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Last Updated: December 31, 2017 06:44 AM

Capacitance Proximity Switch
Draws very low power - Ideal for battery-powered applications
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Links to electronic circuits, electronic schematics, designs for engineers, hobbyists, students & inventors:

Laser Link Communicator -  Audio transmission up to few hundred meters - There's something rather futuristic about talking 'over' a laser beam, which is what this inexpensive project allows.  it will easily give a communication distance of several hundred metres, and with a parabolic light reflector, up to several kilometres.  it transmits high quality audio and the link is virtually impossible for anyone else to tap into.   __ Designed by Peter Philips, ELECTRONICS Australia, July 1997, page 62

Lazy ISP Adaptor for Socketed AVR ISP Controllers -  The Lazy Adapter is composed of a 20 pin DiP socket, a 20 pin DiP header, and 6 pin iSP header, and a small phenolic circuit board to hold them all together.  The green fiberglass PCB is a Dontronics DT104 SiMSTIC  (This plug is in return for a favor.)  __ Designed by Dick Cappels

LC Determination by Resonant Frequency Measurement ATtiny2313, AT90S2313 -  A well known L/C measurement circuit is pressed into service to make a bare bones measurement circuit.   __ Designed by Dick Cappels

LCD Display with Minimum Mass Wireless Coupler -  its an adaption of the 2X 16 LCD project, by adding a fettite loop antenna, two resistors, and a capacitor.  Here the display shows the output of the 10 bit scanning voltmeter with Minimum Mass Wireless Coupler.    (ATtiny2313, AT90S2313)  __ Designed by Dick Cappels

LCD Serial Terminal -  has RS-232 serial in/out, up to 20 programmable keys, Character LCD up to 2x40, 5 auxiliary inputs, 6 auxiliary outputs __ Designed by Bob Blick

LED Flasher -  A SHORT COURSE in three designs to learn how to use Nutchips from ground up.  You will start making LED flashes.  You will continue learning how to switch outputs with separate START and STOP buttons.  in the last instalment, you will learn how to remotely switch a light on and off.   __ Designed by Projects & Ideas from Nutchip.com

LED Lighting Effects -  The original yoyo was equiped with 2 LEDs that lit up when device was spinning.  I decided to add a micro to give it some extra pazazz.  The trick here is to makeunit work without a power switch.  The mercury switch is positioned so that it supplies power when unit is spinning.  After about 20 seconds, PIC  shuts down in sleep modes,  __ Designed by Luhan Monat-Mesa Arizona

Lightning - Create an electrical storm in a light bulb -  The Lightning Bulb circuit uses a quadrac (see Fig.1) --a device that combines a TRIAC and a diac trigger in a single package--to control the supplied current.  Figure 1A shows the schematic symbol for the quadrac, while figure 1B shows the pinout for the unit used in our circuit.  Note that quadracs are increasingly difficult to come by;.   __ Designed by Vincent Vollono

Li-Ion Charger -  PIC  Project  Lithium ion batteries pack a lot of power by weight compared to other types.  There are 2 things that need to be handled differently than NIC ad on NiMH
: __ Designed by Luhan Monat - Mesa Arizona

Litter Box -  PIC  Project  Not every new use of technology requires a microcontroller.  This one uses a 12 volt computer fan from CompUSA, a snap close food box from Walmart, some PVC pipe from Home Depot, and a large plastic storage container from Big Lots.   __ Designed by Luhan Monat - Mesa Arizona

Little More Serious Frequency Meter/CounterATtiny2313, AT90S2313 -  Maximum input frequency is specified to be 30 MHz in the multi-chip configuration, and in single-chip configuration, there are both 5 MHz and 10 Mhz versions operating with 10 and 20 MHz crystals, respectively.  All versions have 9 1/2 digit resolution.  I have used __ Designed by Dick Cappels

Lock-In Milliohmmeter -  A milliohmmeter is just the tool for checking trace resistance on a printed circuit board, tracking down shorted traces, and measuring the contact resistance of a switch or connector.  its the kind of tool that would come in real handy occasionally, but not often enough to justify shelling out hundreds of dollars.  Wanting one anyway, I set out to make my own.  it turned out to be not only an exciting project, but a true adventure of discovery as it provided a window into the workings of lock-in amplifiers __ Designed by Dick Cappels

Low Capacitance Scope Probe Adapter -  An adapter to allow low capacitance probing of high frequency circuits.   __ Designed by Dick Cappels

Low cost video Motion Detection -  This device uses a PIC 16F819 and an LM339 to detect motion on a video signal.  The incoming video is 'clamped' using one section of the LM339, the sync tips are detected with another section, and a 3rd section can detect VBi or other data.   __ Designed by Luhan Monat-Mesa Arizona

