Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
Analog to Digital
Data Bus Circuits
Voltage to Pulse
Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
Voltage to Current
voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
DIY HV Variable Cap
DIY PMA alternator
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Arduino Projects and Circuits
Arduino Projects and Circuits
RFID security access project using Arduino Uno
This project is influenced by the effort to achieve a security system that can be used in the business, or even very simply at the door of your home. This security system uses the microcontroller of the Arduino Uno system in combination with RFID (radio frequency identification) technology. It gives you the possibility of a wireless...
Arduino DAC Signal Generator project
Once the circuit gets current, all variables are initialized and the loop function is continually running. Initially all LEDs are off and there is no signal at the output. By pressing the signal switch, the first light that shows the most signal is at the output and the D0-D7 terminals give the appropriate signal which, when passing from the...
MIDI Output with Arduino
This page covers only the details of MIDI communication on the Arduino module. For a more general introduction to MIDI on a microprocessor, see the MIDI notes on Tom's physical computing site. MIDI, the Musical Instrument Digital Interface, is a useful protocol for controlling synthesizers, sequencers, and other musical devices. MIDI devices are...
Arduino-based AVR High Voltage Programmer
Fortunately, my trusty Arduino came to the rescue I created an Arduino-based AVR programmer that uses the high voltage programming mode and can fix pesky fuses like RSTDISBL. The Arduino has just enough IO to implement the entire HV protocol plus a go” button. So far I have only implemented setting LFUSE and HFUSE in software, but there is no...
Arduino Day-Night Controller
The Circuit is composed of two sections, the light sensing and the power switching. The light sensing part consists of a photo-resistor R4, connected like a voltage divider to R2. Since the resistance of the photo-resistor changes depending on the amount of light that is shining on it, the voltage divider's voltage ratio changes depending on the...
Guitar Effects / Pedal with arduino
Make your own Guitar Effects Pedal with an Arduino board. Bit crushing, rate reducing, weird noises. 10-bit effects/guitar pedal with an Arduino for lo-fi DSP
Guitar Loop with Arduino
Build a Guitar Looper with an Arduino board. Here is how to produce pedalboard for electric guitar. The idea is to connect pedals to the Arduino, and to use them to control a software of sound processing in Pure Data. Here I show you the example of a looper, but one can be also made a rack of effects without problem.
Arduino Punk Console
A programmable 8 step tone sequencer using an Arduino microcontroller. Features a 2 line x 16 character backlit LCD display
Control the speed of a DC motor with a potentiometer with an Arduino board
A quick circuit showing how to control the speed of a DC motor with a potentiometer with your Arduino board. Also shows how to use a TIP120 transistor to allow the Arduino control a larger power supply.
Arduino Guitar Delay Pedal
An attempt at an Arduino guitar pedal. The guitar signal feeds through a PT2399 delay circuit, modified to include a JFET preamp phase. The delay circuit has Echo and Delay knobs. From there, it feeds into an optoisolated-Arduino-5V preamp, and out to the Arduino. The output from the Arduino is filtered and sent to the amp.
Programming Arduino Wirelessly
The Arduino system offers an easy and open-source method for programming microcontrollers. Normally this means using a serial cable or USB cable attached directly to the microcontroller project. But what if your project is floating in a weather balloon, glued to the bottom of a swimming pool or baked into a loaf of bread It would be great to uplo
Arduino Retro Computer with SD card and LCD
Added a BASIC preprocessor made in python that allows you to write code withought line numbers and to use labels. the preprocessor adds the lines and changes the labels to line numbers. Also made an AmericanFootball BASIC game, as an example of how to use the preprocessor. Also made some small changes to the firmware, so make sure to update that t
Arduino Make your own hardware
The world is going nuts over the Raspberry Pi single-board computer (SBC) for being a whole system under $50. In reality though the Pi isn`t actually the cheapest computing device available. If you want really cheap how does $13. 50 sound for a mini computer that can plug into your PC`s USB port be programmed in C+ and let loose into the real worl
arduino masterclass part 2 build an led weather station
Arduino TV weather channel
So far the idea has been to show you how the Arduino Uno board and its Atmel ATMEGA328P microcontroller can interact fairly simply with the outside world. This time we`re simplifying the electronics but ratcheting up the demands on the microcontroller by aiming to hook up our Arduino Uno to the most complicated display output option available: tel
Arduino Digital audio player
So far in this series we`ve had a diverse look at how Arduino can interact with a range of real-world devices from servo motors to ultrasonic range finders TVs to humidity sensors. Now we`ll see if we could get the Arduino to make a few sounds. We`ll actually do a bit better than that we`ll look at the importance of pulse width modulation (PWM
Arduino How to control a Servo
In this one, servo is programmed to be controlled by two buttons, one turns servo to the left and the other one turns it to the right. When the servo is turning, corresponding LED will be switched on to indicate the operation. Because Arduino has built-in library for controlling servo, which makes servo a really easy kit to use. In this project,
Arduino Project RomG
Arduino GSM Shield
The Arduino GSM Shield connects your Arduino to the internet using the GPRS wireless network. Just plug this module onto your Arduino board, plug in a SIM card from an operator offering GPRS coverage and follow a few simple instructions to start controlling your world through the internet. You can also make/receive voice calls (you will need an ex
Arduino Stepper Unipolar Circuit
The text of the Arduino reference is licensed under a Creative Commons Attribution-ShareAlike 3. 0 License. Code samples in the reference are released into the public domain.
Arduino Analog Input
A potentiometer is a simple knob that provides a variable resistance, which you can read into the Arduino board as an analog value. In this example, you`ll connect a poterntiometer to one of the Arduino`s analog inputs to control the rate at which the built-in LED on pin 13 blinks. