| Circuit | Category | Date Added | OK? | Votes | |
| Simple moisture indicator | Misc | |  | -4 |
|
| Two-tone doorbell using 555 timer | Misc | | | -4 |
|
| Momentary High Voltage Arc Circuit - can be used to Ignite a barbeque or a Gas in a Potato Gun | Misc | | | 3 |
|
| Cat or Dog Detector - can be used to control entry on a Cat or Dog Door | Misc | | | -1 |
|
| Fish caller circuit | Misc | Sep 23, 2009 | | -2 |
|
| Powerful stun gun / taser circuit diagram | Misc | Sep 23, 2009 | | -1 |
|
| Ultrasonic sound detector / sniffer | Misc | Sep 23, 2009 | | -1 |
|
| Simple Frequency Reader for conversion VFOs | Misc | Oct 05, 2009 | | 2 |
|
| Eddie's Composting Loo fan controller | Misc | Mar 09, 2012 | | 0 |
|
| Touch operated Band switch for Radio Set | Misc | Oct 25, 2014 | | 0 |
|
| Digital Remote Thermometer | Misc | Jun 26, 2009 | | 0 |
|
| Capacitive Sensor | Misc | Jun 26, 2009 | | 1 |
|
| Mains Remote-Alert - Remotely operates beeper and/or a LED via mains supply line | Misc | Jun 26, 2009 | | -2 |
|
| Touch activated switch using CD4011 CMOS NAND gate | Misc | Jun 26, 2009 | | 1 |
|
| Voice activated switch (VOX) circuit diagram | Misc | Jun 26, 2009 | | 0 |
|
| UltraSonic Radar | Misc | Jun 26, 2009 | | 0 |
|
| Nocturnal Animals Whisker | Misc | | | 1 |
|
| Insect Repellant | Misc | Sep 17, 2009 | | -2 |
|
| Digital Radar Speedometer | Misc | Oct 21, 2009 | | -2 |
|
| Electromagnetic Field Probe with Meter Output using an LF351 opamp | Misc | Oct 19, 2009 | | -2 |
|
| Missing Pulse Detector Circuit with 555 IC | Misc | Oct 03, 2013 | | -1 |
|
| Chaos generator | Misc | Jan 26, 2001 | | -2 |
|
| A Two-Way Morse Practice Set | Misc | | | 0 |
|
| Voltage Comparator Information And Circuits | Misc | Apr 27, 2003 | | -1 |
|
| Visible and Infrared Light Detectors | Misc | | | 0 |
|
| Light Activated Detector Circuit (LM393/LM555) | Misc | Sep 10, 2006 | | 0 |
|
| 10 GHz CW Radar based on a X-band Gunnplexer | Misc | | | -1 |
|
| Photodiode primer and interface circuit diagrams including photovoltaic and photoconductive modes | Misc | Mar 04, 2010 | | 0 |
|
| Full-duplex doorphone with 3 wires connection | Misc | Mar 23, 2003 | | 0 |
|
| G Strain energy absorber | Misc | Jan 01, 2003 | | 1 |
|
| Amateur weather station to APRS interface ALWXI-01 | Misc | Oct 07, 2009 | | -1 |
|
| Switch debouncer circuits including transistor, CMOS logic and a 555 timer based design | Misc | Jan 31, 2010 | | 0 |
|
| Interesesting circuits using diodes ideal for education or introductory courses on electronics | Misc | Feb 20, 2010 | | -1 |
|
| Selection of run circuits to experiment with the 4017 CMOS decade counter chip | Misc | Feb 26, 2010 | | -2 |
|
| Variety of applications using a CMOS 4001 2-input NOR gate including a PCB layout | Misc | Feb 20, 2010 | | 0 |
|
| Select of interesting electronic circuits that require only a single transistor ideal for education | Misc | Feb 20, 2010 | | 0 |
|
| Small selection of useful circuits | Misc | Feb 09, 2010 | | -2 |
|
| Marshmallow Bazooka with a PIC12F615 based capacitor discharge ignition system | Misc | May 16, 2010 | | 0 |
|
| Touch sensistive touchpad based on a PIC16F627A micro | Misc | May 24, 2010 | | -1 |
|
| Electric cockroach zapper | Misc | May 24, 2010 | | -2 |
|
| Home-Built Magnetic Levitator | Misc | | | 0 |
|
| Project for experimenting with magnetic levitation | Misc | | | 1 |
|
| Ultrasound detector | Misc | Sep 13, 2006 | | -1 |
|
| Build Your Own Video-Rate 2-photon Microscope | Misc | Sep 25, 2009 | | 0 |
|
| Sony RS-422 ADAT sync cable pinout | Misc | Sep 10, 2006 | | 0 |
|
| Garmin Foretrex 101,201, Forerunner 101,201 to Serial DB9 cable schematic pinout | Misc | Sep 10, 2006 | | 0 |
|
| Simple DTMF Repeater Controller using PIC16F84 | Misc | | | -2 |
|
| Build a Simple Bat Detector | Misc | Jan 08, 2014 | | 1 |
|
| Capacitance to Voltage conversion | Misc | | | 0 |
|
| Biasing Op-Amps into Class A | Misc | Jan 01, 2003 | | 0 |
|
| Bleeper box for time reference | Misc | May 01, 2004 | | -1 |
|
| Random noise generator | Misc | Jan 26, 2001 | | 0 |
|
| Analog pulse counter | Misc | Aug 12, 2001 | | 0 |
|
| Analog opto-isolator | Misc | Aug 12, 2001 | | 0 |
|
| Pulse width modulators (PWM) | Misc | Aug 12, 2001 | | 0 |
|
| Pulse width to voltage converter | Misc | Aug 12, 2001 | | -1 |
|
| Air flow detector using an incandescent lamp to detect airflow | Misc | | | 0 |
|
| Simple Lie Detector | Misc | Sep 01, 2009 | | 0 |
|
| Low Voltage Alarm | Misc | Sep 01, 2009 | | 0 |
|
| Rain Detector | Misc | Sep 01, 2009 | | 0 |
|
| Magnetic levitation device | Misc | Aug 14, 2002 | | 0 |
|
| Tesla power receiver | Misc | Jan 06, 2002 | | 0 |
|
| 1.9 Kilojoule Coil Gun | Misc | Nov 16, 2010 |  | -1 |
|
| A spark throwing tesla coil made entirely of garbage | Misc | Nov 16, 2010 | | 1 |
|
| Basic Homebuilt Discrete DTL gate circuits (Diode Transistor Logic) | Misc | | | 0 |
|
| Lazer Tag Equipment Modifications | Misc | Mar 23, 2003 | | 0 |
|
| Inexpensive APRS Weather Station | Misc | Aug 14, 2002 | | 0 |
|
| Induced voltage sensor delta-peak trigger for coilgun | Misc | | | 0 |
|
| Open loop pulse trigger module for coilgun | Misc | | | -1 |
|
| Optical speed trap to measure the the velocity of the projectile | Misc | | | 0 |
|
| Optical trigger module for coilgun | Misc | | | -1 |
|
| Power MOSFET module for coilgun | Misc | | | 0 |
|
| Three stage induced voltage triggered coilgun | Misc | | | 0 |
|
| Thyristor fired coilgun circuit diagram | Misc | | | -1 |
|
| Magnetic levitation project from Electronics Now, February 1996 | Misc | | | 0 |
|
| LNS Technologies Levitator Kit circuit diagram | Misc | | | 0 |
|
| Magnetic levitation project from Popular Electronics, May 1966 | Misc | | | 0 |
|
| Magnetic levitation project from Popular Electronics, May 1989 | Misc | | | 0 |
|
| Barry's magnetic levitation project | Misc | | | 0 |
|
| Barry's Coilgun Mark I circuit diagrams | Misc | | | 0 |
|
| Barry's Coilgun Mark II circuit diagrans | Misc | | | 0 |
|
| Barry's Coilgun Mark III circuit diagrans | Misc | | | 0 |
|
| Barry's Coilgun Mark IV circuit diagrans | Misc | | | 0 |
|
| Circuit diagram for Coilgun Pistol Pskov 1100 | Misc | | | -1 |
|
| 1uS light pulse descriminator plus F to V converter (PDF) | Misc | Jan 26, 2001 | | 0 |
|
| Broadband 2MHz optical fiber receiver (PDF) | Misc | Jan 26, 2001 | | 0 |
|
| Modulated light receiver circuit (PDF) | Misc | Jan 26, 2001 | | 1 |
|
| 1uS light pulse receiver plus post amp (MISC) | Misc | Jan 26, 2001 | | 0 |
|
| Broadband 5MHz optical fiber receiver (PDF) | Misc | Jan 26, 2001 | | 0 |
|
| High-speed 75MHz light receiver (PDF) | Misc | Jan 26, 2001 | | 0 |
|
| Basement doorbell beeper (PDF) | Misc | Jan 26, 2001 | | 0 |
|
| Time to dust indicator - battery powered dust indicator (PDF) | Misc | Jan 26, 2001 | | -1 |
|
| Low-power optical interrupter (PDF) | Misc | Jan 26, 2001 | | 0 |
|
| Simple nitrogen spark generator (PDF) | Misc | Jan 26, 2001 | | 0 |
|
| Op Amp Comparator with Hysteresis with SPICE simulation | Misc | Mar 26, 2011 | | 1 |
|
| Op Amp Precision Half-wave Rectifier including SPICE simulation | Misc | Mar 26, 2011 | | 0 |
|
| Single-Supply AC Inverting Op Amp amplifier with SPICE simulation | Misc | Mar 26, 2011 | | 0 |
|
| Hacking the Hot Wheels Radar Gun - includes circuit of analog front end | Misc | | | 0 |
|
| Automatic Plant Irrigation System Circuit for Watering Plants without any Human Interference. | Misc | Dec 07, 2014 | | -1 |
|
| Circuit for gold wafer card | Misc | Feb 21, 2005 | | 1 |
|
| Nokia 3310 Lcd Thermometer using DS18B20 | Misc | Feb 21, 2005 | | 0 |
|
| Lost keys finder using HCF4069 | Misc | Feb 21, 2005 | | 1 |
|
| Lightning Detector | Misc | Feb 21, 2005 | | -2 |
|
| Geomagnetic field detector | Misc | Feb 21, 2005 | | -1 |
|
| Fogger smoke machine controller | Misc | Jan 26, 2001 | | 0 |
|
| Mobile APRS / GPS tracking system | Misc | May 01, 2004 | | 0 |
|
| GPS receiver support kit | Misc | May 01, 2004 | | 0 |
|
| Circuit diagrams for making logic gates from discrete components | Misc | Oct 25, 2009 | | 0 |
|
| Lightning detector circuit diagram | Misc | Sep 08, 2009 | | 0 |
|
| 6 Pole ElectroMagnet Motor (aka Simple Brushless motor) | Misc | | | -1 |
|
| Solid State Tesla Coil and Wireless Power | Misc | | | 0 |
|
| Tesla coil construction project | Misc | | | 0 |
|
| Vareity of circuits for interfacing to/from TTL logic | Misc | | | 0 |
|
| Dinsmore 1490 digital compass | Misc | Nov 29, 2002 | | 0 |
|
| Geiger counter circuit diagram | Misc | Nov 29, 2002 | | -2 |
|
| Electric field disturbance monitor | Misc | Jan 26, 2001 | | 0 |
|
| Inexpensive seismometer project | Misc | Dec 15, 2002 | | 0 |
|
| Digg Button Kit | Misc | Oct 12, 2009 | | 0 |
|
| SIM card reader circuit diagram | Misc | Oct 12, 2009 | | 0 |
|
| Circuit for driving a liquid crystal (LCD) shutter to simply pass or block light | Misc | Dec 21, 2009 | | 0 |
|
| Lie detector | Misc | | | 0 |
|
| Three component bat detector based on a PIC12F683 microcontroller | Misc | Jun 27, 2010 | | -1 |
|
| Homemade GPS jammer using a MC145151 frequency synthesizer | Misc | Jan 17, 2011 | | -4 |
|
| Popular Electronics Ultrasound Detector | Misc | Jan 01, 2003 | | 0 |
|
| Navigator 555A radio direction finder (RDF) circuit diagram | Misc | May 01, 2004 | | 0 |
|
| Touch switches | Misc | Mar 05, 2009 | | -1 |
|
| Build your own UFO Bino-Scope unit - upgrade binoculars to become a photosensitive bino-scope | Misc | | | 0 |
|
| Color sensor circuit | Misc | | | 0 |
|
| PASCO scientific model SF-9211 stroboscope schematic (PDF) | Misc | | | 0 |
|
| u-Blox GPS receiver board | Misc | Mar 23, 2003 | | 0 |
|
| Assorted digital circuits | Misc | Mar 18, 2003 | | 0 |
|
| Basic opamp circuits | Misc | Mar 18, 2003 | | 0 |
