Miscellaneous schematics

· Ultrasonic radar

· Electronic fish lure

· Ultrasonic sound receiver

· Experimental data transmitter for fiber optics

· Experimental fiber optic receiver

· Ion detector

· Darkness monitor

· Electroscope

· Simple event counter

· Geiger counter

· Light detector

· Short-circuit beeper

· LM 1800 FM stereo decoder

· Glitch detector

· MAX924 bar-graph level gauge

· Ultrasonic generator

· Negative ion generator

· ELF Monitor

· How to generate a Rotating Field

· Chaos generator

· Simple BFO metal detector

· Voltage Comparator Information And Circuits

· Electromagnetic Levitator

· Build Your Own Digital Setting Circles For Your Astronomical Telescope

· PL tone generator (NE567)

· Bat detector

· Bat detector microphone pre-amplifiers

· DGPS receiver

· Full-duplex doorphone with 3 wires connection

· G Strain energy absorber

· RDS Encoder

· Toggle Switch Debounced Pushbutton

· RDS Encoder

· Discrete Set/Reset Flip Flop

· Monostable Flip Flops (one shot)

· Discrete Bistable Flip Flop

· Talking Morse Code Practice Computer

· Plant watering watcher

· Capacitance sensor

· Whistle responder

· Nocturnal animals whisker

· 12V DC electronic door chime

· Biasing Op-Amps into Class A

· Parasite zapper

· Analog computer

· BayComm packet modem

· Morse monitor

· HamComm modem interface

· Morse paddle keyer

· UV light box

· Voice activated tape recorder switch

· Random noise generator

· Analog pulse counter

· Analog opto-isolator

· Pulse width modulators (PWM)

· Pulse width to voltage converter

· Fantastic Atom Expander

· Black Light

· Computerize Your Room/Home

· Flash slave trigger

· A Visual CW Zero Beating Aid

· A two-way Morse practice set

· Magnetic levitation device

· Tesla power receiver

· Lazer Tag Equipment Modifications

· Pulse pperated Ni-Cd battery zapper

· Garmin GPS data interconnect

· Inexpensive APRS Weather Station

· Walking robot

· Vibrating Pocket Bug Detector

· Basic op-amp circuits

· Power line FM intercom

· Intercom circuit

· Lightning Storm Detector

· Large LCD Display Buffering Driver

· Text to speech converter

· Ion detector

· 1uS light pulse descriminator plus F to V converter (PDF)

· Broadband 2MHz optical fiber receiver (PDF)

· Modulated light received (PDF)

· 1uS light pulse receiver plus post amp (MISC)

· Broadband 5MHz optical fiber receiver (PDF)

· High-speed light receiver (PDF)

· Basement doorbell beeper (PDF)

· Time to dust indicator (PDF)

· Low-power optical interrupter (PDF)

· Simple nitrogen spark generator (PDF)

· Ultrasonic transducer oscillator circuit

· Build logic gates using discrete parts

· Jacob's Ladder

· Sudden Ionospheric Disturbance (SID) Receiver

· A selection of robotics projects

· Bat detector (new)

· Vat detector (old)

· Variety of quick designs

· Gold wafer (smartcard) programmer

· Making a FRED photopopper

· Griffith Observatory Tesla Coil

· Fogger smoke machine

· Dinsmore 1490 digital compass

· Geiger counter

· Electric field disturbance monitor

· Inexpensive seismometer project

· Digital dial

· GPS receiver interface

· Doorbell for the Deaf

· Electromagnetic field detector

· Insect Repellant

· High Quality Intercom

· Magnetic Gun.

· Metal detector

· Static Electricity / Negative Ion Detector

· Ultrasonic dog whistle

· Popular Electronics Ultrasound Detector

· An Inexpensive X-ray Machine

· Magnetic levitation circuit

· PE3342 Programmer Schematic

· Schmidt Trigger

· u-Blox GPS receiver board

· Assorted digital circuits

· Basic electronic circuits

· Miscellaneous simple circuits

· Digital Call Sign Annunciator

· Ultrasonic switch

· Sound finding cricket with phase detector

· Sound finding cricket

· APRS GPS tracker schematic (PIC16C73)

· No loss capacitor

· Discrete logic decimal to BCD converter

· Doorbell extender

· Earthquake detector

· Electromagnetic levitator

· Jacob's ladder

· Magnetic ball levitator

· Photodiode amplifier

· Relative wind angle indicator

· Solid-stateTesla coil

· Very basic circuits

· Bat detector

· FCTS Project

· Smooth Tone Clickless CW Sidetone Generator

· Morse Code Beacon Keyer

· Lightning Activated Camera Shutter Trigger

· Three Power Supplies for the Garmin GPS-20 Sensor Board

· Driving N-channel FETs from TTL

· Miniature Self-Powered Autonomous Robot

· Electronic Dazer

· Morse Code Practice Keyer 1

· Morse Code Practice Keyer 2

· 741 Light Sensor

· Fluid level detector

· The Aisin-Seiki GPS-Receiver (The "US$20 GPS")