Low-Cost Dusk-Dawn Controller -  This dusk-dawn controller is built around a light-dependent resistor among other components.  The common battery supply is used for operating the circuit as well as for load, that is, for power LED/small inverter circuit.  Resistors work as voltage divider and current limiter in the circuit.  LEDs are used as circuit deactivation indicator.  An n-channel MOSFET is used for the switching action of an LED light.__ Electronics Projects for You

Low-Cost LPG Leakage Detector -  The circuit for an LPG leakage detector is readily available in the market, but it is extremely expensive and usually based on a microcontroller (MCU).  This project presents a low-cost circuit for an LPG detector that you can build easily.  The main objective of the circuit is to detect LPG leakage anywhere. At the heart of the circuit is dual comparator IC LM393 (IC 2).  it is used to compare two different voltages, in this case reference voltage and MQ-6 gas sensor output voltage__ Electronics Projects for You

LTD-Low Cost Telemetering Device -  The ATmega8 microcontroller-based Low-Cost Telemetry Device (LTD) is an efficient telemetry keyer.  The LTD measures the voltage levels of up to four analog channels via its on-chip 10-bit ADC, converts the measurements to numbers, and then sends the data in Morse code to an external transmitter and to an attached RS-232 terminal.  it can be set up either by the RS-232 terminal, in which case, a character string, such as transmitter iD, can can be sent, or it can be set up with only jumpers to ground.  Parts count is very low, in part because the ATMega8's internal clock is used for timing.  Jeff Heidbrier came up with the idea for this project, built the prototype, and colaborated with me on the design of the LTD and this documentation. 
 __ Designed by Dick Cappels

Mag Card Reader -  The unit provides the magnetic head on a spring mechanism along with low level head signal amplifiers and data slicers.  Three signal lines coming from the unit provide card presence, clock, and data.  When actively reading a card, it draws about 50ma of current at 5 volts.   __ Designed by Luhan Monat - Mesa Arizona

Magnet Kicker -  Magnet Kicker keeps any magnet in motion to make simple motors or "perpetual motion" toys.   __ Designed by Nyle Steiner K7NS

Magnetic Card Reader -  The unit provides the magnetic head on a spring mechanism along with low level head signal amplifiers and data slicers.  Three signal lines coming from the unit provide card presence, clock, and data.  When actively reading a card, it draws about 50ma of current at 5 volts.   __ Designed by Luhan Monat - Mesa Arizona

Make a Bridge Rectifier from Diodes -  Make your own single or multi phase bridge rectifier from diodes.   __ Designed by REUK-Renewable Energy UK website

Make a Potato Battery -  The basic experiment is based on the use of a potato, but many fruits and vegetables work as potential batteries!  For the zinc electrode, a large galvanized nail works well.  Nails with a thick, rough zinc texture are preferable to galvanized nails that are smooth __ Designed by EETech Media, LLC.

Make a Quick-Turnaround PCB for RF Parts -  12/15/10 EDN Design Ideas:  Parts get smaller, but the laws of physics don't change.  Your designs must change to compensate.  [Design ideas by Steve Hageman, AnalogHome.com, Windsor, CA __ Circuit Design by Steve Hageman, AnalogHome/com, Windsor, CA

Make a Shunt Resistor -  Make your own rough and ready shunt resistor.   __ Designed by REUK-Renewable Energy UK website

Make a Simple Circuit Battery Status Monitor -  Monitor battery status with this easy electric circuit project - no skill required! .   __ Designed by REUK-Renewable Energy UK website

Make your own light bulb -  an amazing article on making your own light bulb.  The project is quick and simple, but a little pricey __ Designed by Theodore Gray, co-founder of Wolfram Research, Inc makers of Mathematica

Make your own multimeter -  The most important and expensive component in a meter is the movement: the actual needle-and-scale mechanism whose task it is to translate an electrical current into mechanical displacement where it may be visually interpreted.  The ideal meter movement is physically large (for ease of viewing) and as sensitive as possible (requires minimal current to produce full-scale deflection of the needle __ Designed by EETech Media, LLC.

Making Voltage Doublers & Multipliers -  Find out how to construct an AC voltage doubler circuit.  Extend it to a tripler circuit and more.   __ Designed by REUK-Renewable Energy UK website

MarshmalLow Bazooka -  This device uses a PIC 12F615 to implement a capacitor discharge ignition system.  When the switch (button) is closed, the PIC  sends pulses to the iRF644 MOSFET creating high voltage pulses to charge the 1.0 uf/250 volt capacitor.   __ Designed by Luhan Monat-Mesa Arizona

MAX038 Function/Sweep Generator with Markers ATtiny2313, AT90S1200A -  Maxim's MAX038 function generator chip is capable of producing nearly constant amplitude sine, square, and triangle waves with a low output impedance, from a very low frequency to more than 20 MHz.  Basically, a function generator on a chip.  Here is a function/sweep generator that uses the MAX038 chip.  The design described on these pages are not so much instructions for duplicating the design as they are a collection of ideas to stimulate your own thoughts __ Designed by Dick Cappels

