AT89Sxx Cheap and Simple Learning Board
  
• AT89C2051 Digital thermometer and clock
  
• Tiny 2313 Project Development Board
  
• 4-Channel Timer using Atmel 89C4051 and MAX7219 display driver
  
• RS-232 to TTL Translator
  
• PIC16F84 CW decoder (PDF)
  
• Atmel ATmega128 development board
  
• Atmel AT90USB development board
  
• Atmel ATtiny26 development board
  
• TekBots universal device programmer with USB interface
  
• Serial LCD controller using a PIC16F628
  
• Several Atmel AVR programmer circuits
  
• PIC Light Chaser using PIC16C84
  
• ADC conversion using ADC0804LCN and 8051
  
• Multi PIC Programmer 5 Ver.2
  
• Ultrasonic Distance Measurement With the MSP430 (PDF)
  
• Basic Stamp based altimeter
  
• Interfacing EEPROM to a Basic Stamp
  
• Homebrew Basic Stamp project
  
• Interfacing the MAX186 8 Channel ADC to the BSII
  
• Interfacing the MAX187 ADC to the BSII to measure voltages
  
• RF remote control based on Basic Stamp
  
• 80C31 stepper motor controller
  
• (E)EProm, PIC and GAL Programmer
  
• Build a PIC controlled DDS VFO, 0 to 6 MHz
  
• Parallel AVR programmer
  
• AVR-Core V1.1 - DIP-like development board for ATmega128 processors (PDF)
  
• AVRlinx V1.1 - Development board for ATmega16, ATmega32 processors with data radio transceiver (PDF)
  
• AVRmini8 V1.0 - Development board for ATmega8, ATmega44, ATmega88, ATmega168 processors (PDF)
  
• AVRmini V2.0 - Development board for all AVR processors in 40-pin packages (PDF)
  
• AVRmini V3.1 - Development board supporting all AVR processors in 40-pin and 64-pin packages (PDF)
  
• AVRmini V4.0 - Development board with Ethernet/USB for 40-pin AVR processors (PDF)
  
• CF/IDE Adapter V1.0 - CompactFlash and IDE interface for your microcontroller
  
• USBmini V1.0 - Generic USB Full-speed interface board (PDF)
  
• PIC16F84 line following robot
  
• PIC16C505 IR / wireless remote control
  
• Automatic door opener with PIC12C508
  
• 3-wire serial LCD interface for the PIC
  
• RS485-like multi-drop bus with half duplex serial protocol
  
• LCD thermometer using PIC16F871
  
• Electronic irrigation controller based on PIC
  
• 50 MHz frequency counter, voltage meter & SWR/PWR indicator
  
• Serial LCD Controller using Microchip PIC16F628
  
• Programmer PIC16F84,12C50x and EEPROM 24Cxx
  
• PIC 18 programmer (PIC18F458, PIC18F452, PIC18C252, PIC16C745, PIC18F6620, PIC18F6720)
  
• Serial-based PIC16F84 Programmer For Windows 95/98/NT/2000/ME/XP
  
• LCD clock based on AVR Attiny2313
  
• PIXpand - TI calculator to Playstation memory card interface
  
• PIC16F877 to IDE interface
  
• 90S2313 AVR Robot Board
  
• ATmega8 based TNC with GPS and WX support
  
• Atmel AVR 90s2313 based POCSAG encoder (ZIP file)
  
• Atmel 90s2313 based TNC
  
• ATmega48 based Nixie Clock
  
• POCSAG encoder/decoder (Zip file)
  
• Rotating Sprocket Wheel Generator (PIC16F84)
  
• Talking PIC - based on SP0256
  
• Serial to parallel converter using the AT89C2051
  
• AT89C2051 serial COMs to LED driver
  
• 89C2051 microcontroller programmer
  
• PIC16F877 Programmer And Development System
  
• DS1820 Arbiter V2.00 Schematic
  
• Driving high-power loads with a microprocessor
  
• IDE interface to a Microchip PIC16F877 microcontroller
  
• PIC sonar (ultrasonic) range finding project with seven segment display using PIC micro
  
