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Last Updated: November 30, 2017 02:27 PM

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Safety Guard -  Protect your home appliances from voltage spikes with this simple time delay circuit. At the heart of the circuit is IC CD4060, which consists of two inverter gates for clock generation and...__ Electronics Projects for You

Salt Water Battery -  About 13 years ago, I made a salt water battery to operate a single AA battery quartz clock.  it ran for several months until I got tired of adding water to compensate for evaporation.  The batttery consisted of 5 cells each producing about 300 millivolts.  As I remember, I used 5 small olive jars filled with about a cup of water and a tablespoon of salt to create 5 cells in series each producing about 300 millivolts for a total of around 1.5 volts.  The positive electrode was made from a strip of double sided copper circuit board (about 1 inch by 4 inch) and the negative electrode was a similar sized strip of aluminum. __ Designed by Bill Bowden

Sandwich, the Line-following Robot -  This is a simple, yet sleek, line-following robot that you can reproduce in your home laboratory.  A racetrack movie appears at the end of the page.   __ Contact David Cook

Scanmate - Audio Activated Recorder -  ScanMate connects between your scanner and tape recorders (via the recorder's microphone or auxiliary input and its remote start jack). __ Designed by Tony van Roon  VA3AVR

Scanning Voltmeter with Minimum Mass Wireless Coupler -  ATMega8  A 10 bit scanning voltmeter with a Minimum Mass Wireless Coupler, based on the ATMega8.  Range to the Minimum Mass Base Unit is 10 to 15 cm.  if the voltmeter is battery operated, it can be floated from ground.   __ Designed by Dick Cappels

SCC3 12V 20A Solar Charge Controller -  The SCC3 kit is the heart of a 12 Volt solar power system, it regulates the charging of batteries from photovoltaic (PV) solar panels.  A charge controller is an essential part of any solar power system.  A 12 Volt solar power system can provide power to a wide variety of devices such as lighting systems, Ham and CB radios, car stereos, cell phone chargers, laptop computers, televisions, recording equipment, fans, water pumps and other 12V DC loads.  With the addition of a DC to AC inverter, the DC power can be converted to 120 Volts AC for running many household electronic devices. 
 __ Designed by G. Forrest Cook

SD Memory Card Interface -  SD memory cards, especially the ones under 1GB are cheap, relatively easy to interface and provide vast amounts of memory for imbedded control.   __ Designed by Luhan Monat - Mesa Arizona

Sealed Jar Lamp -  PIC  Project  This device uses 2 AA alkaline batteries to power a 1 watt LED.  it has 4 power levels, plus on/off, and can run either side up.  The jar light is entirely sealed with no external switches.  An internal mercury switch controls all of the modes of operation.  it will work under water.  All components are mounted directly to the circuit board (mouse over image above).  A small piece of 1/4 inch board is glued to the inside of the lid.  The circuit board is fastened to this with 2 small wood screws.  Nothing penetrates the lid.   __ Designed by Luhan Monat - Mesa Arizona

Secret Bell -  Many people move through the corridors and steps in multistoried buildings.  As most of them are strangers for the inhabitants of the flats, it becomes necessary to verify the identity of...__ Electronics Projects for You

Secure Digital Access System using Ibutton -  Access control forms a vital link in a security chain.  Here we describe a secure digital access system using iButton that allows only authorised persons to access a restricted area.  The iButton...__ Electronics Projects for You

Secure Wiring with Straws! -  Schematic + info + pictures __ Designed by Lennie Zink

Self-Announce for Electric Gates -  The electric gate in many shops, factories (not to mention cooperative apartment houses) is kept open during working hours.  This circuit detects when someone traverses the gate, ringing the bell in a very peculiar way.   __ Designed by Projects & Ideas from Nutchip.com

Self-hosting VAX C Compiler -  Not strictly my own, as it was a two-person project, done together with a CS student named Peter Mielke.  in 1990, in fourth year university, we Computer Engineering students were permitted to take fourth year Computer Science elective courses.  Perennial favourites __ Designed by Markus Wandel