Max-038 Signal -  The Max-80 function gernerator IC is specified to work to 20 MHz.  So far, this unit works nicely to 50KHz.  Since I seldom need signals higher than that, it has taken up a happy.)  __ Designed by Luhan Monat - Mesa Arizona

MAX187 ADC Project -  interfacing the MAX187 12 bit ADC to the BSii or BS1 to measure analog voltages.  The MAX187 requires an SPi interface (3 i/O's) to communicate with the stamp, and only requires a few external components.   __ Designed by Shaun Wilson

Memory Card Reader -  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

Methanol engine 10cc Mounted on a small light scooter -  A real Psycho project __ Designed by Thomas Scherrer OZ2CPU

Microscopic Views of a Printed Board -  Photographs of homemade circuit boards under 10x, 60x, and 200x magnification using the intel QX3+ microscope.  Shows details of pixel aliasing, copper cracks, poor resist transfer, and soiling from sticky flux paste.   __ Contact David Cook

Minilogger V1.0 -  Build your own a personal data logger for recording analog signal.  The MiniLOGGER provides 8-channel analog input (-99mV to +999mV) ,  __ Designed by Wichit Sirichote

Minimum Mass Waveform Capture & Display -  The result was a project that includes a waveform capture circuit, a graphic LCD (Liquid Crystal Display) and a control panel with LED indicators.  The details of the Graphic LCD display unit, composed of the LCD module, a serial interface, and bias supply were published earlier on this site,  __ Designed by Dick Cappels

Minimum Mass Wireless Data Coupler -  Bidirectional RF communications works like very short range (10 to 15 cm) radio but is as easy as iR.   __ Designed by Dick Cappels

Mini-Sumo Robot Ring -  A mini-Sumo ring is small, lightweight, and can be transported in a car.  Having your own personal ring gives your robots the advantage of plenty of practice and experimentation.  it's easy to build a competition-quality ring when you know the tricks.   __ Contact David Cook

MK-484 Receiver Chip Evaluation Board for AM & Lowfer bands. -  The basic MK484 (Replacement for the ZN414) connected in its minimum configuration as a radio receiver for the A.  M.  Broadcast band the upper half of the United States' FCC Part 15 Lowfer (1600-1750 meter) band __ Designed by Dick Cappels

MkI Video Digitizer -  This frame grabber design digitises pictures to very high quality in monochrome (8-bit black & white). Although designed for the European standard 625-line / 50Hz TV system, it should work with the American 525-line / 60Hz standard with minimal modification. __ Designed by W.A. Steer  PhD

MkII Video Digitizer -  A "video-digitiser" (also known as a "frame grabber") captures television pictures from a TV set, camera, or video recorder, etc., and forwards them to a computer for display, storage, or general manipulation. This document describes a home-built digitiser which interfaces to an EPP (or bi-directional) parallel port on iBM PCs. __ Designed by W.A. Steer  PhD

Morse Beacon -  The Morse beacon can be programmed with a short sentence or phrase, which is then retained in non-volatile memory and subsequently keyed out automatically in a repeating fashion as might be done to advertise a callsign, etc.   __ Contact Karen's Microprocessor Projects

Morse Code Alarm Clock Modification -  (Almost) Trivial application of an AT90S2313 or ATtiny2313 in an alarm clock to change the alarm from "BEEP BEEP BEEP BEEP BEEP BEEP BEEP BEEP" to "WAKE UP" in Morse code.  This was designed in response to a request and is in daily use __ Designed by Dick Cappels

MP3 Player -  These schematics are one of three parts needed to build the entire MP3 player. The other two are the 8051 Development Board and iDE interface.__ 

MP3 Player (Rev C) -  Student Project Alert: Many students request this schematic. Many student projects have a scope of work where using this design is legitimate, like this student project where they tried to write ATAPi drivers. For student projects which mandate original hardware design work (not just construction or modification of an existing design) , using this large and complex design would be very unwise, as it is more sophisticated than a typical student project.__ 

Multi NiCad Charger -  This unit was constructed in the shell of a Radio Shack battery charger.  The original unit charged only one type of battery at a time and only in pairs.  This unit allows for mix and match for AAA, AA, C, and D cells.  Each battery is individually monitored and charged.  An LED for each one flashes to show the current charging condition as follows __ Designed by Luhan Monat - Mesa Arizona

Multiple output power supply test system -  Most OEM's realize the value of being able to test at the subsystem level, but most don't realize just how cheaply and fast a small dedicated power supply tester can be built - so they don't even try.  in the critical start-up phase of any major project launch, when all the various parts are __ Designed by Steve Hageman


Electronic Construction Projects: 
#'s - B         C - D         E - G        H - K         L - P         Q - S         T - Z

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