• A Real Time Clock IC (DS1307) project using the PIC micro
  
• PIC Serial LCD project - An RS232 serial LCD interface using a standard HD44780 LCD
  
• 101 AT Keyboard to ASCII Decoder using 68HC705J1A MCU
  
• Serial port I/O interface using AVR microcontroller
  
• A Scenix (and PIC) Programmer
  
• MMC to PIC16F876 circuit diagram
  
• Circuits for interfacing microcontrollers to a wide number of real-word interfaces
  
• Atmel Microcontroller based Ultrasonic Ranger
  
• Hardware Random Number Generator with an SX microcontroller
  
• 8088 maximum mode SBC
  
• EZ80 single board computer schematic (Z80)
  
• 8051 Development System Circuit Board
  
• Long-period watchdog timer
  
• Touch senstor based on Atmel AT90S2313
  
• PIC Web Server Schematic
  
• PIC ICD
  
• Tachometer Measures Very Low Frequencies (PIC16F872)
  
• Smart card programmer
  
• Jupiter card programemr
  
• PIC Project #1 - RS232 to I2C Interface
  
• Galvanic decoupling of I2C bus
  
• Ultrasonic Distance Measurer based on Freescale MC9RS08KA2 (PDF)
  
• Programmer PIC16F84,12C50x and EEPROM 24Cxx (PDF)
  
• Graphic LCD interface
  
• Interfacing a 4X4 keypad to a BS2 using a 74922 encoder chip
  
• FSK modem with PIC16C84
  
• Talking YODA project (PIC16C84)
  
• Microcontroller interface for 5KW microwave oven
  
• PIC16F84 Based Morse Code Reader
  
• T89V51CC01 Development board
  
• AVR-Based Serial Port IR Receiver
  
• SPI2CF, a fast and efficient WLAN interface for the AVR
  
• Victoria TAFE programmer (based on AT89C2051)
  
• JDM programmer
  
• PIC micro programmer
  
• Speech recognition using HM2007
  
• PIC microcontroller servo motor interface
  
• PIC micro multiple servo motor interface
  
• PIC16F84 countdown timer
  
• PIC16F873 ultrasonic range meter
  
• PIC16F873 Digital clock
  
• PIC16F873 remote display
  
• PIC16F84 stepper motor controller
  
• PICADC - a free, PIC based "intelligent" A/D converter
  
• PIC-Programmer 2
  
• PIC-Programmer 2 for PIC16C84 etc
  
• KD7LMO Micro Beacon (PIC18F252)
  
• GPS LCD Display Project
  
• PIC16F84 LED chaser
  
• PIC micro LED projects
  
• PS/2 keyboard keystroke logger based on Atmel 89C2051
  
• Electronic distance meter based on Motorola 68HC908QY4
  
• Fan timer based on Motorola 68HC908QT2
  
• Atmel AVR and 8051 series ISP programmer
  
• AT89C2051 line-follower robot
  
• Night light saver (PIC12C508)
  
• USB and GLCD expansion board for 8051 SBC
  
• Microcontroller sensor and actuator interfaces
  
• Complete Design for Giant 8-foot LCD Counter (Zip file)
  
• PIC12C509 logic gate replacement for nitrogen filler (ZIP file)
  
• PIC demo board
  
• PIC12C509 Gym Timer (ZIP file)
  
• PIC LCD and Keypad driver
  
• PIC12C508 Phase Controller for 2kW heater (ZIP file)
  
• PIC16F84 TRIAC / IGBT brightness phase controller
  
• PIC16F84 pulse monitor with date/time output (ZIP)
  
