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

Negative Resistance Code Practice Oscillator -  A simple home made negative resistance audio code practice oscillator that also makes experimenting with negative resistance materials fun and easy without having to use an oscilloscope or curve tracer.   __ Designed by Nyle Steiner K7NS

Negative Resistance Oscillator with Homemade Tunnel Diode -  This project may not be very practical but I find it to be a very exciting experience.  When I first heard about tunnel diodes many years ago, they seemed to me, to be one of the most exotic devices on earth.  it was very exciting to discover that I could easily make at home, at least in very crude form, an actual working device that is similar__ 

Network Car Controller -  PIC  Project  Our present car controller runs on a single PIC 16F870 micro and provides functions for remote door locks, headlight reminder, and car finder.  it is constructed using wire-wrap to allow for future expansion and is mounted using Velcro on the passenger side of the center console __ Designed by Luhan Monat-Mesa Arizona

NiCad Charger -  Sometimes its more convenient to recharge batteries 'in place' rather than removing them and putting them in an external charger.  This device is built around a PIC 12F675 (a dandy little part from Microchip).  The number of cells (1 to 8) is programmed in using the one button __ Designed by Luhan Monat - Mesa Arizona

On and Off Programmable Controller for 3-Phase Motor -  Automatic on/off controller for a 3-phase electric motor can be made with a programmable time switch.  in this case a maximum of eight time durations can be programmed.  The system has two...__ Electronics Projects for You

Oxygen Sensors -  When they go bad your automobile runs poorly, learn about them and build a substitute for diagnostics or off-road use.   __ Designed by Bob Blick

PC Controlled Relays -  A popular design with dozens of applications.  The design is simple and compact.  Switch almost everything on and off with a simple mouse click.  Some tech specs: relay outputs, on-board power regulator, on-board serial port.   __ Designed by Projects & Ideas from Nutchip.com

PC-Based GPS Receiver -  Today, there are many gadgets available with GPS technology.  GPS stands for ‘global positioning system.’ it provides the data corresponding to the position of the GPS receiver itself on international-standard latitude-longitude...__ Electronics Projects for You

Permenant Magnet Levitation -  Magnetic levitation using permanent magnets.  No superconductors, no energy input for stabilization and no spinning tops.  Earnshaw - take a hike.   __ Designed by Nyle Steiner K7NS

Phone Intercepter 1 -  PIC  Project  This device connects between the phone line, an answering machine, and your phones.  When a phone call comes in, the answering machine picks up the call and informs the caller to enter the access code to ring the phone or to wait for the beep and leave a message.  if the correct code is entered, the answering machine is immediately disconnected while the device generates phone ringing tones on an external speaker.  Picking up any phone causes the device to return to its initial state.   __ Designed by Luhan Monat - Mesa Arizona

Phone Interceptor 2 -  PIC  Project  This unit is an upgrade of the previous phone call interceptor.  instead of using an answering machine to provide the outgoing message and recording functions, it uses the iSD4004 (from Windbond Electronics).  The iSD4004 records up to 8 minutes of audio.  I use the first several seconds for outgoing message prompts.  The remaining time is used to record up to 30 messages, depending on message length.   __ Designed by Luhan Monat - Mesa Arizona

Phone Line Box -  This is an educational site of PIC  Projects in various stages of development along with pictures, source files, object code files, schematics, and board layouts.  You are welcome to use what you like at your own risk.   __ Designed by Luhan Monat - Mesa Arizona

Phone Messager -  i always keep one totally self powered phone (the way they all used to work) in case of a power failure.  This device works the same way, taking all of its power directly from the phone line. __ Designed by Luhan Monat - Mesa Arizona

Photocell, but Intelligent -  This photocell shows how to use the Nutchip analog comparator input.  The project is shown first in a laboratory version, ideal for experimenting with a breadboard.  A second more improved version is also shown, showing the tricks used by the pro's in order to make the circuit more reliable.   __ Designed by Projects & Ideas from Nutchip.com

PIC (with source cord) 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).   __ Designed by Luhan Monat-Mesa Arizona

PIC Based WWVB Decoder -  With an analog input, this circuit will decode and display the WWVB time code. __ Designed by Steve Hagerman

PIC DAS - A PIC / PC Based Data Acquisition System -  Control anything with your PC!  (Featured in QEX)  __ Designed by Steve Hagerman

PIC Desktop Thermometer -  A very simple desktop thermometer using a PIC  and two seven segment displays __ Designed by Steve Hagerman

PIC Development Article -  Some methods that I use to develop PIC  Projects on a shoestring. (Featured in QST)  __ Designed by Steve Hagerman

PIC Meeting Minder -  A tool to keep meetings on time!  __ Designed by Steve Hagerman

PIC Micro Programmer-MAC, Win98, XP, Vista, DOS, Linux, etc -  This programmer requires only a basic terminal program capable of uploading an acsii PIC  HEX file.  it does not matter what operating system or computer (MAC, Win98, XP, Vista, DOS, Linux, etc.) is used to talk to it.   __ Designed by Luhan Monat - Mesa Arizona

PIC NiCad Battery Charger -  This cheap and easy to build NIC d/NiMH
Battery Charger is suitable for automatically charging a wide range of batteries for many applications.  Proper chargers are usually expensive and cheap chargers supplied with the original equipment often incorrectly charge the cells and dramatically shorten their life __ Designed by Peter Hayles

Pin Diode Based Fire Sensor -  This is an ultra-sensitive fire sensor that activates an alarm when it detects fire.  in this circuit, a sensitive PIN diode is used as a fire sensor for longer-range fire detection.  it detects visible light and infrared (iR) in the range of 430 nm – 1100 nm.  Visible light and iR from the fire activate the sensor to trigger the alarm.  it also detects sparks in the mains wiring and if these persist, it gives a warning alarm.  The anode can easily be identified from the top-view flat surface of the photodiode.  A small solder point to which a thin wire is connected is the anode and the other one is the cathode terminal.__ Electronics Projects for You

