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Last Updated: December 31, 2017 06:44 AM

Capacitance Proximity Switch
Draws very low power - Ideal for battery-powered applications
6 Models Available - Call 806-368-7747

Links to electronic circuits, electronic schematics, designs for engineers, hobbyists, students & inventors:

Hack of Egyption Talking Frog Box -  This device 'listens' to a conversations and then interjects words and phrases at inappropriate times.   __ Designed by Luhan Monat-Mesa Arizona

Hack of Talking Fish using a PIC16F819 microcontroller -  These items were sold nationally several years ago.  The fish would sing, open its mouth, turn its head, and flap its tail.  After removing the back panel, all of the existing electronics were removed leaving only the 3 servo motors, speaker and photocell)  __ Designed by Luhan Monat - Mesa Arizona

Hack-Toy Car -  This car measures just 5 1/2 inches in length.  it was sold as a remote control car for $19.95 at Fry's Electronics here in Phoenix.  Powered by 4 AAA batteries, it has a small dc motor and a very interesting steering mechanism. (08/08/08)  __ Designed by Luhan Monat - Mesa Arizona

Half-flying capacitor analog multiplexer for microControllers -  This technique uses digital  i/O pins to multiplex analog voltages into an analog input on the microcontroller.  The method is most suitable for signals that do not need to be sampled frequently and it may be extended to accommodate a large number of inputs, though for a large number of inputs, the use of a separate analog multiplexer or a mincrocontroller with an integrated multiplexer would often be a better choice   __ Designed by Dick Cappels

Hard Drive Clock -  Have an old hard drive that no longer works? As long as it still spins up chances are you could build a clock out of your old hard drive!  You will need some electronic knowledge, some common electronic components and a bit of patience.  The clock that is produced isnít exactly practical __ Designed by Alan Parekh

H-Bridge drives DC Motors -  This circuit drives small DC motors up to about 100 watts or 5 amps or 40 volts, whichever comes first.  Using bigger parts could make it more powerful.  Using a real H-bridge IC makes sense for this size of motor, but hobbyists love to do it themselves, and I thought it was about time to show a tested H-bridge motor driver that didn't use exotic parts __ Designed by Bob Blick

HeadBanger Headphone Amp Construction Kit -  After the euphoria over receiving my new Sony Minidisc bundle had partially subsided, I noticed that the portable unit, the MZ-E40, has a rather weak output.  Measurements showed that it can only manage 80mV rms output and only about 74dB SPL output from the phones.  This is when recording at average level with 8dB of headroom.  in contrast __ Designed by Stephen H. Lafferty

Heliax 6 Meter Filter construction article -  A comprehensive filter construction article using 1-5/8 inch hardline  __ Designed by Robert W. Meister WA1MIK

Hexbot Robot -  The HEXBOT is constructed from 12 (cheap) model airplane servos.  Each leg moves laterally on one servo and vertically on the other.  Conveniently, this type of servo runs on 5 volts.  These servos need only a specific width pulse to position it.  Once it arrives at its target location, it draws very little power (about 10 ma).  Power is provided)  __ Designed by Luhan Monat - Mesa Arizona

HF AC Millivoltmeter adapter -  intended for use past 200 kHz, this adapter changes HF AC voltages between 2 mv P-P and 200 mv P-P to the corresponding DC level with linearity of better  than 1 millivolt.  A on-board calibration signal aids in calibration prior to use.   __ Designed by Dick Cappels

HF/VHF/UHF Test Oscillator -  This test oscillator covers 16 MHz to 300 MHz in six bands, using varactor tuning.  it has a high level output to drive a frequency meter and two sine wave outputs, one of which is 50 Ohms. 
This article was published in Croatian in infoelektronika magazine in June, 2012 (cooperatively)  __ Designed by Dick Cappels

High-Impedance Audio Buffer with JFET -  The buffer circuit described here can be used to enhance the AC input impedance of audio amplifiers that are used with pickups in musical instruments.  Some signal sources for preamplifiers, passive pickups...__ Electronics Projects for You

High-Voltage Capacitors, build your own! -  As one who supplies parts to those who experiment with high voltage, I get a lot of letters and phone calls from frustrated builders that go like: "Can you supply an inexpensive xxx microfarad capacitor at a working voltage of YYY? My only source wants $249 for one.  "Sometimes, a high price is justified; other times, a seller has the only capacitors of a special value available, and will soak you for the maximum dollar __ Designed by Tony van Roon  VA3AVR

Home Automation System -  in this era of digital revolution, we are surrounded by smart devices that are capable of making decisions on their own without much human intervention.  Our home can also be made...__ Electronics Projects for You

Home Built Laser Projector -  Laser projector is one of the laser display equipments.  This project builds the closed-loop galvos mainly and aiming at professional grade.   __ Designed by The Electronic Lives Manufacturing-presented Chan

Home built plasma globe. mmmplasma -  i'll start off with the plasma globe driver.  it is a single transistor driven flyback transformer.  You can find all the information on the construction of such a driver on the FLYBACK page linked through my homepage.  This particular flyback transformer came from an old mac monitor (parts are probably the best use for mac stuff) that I found outside the chemistry building at the University of iowa.  The monitor was pretty old.  Old enough that the potted rectifier stuck __ Designed by Greg Miller

Home Control Computer -  i used to have this dream of a "computerized home" where a benevolent computer, on a piece of plywood on the wall in the basement somewhere, would oversee the lights and heating, turn on radio or TV when interesting shows come on, make voice announcements of important reminders and so on.  I would be able to control this wondrous machine with a remote control from anywhere in the house, or call it up on the telephone, or push buttons on a locally wired keypad or whatever __ Designed by Markus Wandel