· Voltage follower with 1G ohm input (LM11)

· Double-ended flashing voltage monitor - LM10

· Morse code display

· Intercom schematic

· Pulse Induction Metal Detector

· Scaling ADXL50 accelerometer output

READ MORE - Miscellaneous schematics

Misc audio (also see Music, Amplifiers, Preamp)

· Pink noise generator

· A Schottky-based Saw-to-Tri converter

· Saw to triangle converter

· Improved saw to triangle converter

· Voltage controllable LFO

· White noise generator

· Electronic siren

· Two-tone siren

· Underwater microphone

· Code practice oscillator

· Noise generator

· Electronic whistle

· Low Frequency Sinewave Generators

· Horror movies sound effects

· Sound amplifier

· Temperature sensitive oscillator

· Twin-T Audio Sine Wave Oscillator

· 1.5V Audio Amplifier

· Low Power Op-Amp - Audio Amp (Intercom)

· 555 Tone Generator (8 Ohm Speaker)

· 3 Transistor Audio Amp (50 milliwatt)

· Low Frequency Sinewave Generator

· Automatic Charger for Battery Operated Hi-Fi Preamps

· Audio level indicator

· Room noise detector

· Amplifier timer

· Bell ring generator

· Amplified ear

· Precision audio millivoltmeter

· Six-channel Mixer and Amplifier

· Audio Signal Source

· Analog VU meter

· Voltage controlled amplifier

· Audio graphic equaliser

· Intercom preamp

· FET audio mixer

· Microphone mixer

· Tone control

· Digital volume control

· Sound level meter

· CMOS IC audio oscillator

· Ultrasound detector

· Three band Active Tone Control

· Automatic gain control (AGC) circuits

· Audio frequency meter

· Bull Horn

· Sound Mixer/Amplifier

· Very loud beeper (PDF)

· Digital noise generator (PDF)

· Tone display system

· Tube amplifier

· Condenser microphone hookup

· Phase shifter

· Paradoxical Sound Syntheizer

· Various tube crossover circuits

· Bias circuits

· Audio line isolator

· Dynamic microphone to electret microphone input

· Line level signal to microphone input adapter

· Simple two line output combiner

· Electret microphone powering circuits

· Use amplifier phono input as line level input

· Speaker signals to line level inputs

· Spring reverb unit

· Sine wave generator

· Simple amplifier

· 3-Band equalizer

· 6-Input mixer

· Doorphone intercom

· Stereo line driver

· Audio notch filer

· Peak reading audio level meter

· Tone control

· Speaker Microphone Circuit

· Electronic canary

· Electronic siren

· Microphone phantom power supply

· NHT subwoofer amp

· Voltage Controlled Mixer w/Modulator

· Dual Voltage Controlled Oscillator w/Modulator

· Dual Voltage Controlled Filter w/Modulator

· Stereo Ducker

· MS Stereo Decoder

· MS Stereo Microphone

· RIAA Equalized Stereo Phono Preamp

· Tube active crossover

· Improved PL tone decoder

· Magnetic cartridge amplifier

· LM358 preamp

· Sound detector

· Tone detector

· Tone generator

· Warbler

· Fender Champ Replica

· Keyboard scanned 8-tone generator

· Audio test station

· Audio tone VU meter

· Pink noise generator

· Voltage Controlled Panner

· Low Noise Microphone Preamplifier

· Bridging Adapter For Power Amplifiers

· Simple Surround Sound Decoder

· Simplest Ever Amplifier Bridging

· Stereo Width Controllers

· Power Amplifier Clipping Indicator

· Phono Preamps For All

· Digital Delay Unit For Surround Sound

· Parametric And Sub-Woofer Equaliser

· High Quality Sound Mixer

· Loudspeaker Protection and Muting

· Direct Injection Box for Recording & PA Systems

· Minimalist Discrete Hi-Fi Preamp

· Signal Detecting Auto Power-On Unit

· Load Sensing Automatic Switch

· Amplifier thermal protection

· Active Sub-Woofer and Controller

· Balanced Line Driver & Receiver

· VU And PPM Audio Metering

· Variable Amplifier Impedance

· Linkwitz Cosine Burst Generator

· Low Noise Balanced Microphone Preamp

· Fast Audio Peak Limiter

· Subwoofer Equaliser

· 110 dB beeper - 74C14

· Audio output level meter

· Surround Sound Decoder Mk2

· Stereo compressor

· Audio mixer

READ MORE - Misc audio (also see Music, Amplifiers, Preamp)

Microcontroller based schematics

· PIC based packet radio encoder (PDF)