Sequential Timer for DC Motor Control -  Most industrial processes require rotation of the motors in forward and reverse directions for desired periods.  One good example is the automated bottle filling plant.  Here the bottles move on a...__ Electronics Projects for You

Serial input 4 Digit Readout -  PIC  Project  This device uses an LTC4625 4 digit LED display (with RH decimal points) , along with 2 extra LED's.  it requires only 5 volts, TTL serial input, and Ground on a 3 pin connector.  Note: the connector is mounted with the pins sticking out the back side to allow for mounting flush against a (transparent) front panel.   __ Designed by Luhan Monat - Mesa Arizona

Serial Interface & bias supply for Seiko-Epson G1206B dot Graphics display -  A serial interface and bias supply for the Seiko-Epson G1216N000 using an AT90S2313 because there just aren't enough applications examples for this display on the web.   __ Designed by Dick Cappels

Serial Interface for Truly MTC-C162DPLY-2N, 2 line X 16 char LCD display -  A serial interface and bias supply for the Seiko-Epson G1216N000 using an AT90S2313 because there just aren't enough applications examples for this display on the web.   __ Designed by Dick Cappels

Serial to PIC Interface -  One of the first things I like to do when creating a new project is to get the i/O working.  This helps in debugging the code as I write it.  What about projects that do not have i/O? This device sneeks both input and output from your computer (terminal program) to the PIC  using just one pin.   __ Designed by Luhan Monat - Mesa Arizona

Servo Pulse to Dual H-Bridge -  interface performs vital control functions needed for propulsion and steering of a fighting robot __ Designed by Bob Blick

Servo Pulse to PWM -  converter connects an H-Bridge to radio control receivers or robotic circuits __ Designed by Bob Blick

Shutter Guard -  This sensitive vibration sensor is exclusively made for shops to protect against burglary.  it will detect any mechanical or acoustic vibration in its vicinity when somebody tries to break the shutter...__ Electronics Projects for You

Simple  RF Based Code Lock -  This simple radio frequency (RF) based code lock incorporates a pair of 433MHz ready made RF transmitter and receiver modules.  it is a remote-controlled and code-protected locking system.  The code is...__ Electronics Projects for You

Simple Circuit Aircraft Receiver -  This low cost, 117-137 MHz Aircraft Band Receiver was designed to receive and decode ACARS data via PC control.  The receiver consists of a tracking input bandpass filter, single conversion mixing stage, Crystal and Ceramic iF filter stages, PLL synthesized LO, RF / iF AGC circuits, data slicing circuit, audio output stage -- all controlled by a PIC  Microcontroller.  The interface to the PC is via a 9600 Baud RS232 link. __ Designed by Steve Hageman

Simple Circuit Arc Transmitter -  i have always been facsinated with the old Arc transmitters of the early period of wireless radio.  Not to be confused with Spark Gap transmitters, the Arc transmitter was different and was supposed to produce a continuous wave signal that could be sound modulated.  What follows is a description of a crude circuit that I built.   __ Designed by Nyle Steiner K7NS

Simple Circuit BFO Metal Detector -  BFO (beat frequency oscillator) metal detectors use two oscillators, each of which produces a radio frequency.  One of these oscillators uses a coil of wire that we call the search loop.  The second oscillator uses a much smaller coil of wire, and is usually inside the control box and is called the reference oscillator.  By adjusting the oscillators so their frequencies are very nearly the same, the difference between them is made audible as a beat note __ Designed by Essex Metal Detectors

Simple Circuit Class a Amplifier-10W audio output -  This page describes an antenna, a 1 watt final output stage, and a transformation network for radio experiments at 187 kHz __ Designed by J. L. Linsley Hood, M.I.E.E.