Home Evacuated Vacuum Tube -  i have always wondered if a vacuum tube could operate with a degree of vacuum attainable by amateur means.  This is how I broke open a vacuum tube triode and operated it after pumping it down with a vacuum pump.   __ Designed by Nyle Steiner K7NS

Home Made PBX/PABX -  i've been facsinated with telecommunications from an early age.  When I was twelve or so I had an intercom system from which I could talk to most of the house from my corner of the kids' room.  it was made out of the amplifier from a record player, and miscellaneous parts from old TV sets.  When I was fourteen someone gave me a WW2 vintage shortwave receiver with a blown power supply.   __ Designed by Markus Wandel

Home made portable battery charger -  Using a car alternator and a small petrol motor, you can build a very handy portable charger__ 

Home Made Vacuum Diode -  The next step - an actual homemade vacuum tube diode.   __ Designed by Nyle Steiner K7NS

Home Made Vacuum Triode -  The next step - first attempt at making an actual homemade vacuum tube triode.   __ Designed by Nyle Steiner K7NS

Home Security -  PIC  Project  Creating a modular, networked, home control system was greatly simplified by using common 4-wire phone cable with stake-on connectors.  The cable feeds both power and network signals to the various modules.  Each module is made on a single sided circuit board with RJ-11 connectors (for the network/power) along with other connectors as needed.  This eliminates the need for placing power feeds (wall worts) for each of the modules.  The entire system runs on one power feed.   __ Designed by Luhan Monat - Mesa Arizona

Home Security Project -  The security system application and program offers a simple demonstration of the BASIC  Serial interface.  By adding only a few door and window switches, a transistor, a siren, (see schematic) and a few lines of BASIC  program (see program listing) the interface can become a multi-function security system.  Please note, however, that it is a "barebones" program.  it is left to the reader to fancy it up to their liking.  __ KD5ZUG

Home Theater -  PIC  Project  This unit is designed to interface: TV sound, videotape sound, and 5.1 dvd sound to a 4 channel home theater system.   __ Designed by Luhan Monat - Mesa Arizona

Homebrewed Stamp -  My Homebrewed stamp.  I ordered it from Peter Anderson, he supplies all the components neccessary to build it, but no pcb board.  I got a friend of mine to make me a pcb board for it, then I just solder everything on.  You can just use a breadboard instead of a pcb board, but the pcb board make a nice job of it.  it is nice because all the IC 's are in sockets, so if you want to write to the EEPROM thousand times a day, you can, just replace it when its life it up.  its a great product, if you want to find more info on the Homebrewed stamp go over to my links section and look for Peter Anderson's website.   __ Designed by Shaun Wilson

Homebuilt RS232 LCD Interface -  This controller board takes anything between +5Volt to +30 Volt power , (have it's own regulator).  __ 

Homebuilt Video Digitizer Mark I -  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

Homebuilt Video Digitizer Mark II -  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

Homemade Binaural MICs -  i used the plans from http://www. Arches.uga.edu/~tidmarsh/binmic.html.  i'm no electronics expert but can solder, and it was very easy.  if you want to build a battery box you'll probably want some fine gauge wire and a little piece of circuit board in addition to the components listed. __ Designed by Doug Brown

Homemade Copper Oxide Thermoelectric Generator -  Homemade Copper Oxide Thermoelectric Generator Can Light An LED.   __ Designed by Nyle Steiner K7NS

Homemade Easter Egg Anemometer -  in any wind generator installation, it's critical to be able to measure wind speed.  That gives you a baseline against which to measure your machine's performance, and anemometers respond much more quickly to changes in wind speed than do wind generators.  Commercial anemometers  __ Contact OtherPower.com

Homemade Magnetic Audio Amplifier -  Circuit + Notes __ Designed by Nyle Steiner K7NS

Homemade Memristor -  Circuit + Notes __ Designed by Nyle Steiner K7NS

Homemade Printed Board -  Making a custom printed circuit board (PCB) takes some setup time and supplies, but is well worth the repeatable, reliable results.  The example board is single-sided copper with through-hole components.  Two-sided and surface-mount circuit boards follow.   __ Contact David Cook

Homemade Thermistor & Pressure Sensor -  it is easy to make a thermistor, thermoelectric generator or pressure sensor by heating a piece of copper wire.   __ Designed by Nyle Steiner K7NS

Homemade Tunnel Diode & RF Oscillator -  it is incredibly easy to make a homemade device that behaves similar to a tunnel diode.  Using it, a simple rf oscillator was made which could be coaxed into running at 12 mhz.   __ Designed by Nyle Steiner K7NS

Homemade USB ,HID compatible, input Device -  The PIC 16c745 is an OTP (one time programmable) device.  You can program one yourself, but you need an programmer that can do it, and do it right on first try.  This is why I offer to sell preprogrammed 16c745 and the SMD resonator, because these are the parts people may have trouble finding.  __ 

Homemade wide range variable electrolytic capacitor & oscillator -  A simple homemade wide range variable electrolytic capacitor using baking soda can vary in capacitance in one continuous sweep over a 5000 to 1 range.  This capacitor can vary the frequency of a simple relaxation oscillator over a similar range.  Even the zinc negative resistance oscillator can be continuously swept over the entire audio range.   __ Designed by Nyle Steiner K7NS

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

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