· RS485-Version of the SAB80C535-Microcontrollerboard

· PC IR receiver based on PIC16F84

· Record and play fast 1-bit sound on a PIC micro

· AT89C2051/4051scanning 7-segment display and keypad

· AT89C2051/4051 Driving dot LED

· AT89C2051/4051stepper motor interface

· AT89C2051/4051connecting dumb terminal

· Simple RS232C Level Converter using Transistors

· 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

· Atmel 89C Series Flash Microcontroller Programmer

· AT89C2051 real-time controller

· PIC12C508 Night-light saver

· AT89C2051 Night light saver

· Atmel 8051 Flash Based-Microcontroller Programmer

· AT89C2051 Digital thermometer and clock

· PIC16F84 CW decoder (PDF)

· 12C508 Smart Lock

· Build a PIC controlled DDS VFO, 0 to 6 MHz

· PIC controlled DDS VFO, 0 to 6 MHz

· Basic Stamp Lightning Activity Monitor

· TCP/IP stack and WWW server in a PIC16F84

· PIC16F84 line following robot

· PIC16C505 IR / wireless remote control

· Automatic door opener with PIC12C508

· RS485-like multi-drop bus with half duplex serial protocol

· WWWpic2 - A web server in a PIC

· PIC16F84 web server

· 50 MHz frequency counter, voltage meter & SWR/PWR indicator

· Programmer PIC16F84,12C50x and EEPROM 24Cxx

· RDS Encoder - digital part

· PIC programmer for serial port

· PIC 18 programmer (PIC18F458, PIC18F452, PIC18C252, PIC16C745, PIC18F6620, PIC18F6720)

· Freign vocabulary recollector

· Embedded system to send e-mails (small TCP/IP stack)

· Speaking clock using PIC & ISD device

· Speaking doorbell using PIC & ISD device

· Whistle detector using 8-pin PIC

· PIXpand

· PIC16F877 to IDE interface

· 68HC11 stepper motor control

· POCSAG encoder/decoder

· Network Time Protocol AVR Clock

· DS1820 Temperature Sensor Readout Unit

· Rotating Sprocket Wheel Generator (PIC16F84)

· Talking PIC - based on SP0256

· Serial to parallel converter using the AT89C2051

· AT89C2051 serial COMs to LED driver

· PIC16F877 Programmer And Development System

· DS1820 Arbiter V2.00 Schematic

· PIC18 Schematic

· PIC16C71 morse code callsign generator

· Atmel AVR programmer

· Microchip PIC ICSP implementation

· 101 AT Keyboard to ASCII Decoder using 68HC705J1A MCU

· DTMF tone decoder using Basic Stamp

· LCD Serial Terminal

· Propellor clock (PIC16F84)

· World's smallest PIC programmer

· PIC X1 schematic (PIC16F877)

· Optical sensor using PIC12C508

· Interfacing S-7800A to PIC16F877

· A Scenix (and PIC) Programmer

· MMC to PIC16F876 circuit diagram

· 8088 maximum mode SBC

· EZ80 single board computer schematic (Z80)

· Voice recording and message retrieval system

· Long-period watchdog timer

· PIC16F84 Range Finder Project

· Generate video signals in real-time using a PIC16F84

· PIC ICD

· PIC Project #1 - RS232 to I2C Interface

· Galvanic decoupling of I2C bus

· Programmer PIC16F84,12C50x and EEPROM 24Cxx

· Dual PIC16C84 prototype board

· Graphic LCD interface

· FSK modem with PIC16C84

· Talking YODA project (PIC16C84)

· PIC16F84/PIC16F87x-In-System-Programmer

· Microcontroller interface for 5KW microwave oven

· Using an I2C Serial EEPROM with a Basic Stamp 2

· PIC16F84 Based Morse Code Reader

· AVR-Based Serial Port IR Receiver

· Interfacing piezo elements to a microcontroller

· 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

· Way small web server

· PICADC - a free, PIC based "intelligent" A/D converter

· PIC-Programmer 2

· Connecting PIC12C508 8 to 93AA46 serial eprom

· KD7LMO Micro Beacon (PIC18F252)

· GPS LCD Display Project

· PIC16F84 LED chaser

· PIC micro LED projects

· AT89C2051 line-follower robot

· Night light saver (PIC12C508)

· Basic stamp interface circuits

· PIC16F84 sound controlled Christmas lights

· Microcontroller sensor and actuator interfaces

· Giant money counter (PIC16F876)

· PIC12C509 logic gate replacement for nitrogen filler

· PIC demo board

· PIC12C509 Gym Timer

· PIC LCD and Keypad driver

· PIC12C508 Phase Controller for 2kW heater

· PIC16F84 TRIAC / IGBT brightness phase controller

· PIC16F84 pulse monitor with date/time output (ZIP)