|
| Miscellaneous simple circuits | Misc | Mar 18, 2003 | | 0 |
|
| Simple electronic keyer | Misc | | | -1 |
|
| FM Morse Code Keyer | Misc | | | 0 |
|
| Easy Morse Code Keyer Circuit | Misc | | | -1 |
|
| CW Tone Keyer | Misc | | | 0 |
|
| Digital Call Sign Annunciator | Misc | Jun 09, 2002 | | 0 |
|
| Monitor output from Motorola Oncore GPS engine in HP Z3801A in GPS Disciplined Oscillator | Misc | May 01, 2004 | | 0 |
|
| Ultrasonic switch transmitter and receiver circuit diagram | Misc | Jan 26, 2001 | | 0 |
|
| Plant Watering Watcher (moisture meter) | Misc | | | 0 |
|
| DIY Plasma Globe using an automotive ignition coil | Misc | | | 0 |
|
| DIY Tesla coil - DC Powered with Plasma Output | Misc | | | 0 |
|
| Stroboscope | Misc | Aug 17, 2009 | | 0 |
|
| Very basic circuits | Misc | Jan 26, 2001 | | -1 |
|
| Bat detector | Misc | Jan 26, 2001 | | 0 |
|
| Electronic canary doorbell | Misc | | | 0 |
|
| Electronic dazer | Misc | | | -1 |
|
| Jacob's Ladder | Misc | | | -2 |
|
| Negative Ion Detector | Misc | | | -2 |
|
| Negative Ion Generator | Misc | | | 0 |
|
| Tesla coil | Misc | | | 0 |
|
| Solid state tesla coil | Misc | | | 0 |
|
| High voltage zappers | Misc | | | -4 |
|
| Morse Code Practice Keyer 1 | Misc | Jan 26, 2001 | | -1 |
|
| Morse Code Practice Keyer 2 | Misc | Jan 26, 2001 | | -1 |
|
| 741 Light Sensor | Misc | Jan 26, 2001 | | -1 |
|
| Fluid level detector | Misc | Jan 26, 2001 | | 2 |
|
| Touch switch using transistors | Misc | | | -1 |
|
| FCTS Project | Misc | Mar 25, 2001 | | 0 |
|
| Count Accumulator for Radiation Levels (CARL) | Misc | Sep 21, 2006 | | 0 |
|
| Modifications for CDV700 Geiger Counter | Misc | Sep 21, 2006 | | 0 |
|
| Big Ear Stereo Parabolic Microphone | Misc | Sep 21, 2006 | | 0 |
|
| Ultra Low Power LCD Indicator | Misc | Sep 21, 2006 | | 0 |
|
| 12 Volt Toilet Tank Refiller circuit diagram | Misc | Sep 21, 2006 | | 0 |
|
| Morse Code Beacon Keyer | Misc | Jan 26, 2001 | | 0 |
|
| Weather station with pressure reading, relative humidity, indoor & remote temperature reading | Misc | | | 0 |
|
| Induction receiver for tracing wiring behind walls, hearing lightning and other electric discharges | Misc | | | 0 |
|
| Texas Instruments collection of differential op-amp circuits (PDF) | Misc | | | 1 |
|
| Texas Instruments collection of buffer op-amp circuits for ADC | Misc | | | 1 |
|
| Building a Hardware Random Bit Generator | Misc | | | 0 |
|
| Delayed shutter control for Kodak DC-20 | Misc | Jul 24, 2002 | | 0 |
|
| Morse code display | Misc | Jul 24, 2002 | | -2 |
|
| Circuit for temperature stabilization of a MTP3055E MOSFET | Misc | Sep 01, 2009 | | 0 |
|
| Kenwood TH-D7 NMEA GPS bug fix | Misc | | | -1 |
|
| Doorbell for the deaf that provides a delayed visual indication when a doorbell switch is pressed | Misc | Nov 27, 2002 | | 0 |
|
| Electromagnetic field detector | Misc | Jan 26, 2001 | | 1 |
|
| High Quality Intercom | Misc | Nov 27, 2002 | | -1 |
|
| Magnetic Gun. | Misc | Nov 27, 2002 | | 0 |
|
| Static Electricity / Negative Ion Detector | Misc | Nov 27, 2002 | | 0 |
|
| Ultrasonic dog whistle | Misc | Jan 26, 2001 | | 0 |
|
| Scaling ADXL50 accelerometer output | Misc | Jan 26, 2001 | | -1 |
|