• Cheap Ultrasonic Range Finder based on PIC16F877A with a 8MHz crystal
  
• LCD to PIC16C54 schematic
  
• Acceleration monitor using ADXL202 and AVR
  
• 40+ MHz 5-digit frequency counter with an AVR 2313
  
• Interfacing DRAM to AT90S8515
  
• Temperature monitor/controller: AVR 2313 / DS1621
  
• PIC micro to ISA bus interface
  
• Linuxstamp general purpose processor module based on Atmel AT91RM9200
  
• PC to microcontroller communications using power from the PC serial port
  
• Microchip PIC ICD (in-circuit debugger)
  
• Variety of circuits for RS232 to TTL Signal Conversion
  
• Variety of circuits for TTL to RS232 Signal Conversion
  
• Tony Nixons Pocket Programmer (PIC)
  
• PicoWeb V5.1 (AT90S8515) tiny web server
  
• Atmel 89C2051 In-Circuit Programmer Schematic
  
• 8051 Development System Circuit Board
  
• 8051 Development System Circuit Board
  
• 8051 Development System Circuit Board
  
• Microprocessor using Xilinx FPGA
  
• Temperature controlled based on AT89CX051
  
• I2C LCD interface
  
• AFSK 1200 Modem based on PIC16C620
  
• PicCon - Hidden Radio Transmitter Controller
  
• PIC16F84 tone generator with source code
  
• PIC16F84 tone generator
  
• PIC16F84 tone generator (6-Bit)
  
• Designing a 4-Channel A/D (ADC) converter with the PIC12C671
  
• Ser-Key 10-Key Serial Keypad Encoder
  
• 2-wire LCD interface using PIC16CF84
  
• PIC16F84 Serial I/O-expander with PicBasic
  
• Wireless communications using a Basic Stamp and low-cost wireless data modules
  
• Digital compass using PIC16F84
  
• CASIO datalogger system based around Microchip PIC microcontroller
  
• Scriptable thermometer / thermometric controller based around a COP8-CCR9-PLC44 microcontroller
  
• Cypress PSoC based digital wallet to record secret codes and passwords securely
  
• Low cost Atmel in-system programmer
  
• Ultra low-cost programmer for AT90S family
  
• Connecting AT90S2313 with LCD display 2x16 char and 4x4 keypad
  
• Electronic safety lock based on ATtiny26
  
• 128x64 LCD Driver for AT90S2313 (ZIP file)
  
• Connecting LED to PIC Micro I/O pins (PDF)
  
• Microprocessor RS-232 Reset
  
• AT90S8515 experimenter board
  
• Multi-chip programmer for PIC microcontrollers
  
• 2-Digit Counter using the PIC12F629 chip
  
• Multi-chip programmer for Microchip PIC microcontrollers
  
• Multipurpose buffered PIC microcontroller development system
  
• TTL to RS232 adapter using 2N3906 / 2N3904 transistors
  
• ScanMate audio activated recorded
  
• PIC vacuum fluorescent display (VFD) interface
  
• PIC16F876 Datalogger
  
• Wisp628 ISP Microchip PIC Programmer
  
• WLoader - PIC16F877 application loader / bootloader
  
• Poor man's analog to digital converter (ADC) using a 2N222 transistor and a few passives (PDF)
  
• Nixie clock (PIC16F876)
  
• Atmel Mega88 Dual Temperatur meter
  
• Atmel Mega88 Temperatur meter, Type K sensor, Heat set and regulator
  
• PIC16 DemoKit3 with programmer and displays
  
• Picxie 2 - 8x8 Animated LED Signboard (PIC16F84) Picxie 2 - 8x8 Animated LED Signboard
  
• Darkroom timer using PIC16F84A
  
• 10 tricks for interfacing to the PIC16C508
  
• Interfacing the PIC16C508
  
• LED 5x7 display using a PIC microcontroller
  
• Analog to digital (ADC) conversion notes
  
• Multi-chip programmer