· Programmer for the 68HC705C8 MicroController

· 27c801 EPROM Programmer Project

· LCD to PIC16C54 schematic

· 68HC11 based RDS decoder

· 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

· PIC16C84 VT-52 Emulator for Linux

· Microchip PIC ICD (in-circuit debugger)

· Tony Nixons Pocket Programmer (PIC)

· PicoWeb V5.1 (AT90S8515) tiny web server

· 8051 Development System Circuit Board

· 8051 Development System Circuit Board

· Temperature controlled based on AT89CX051

· 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)

· AVR Beacon Super Keyer

· AVR Frequency Counter

· AVR Digital Voltmeter

· AVR Signal Generator

· PIC16F628 based timer

· Ser-Key 10-Key Serial Keypad Encoder

· 2-wire LCD interface using PIC16CF84

· PIC16F84 Serial I/O-expander with PicBasic

· RS 485-RPT Schematic

· AC lamp dimmer for Basic Stamp

· Microcontroller multi channel light dimmer

· PIC16C63 MIDI controlled light dimmer

· No parts PIC micro programmer

· Connecting LED to PIC Micro I/O pins (PDF)

· Microprocessor RS-232 Reset

· AT90S8515 experimenter board

· A PIC-Based Keyboard Emulator

· PIC-based robot

· ScanMate audio activated recorded

· PIC18F252 bootloader schematics

· PIC16F876 Datalogger

· GPS Repeater

· Kodak DC-20 camera interface (PIC12C509)

· Kodak DC-20 camera interface (PIC16F84)

· Remote control for Raymarine ST4000 Autopilot

· PIC programmers for parallel port

· Wisp628 ISP Microchip PIC Programmer

· Nixie clock (PIC16F876)

· Zilog Z80 thermostat embedded web server

· Picxie 2 - 8x8 Animated LED Signboard (PIC16F84) Picxie 2 - 8x8 Animated LED Signboard

· 10 tricks for interfacing to the PIC16C508

· Interfacing the PIC16C508

· PIC 5x7 display

· Analog to digital conversion notes

· Multi-chip programmer

READ MORE - Microcontroller based schematics

Medical and health related schematics

· Snore alarm electronic device

· Heartbeat transducer

· ECG Amplifier

· EKG/EEG circuit

· Radiation Dosage-Rate Meter

· Heartbeat monitor

· Cranial Electrotherapy Stimulator

· Automated crib lights

· Jogging timer

· Tan timer

· Muscular Bio-stimulator

· Pedometer

· Heart rate monitor

· ECG amplifier

· Simple lie detector

· Simple lie detector

· EEG preamp, anti alias filter and isolation circuit

· Self Contained Electromyograph (EMG)

· Cardiac monitor

· Galvanic Skin Response (GSR) Schematic

· Brain-Wave Machine

· Lie detector

· Simple lie detector

· ECG project page

· PC-based biofeedback monitor

· Pain field generator

· The ESP SIM (Sound Impairment Monitor)

· Respiration system

READ MORE - Medical and health related schematics

Lighting schematics

· Garden light switch

· DMX lighting and special effects

· Microcontroller Multichannel Light Dimmer

· Digital timer light switch

· Flashing flashlight

· Flashing road baricade for construction workers

· Hand clap lamp control

· 600W 120VAC lamp dimmer

· Radio controlled light switch

· Disco style Strobe Light

· Varying Brightness AC Lamp

· 12 Volt Lamp Dimmer

· 120VAC Lamp Chaser Using Solid State Relays

· Flashing Neons (NE-51 / NE-2)

· Sequencing Neons (NE-51 / NE-2)

· Touch Activated Lamp

· 220V Flashing lights

· Coutesy lamp

· Bedside lamp timer

· TRIAC light dimmer

· 12VDC Fluorescent Lamp Driver

· Strobe light

· Adjustable Strobe Light

· RHINO8 EL Sequencer

· Smart 12V light dimmer (PDF)

· Light Sequenced Candelabra

· Light timer

· 5W Fluorescent light intensity modulator (PDF)

· 1W Fluorescent lamp night light (PDF)

· Low-voltage light dimmer

· Light chaser

· 4-channel dimmer rack

· PIC16F873 light controller

· Disco light controller

· Neon desklamp

· Electronic night light

· Neon lamp dimmer

· 10-channel follower for Austin Hotel

· 12V Color organ and reverb unit

· 8-bit digital firing circuit

· Audio trigger circuit for light chasers

· Christmas star

· Electronic candle

· Electronic candle V2

· Fluorescent light dimmer

· Strobe light

· LED Mood Light

· LX-800 Lighting system

· Xenon Strobe Light

· Lamp flasher/dimmer

· Efficient dc lamp dimmer - 74C14

· Instrument panel lamp dimmer control

READ MORE - Lighting schematics