| Infrasound circuits including several infrasound amplifier circuit diagrams | Misc | Jul 05, 2015 | | 0 |
|
| Ghost detector - detects if a ghost disturbs the electric field in the vicinity of the device | Misc | Jul 10, 2015 | | 0 |
|
| Lightning detector to receive static pulses from lightning at a frequency near 200 kHz | Misc | Jul 10, 2015 | | 0 |
|
| Atmospheric receiver to detect crackling static in a radio produced by lightning | Misc | Jul 10, 2015 | | -1 |
|
| Powerful buzzer for use as a doorbell or to notify others in different rooms dinner is ready etc | Misc | Jul 15, 2015 | | 0 |
|
| Powerful Security Siren - Transistors based and operates from 12V power supply | Misc | Jul 15, 2015 | | 1 |
|
| Whistle Responder - Beeps when hears your whistle, A gadget suitable for key-holders, games etc. | Misc | Jul 22, 2015 | | 0 |
|
| Water Level Indicator Using 7-Segment Display | Misc | Jul 30, 2015 | | 0 |
|
| Rainwater Storage Gauge | Misc | Jul 30, 2015 | | 0 |
|
| Cat and Dog Repeller | Misc | Jul 30, 2015 | | 0 |
|
| Inexpensive Remote Watering System | Misc | Jul 30, 2015 | | 0 |
|
| You Have Mail! Letterbox monitoring system | Misc | Jul 30, 2015 | | -1 |
|
| Environmentally-friendly Mosquito Repeller | Misc | Jul 30, 2015 | | 0 |
|
| Doorbell Memory Circuit Diagram | Misc | Jul 30, 2015 | | -1 |
|
| Plant Watering Watcher Circuit Schematic | Misc | Jul 30, 2015 | | 0 |
|
| Salt Taster Circuit Diagram | Misc | Jul 30, 2015 | | 1 |
|
| 430J Coil Gun circuit schematic | Misc | Oct 13, 2015 | | 1 |
|
| Stun gun circuit diagram and construction details | Misc | Oct 13, 2015 | | 0 |
|
| Negative ion generator circuit diagram | Misc | Oct 13, 2015 | | 1 |
|
| Circuit diagram for simple DIY induction heater | Misc | Oct 13, 2015 | | 1 |
|
| Soldering Iron Tip Preserver | Misc | Oct 22, 2015 | | -2 |
|
| Morse Code Beacon Keyer | Misc | Nov 30, 2015 | | 0 |
|
| Lighting Storm Monitor | Misc | Jul 24, 2016 | | -1 |
|
| 1 Hz to 10 MHz Voltage to Frequency Converter | Misc | Sep 07, 2016 | | 0 |
|
| Wide Bandwidth Cell Phone Jammer | Misc | Sep 07, 2016 | | -1 |
|
| 800 MHz Base Station Chaos Jammer | Misc | Sep 07, 2016 | | -1 |
|
| 800 MHz Phone Jammer | Misc | Sep 07, 2016 | | 0 |
|
| 1900 MHz Phone Jammer | Misc | Sep 07, 2016 | | 0 |
|
| GSM Phone Jammer - P2JBZ | Misc | Sep 07, 2016 | | 0 |
|
| Near-Field PCS Phone Jammer | Misc | Sep 07, 2016 | | 1 |
|
| PCS Phone Jammer | Misc | Sep 07, 2016 | | -1 |
|
| Once pulse per pushbutton press circuit diagram | Misc | Oct 02, 2016 | | 0 |
|
| MOSFET Temperature Protection | Misc | Oct 08, 2016 | | 0 |
|
| Handheld GPS Glareshield (or Dashboard) Mount with Power Supply | Misc | Oct 15, 2016 | | 0 |
|
| Radar Detector - W1SNN | Misc | Oct 17, 2016 | | -1 |
|
| Ultrasonic Proximity Detector 2xBJT | Misc | Oct 17, 2016 | | 0 |
|
| Precise Movement Meter | Misc | Oct 17, 2016 | | 0 |
|
| Proximity Detector NE567 | Misc | Oct 17, 2016 | | -1 |
|
| DC Current Monitor | Misc | Oct 20, 2016 | | 0 |
|
| Proportional Temperature Control for Gunnplexer - W4UCH | Misc | Oct 20, 2016 | | 1 |
|
| Ultrasonic Bat Receiver - M0DGQ | Misc | Oct 20, 2016 | | 0 |
|
| Measuring speed of light using an oscilloscope | Misc | Oct 20, 2016 | | -1 |
|
| 800 MHz Phone Jammer ver.A | Misc | Oct 20, 2016 | | 5 |
|