Plant Minder -  PIC  Project  The PIC 12F615 was perfect for this project.  it runs off a 3 volt lithium cell.  The unit is self calibrating.  Just wait until your plant needs watering, insert the battery, and place in the soil.  This sets the threshold for sensing dry soil.  When the soil dries out to this point, the unit begins 'chirping' about every 20 minutes.   __ Designed by Luhan Monat - Mesa Arizona

Plus-Minus 5V Supply From 9V Battery -  Op-amps require dual-polarity supply for proper operation.  When working with battery supply, it becomes difficult to get dual power supply for the op-amps.  Presented here is a simple circuit that provides ±5V from a 9V battery.  This is one of the interesting projects among Electrical Engineering Project ideas.  Op-amps require dual-polarity supply for proper operation.  When working with battery supply, it becomes difficult to get dual power supply for the op-amps.__ Electronics Projects for You

Postman Buddy + Wireless Doorbell -  Go beyond wireless doorbells: a mini-central that tells you when a letter is waiting you in the mailbox and if someone rung your bell when you were not at home.  Complete design including PCB.   __ Designed by Projects & Ideas from Nutchip.com

Power Bank for Smartphones -  This power bank can be used for charging smartphones.  The circuit uses two integrated modules and a lithium-ion battery.  The first module is a lithium-ion battery charger and the second is...__ Electronics Projects for You

Power Controller -  PIC  Project  This device controls the power to 8 individual outlets.  There are 16 power levels available for each one.  Connection is made via 9600 baud serial using a din-5 connector.  A single byte sets the power level for any of the 8 channels.  Also, a global command sets all the power levels at once.   __ Designed by Luhan Monat - Mesa Arizona

Power supply for a car tube Amplifier -  To minimize heat loss on any transistor, I use two pass FETs.  in the car, input voltage is either 11.5-12.5V (engine off) or 13.5-14.5V (engine on).  in the first case, T1 and T2 are fully ON, no need for heatsink.  in the second case - T1 is OFF, T2 ON, all voltage and power excess is released across R5, no heatsink necessary for FETs.  However, when input is in between (1314V) - T1, in a linear regulator mode, may dissipate up to 3W (for a 3A load current).   __ Contact Klausmobile Tube Tester Files

Preamp & 330 + MHz Prescaler -  A preamp that drives the CMOS counter input and a divide by 10 prescaler to extend the range __ Designed by Dick Cappels

PreAmplifier for Microphone or Guitar Use -  suitable for guitar or microphone use __ Designed by Bob Blick

Precision Portable Voltage Reference -  it has been said that a man with one watch knows what time it is, but a man with two watches is never sure.    The same can be said for a person who has more than one voltmeter.    in my situation, I have several voltmeters in each of two different locations a third of the way around the world apart.  The best solution would be to send the meters to  NiST traceable calibration labs,  __ Designed by Dick Cappels

Printed Board for Sandwich -  Stuffing instructions for a professional, double-sided, printed circuit board for Sandwich.  The board has silkscreened part numbers and a solder mask, making it a fast, easy, and reliable way to build.   __ Contact David Cook

Printer Sharing Switch -  i had two computers, a Mac Mini and a generic Windows computer.  Both were on different networks, but in the same room, and I wanted to share a Lexmark USB laser printer between the two of them.  I ended up making this switch to share the printer between the two computers __ Designed by Dick Cappels

Programmable 3 phase Controller for ON/OFF Motor -  Automatic on/off controller for a 3-phase electric motor can be made with a programmable time switch.  in this case a maximum of eight time durations can be programmed.  The system has two...__ Electronics Projects for You

Programming adaptor for 8 & 28 pin AVR Microcontrollers using ISP  -  Okits not pretty, but its practical.  The 20 pin connector at the far right is left over from a diffferent project and is no longer used.  This adaptor lets me program 8 or 20 pin DiP devices using the in-System Programmer (iSP) described in Atmel's AVR910 application note.  This circuit provides power and clocks for the part to be programmed and power to the iSP circuit.  When programming 8 pin devices, the part is positioned toward pins 1 and 20 of the socket such that the 8 pins of the chip occupy the pins 1, 2, 3, 4, 17, 18, 19, abd 20 of the programming socket.  in the case of an 8 pin part being programmed, the SPST switch that grounds pin 4 must to be closed.  Conversely, when programming a 20 pint part, the switch on pin 4 must be open so the crystal can be used for the clock for the part being programmed.   __ Designed by Dick Cappels

Propane Powered Lawnmower -  A simple and crude conversion of a lawnmower to run on propane.  Runs Great! ! .   __ Designed by Nyle Steiner K7NS

Propellor clock PIC16F84 -  A motor spins the "propeller", and a small microprocessor keeps track of time and changes the pattern on seven LEDs with exact timing to simulate a 7 by 30 array of LEDs.  it is an illusion, but it works nicely.   __ Designed by Bob Blick

Pulsed Linear Induction Motor -  The ultimate objective is to build a six-stage launcher system with a total energy storage of about 150 joules.  This project is only the first stage (around 25 joules) for feasibility testing __ Designed by Barry Hansen

PWM Motor Control -  PIC  Project  This device acts as a variable speed control for the heater blower in a car.  it takes its power directly from the existing wiring and connects with just 2 wires.  it will also work for any 12 volt device up to 10 amps.   __ Designed by Luhan Monat - Mesa Arizona

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Electronic Construction Projects: 
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