Simple Circuit Colour Organ -  This is a simple, one lamp colour organ.  it is far less complicated then the Three Channel Colour Organ.  it is simply a lamp controlled by an SCR.  it can be built in a few minutes, and combined with other circuits to make some pretty neat effects.   __ Designed by Aaron Cake

Simple Circuit FM Stereo Transmitter -  (ATTiNY12, ATTiNY25, ATtiny2313, AT90S2313, AT90S232, or nearly any other CMOS microntroller-Yes probably even a PIC !) This project appeared in the December, 2007 issue of infoElektronika Magazine __ Designed by © Richard Cappels

Simple Circuit Homemade Coherer -  The coherer was one of the first detectors of radio signals ever used 100 years ago.  I tried building one.  Getting impressive results turns out to be much easier than I have always thought.   __ Designed by Nyle Steiner K7NS

Simple Circuit LM335 thermometer -  The circuit consists of two parts: The LM335 and its adjustment.  The output of the LM335 is 10 millivolts per degree C, with 25 degrees C corresponding to 2.982 VDC.  A reference circuit provides a zero reference voltage.  it is adjusted to (2.982 volts - (25 degrees x 10 millivolts/degree) = 2.732 volts.  To read the temperature of the LM335 directly in degrees C, connect the + lead from a high impedance DVMto the output pin and the - end of the DVM to the 2.732 volt pin.   __ Designed by Dick Cappels

Simple Circuit Metal Detector -  Two transistors and a LM386 make a simple metal detector suitable for finding coins.   __ Designed by Steve Hageman

Simple Line-Following Robot -  Generally, line follower robot is microcontroller-based.  Here we describe a line follower robot without microcontroller for those who are not familiar with microcontrollers.  it is a simple project, which can be...__ Electronics Projects for You

Simple Short-Wave Transmitter -  This low-cost short-wave transmitter is tunable from 10 to 15 MHz with the help of ˝ Jgang condenser VC1, which determines the carrier frequency of the transmitter in conjunction with inductor...__ Electronics Projects for You

Simplest LED Flasher -  This may be the simplest LED flasher circuit you can build, with the notable exclusion of LEDs with integrated flashing circuits.  This might be a good replacement for the LM3909 in some applications. 
 __ Designed by Dick Cappels

Single & Two Cell White LED Drivers Without Inductors -  The operating voltage of white LEDs coupled with my emotional need for low cost for a given function, motivates me to make LED drivers suitable for battery operated lanterns that can run from a small number of cells.  White and Ultraviolet LEDs __ Designed by Dick Cappels

Single Pulse Voltage Multiplier -  Sometimes it's necessary to generate a higher voltage pulse from logic circuits than the circuits themselves can supply.  The need to generate a programming pulse for Atmel flash controllers was one of those.  in that case, I needed to generate an infrequent pulse that __ Designed by Dick Cappels

Single-Channel Remote Control -  A simple but effective remote control, capable to compete (and sometimes to beat) most ready-made units.  Plus application examples for remote door opening, remote-triggered timers, and on/off contact closures.   __ Designed by Projects & Ideas from Nutchip.com

Smart Solar Charger -  Here we present the circuit of a highly efficient, automatic solar charger based on PIC 16F877A microcontroller. it shows the system status on an LCD and can trickle charge. __ 01/22/2016 - EYI

Smartcard Controlled Relay -  Like in the spy movies, the door opens inserting an electronic card!  Very useful also to access private parks, enable photocopiers, activate showers and night light in sport resorts shared between clubs.  At last, a legal and useful application for the (otherwise vituperated) satellite-TV cards.   __ Designed by Projects & Ideas from Nutchip.com

SMT Desoldering Station -  Working with SMT is quite difficult without an smt hot air pencil.  Anyone with basics electronics can try to build it, it's made with common materials.   __ Designed by Alfred73

Soccer Robot -  This soccer robot can move forward, reverse, forward-left, forward-right, reverse-left and reverse-right with the help of an Android phone. The speed of its movement is controlled by the angle of rotation of the phone. The robot also kicks a ball when the phone is shaken__ 01/22/2016 - EYI

Solar Charger -  PIC  Project  The previous version of this device used pulse width modulation (PWM) to control the power from the five solar panels to charge the battery bank.  Under full sun conditions the MOSFETS got a bit warm and the whole unit radiated a lot of RFi.  This design uses a set of relays, one for each panel.  if the controller decides the battery voltage is too low, it engages another relay;.)  __ Designed by Luhan Monat - Mesa Arizona

Solar Light for a Portable Toilet -  Despite being more expensive than standard permanent outdoor toilets, portable toilets (Fig.1) have several significant benefits as these are self-contained and can be placed almost anywhere.  These days portable toilets...__ Electronics Projects for You

Some test equipment to build -  amateur radio construction projects.   __ Designed by Peter Parker

Sonar Water-Level Meter -  Three-fourths of the earth is water, out of which 97 per cent is saline (in oceans, seas and groundwater).  The remaining 2.5 per cent to 2.75 per cent is fresh water, ...__ Electronics Projects for You

Speech Synthesizer Development System -  This system was designed to facilitate the development of a low cost speech module using a PIC  and some EEPROM memory.  This has already been done (see PIC Talker) using 64k of memory.  So far, this device is working with only 11k of memory by using techniques discussed below __ Designed by Luhan Monat-Mesa Arizona

Spydar 2 -  PIC  Project  This is a circuit monitoring device.  it runs for over 10 days and can log up to 32k events both digital and analog.  Samples are logged either on a timing basis (.01 to 2.5 seconds) , or on a triggered basis.  Four inputs are provided, up to three of which can be analog __ Designed by Luhan Monat - Mesa Arizona

StaIR Lights -  Cat coming down the stairs after activating the top stair beam sensor which turned the LED stair lights on.  When the lights are off and it is dark outside these lights are this cat's best friend.   __ Designed by Alan Parekh

Start-Stop Button -  The schematic diagram is similar to the one shown in our previous article, with the addition of two key (SW1 and SW2) connected to inputs iN1 and iN2.  This is all we need to test the circuit; later we can add a relay in addition to the LED, in order to drive more meaningful load - like an electric motor or a lamp __ Designed by Projects & Ideas from Nutchip.com

Static Electricity Flyers -  Fly and Levitate Objects With Static Electricity.   __ Designed by Nyle Steiner K7NS

Stirling Prayer Engine -  built with simple parts and runs from the heat of a votive candle.   __ Designed by Bob Blick

SubLight -  So , the project resulted in: Acrylics pipes with 22mm acrylics ends , with O-rings , 4Mhz RiSC Microprocessor that works at 4-5 volts , 28Volt DC-DC pump , 2 optically isolated PWM outputs that uses the 28volts to control 50Ampére low-drop power MOS-FET's so fast that the MOSFET's does not require any cooling as they "never" are in linear state.  A 2x16 Character LCD display had to be added.  There are no moving parts going thru the box , the 3 buttons and on/off are magnetically controlled and does not represent a weak point (or should I say leak point ?) __ 

Super Remote -  Using a PIC 12F683 and a few transistors, it is theoretically possible to boost the power to a standard 433 MHz remote transmitter module. (Note hypothetical image at right)  __ Designed by Luhan Monat - Mesa Arizona

Superhet/Direct Conversion AM receiver for 181.818 kHz  -  This is a description of an experimental AM receiver for VLF.  it is crystal controlled to receive 181.818 kHz (more or less) and operates as either a single conversion superhetrodyne or a direct conversion receiver.  The bandwidths are expected __ Designed by Dick Cappels

Superprobe -  The Superprobe project was designed to see how much could be done with a PIC  chip and just a few parts.  The image at the right shows the capacitance measuring mode.   __ Designed by Luhan Monat - Mesa Arizona

Sweet! the Line-following Robot -  An m&m's candy container provides a fun body for a smart line-following robot.  Videos show the auto-contrast, dark-or-light detection capabilities.  Sharp turns and crossovers don't slow this car down, but it can automatically stop at the end of the line.   __ Contact David Cook

Switch Transmitter -  A door which opens, a drawer slides out, a switch turned on or a letter in your mailbox: this transmitter can detect all!  it is battery operated and can be placed practically everywhere.  Uses a single long-lasting battery.   __ Designed by Projects & Ideas from Nutchip.com

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Electronic Construction Projects: 
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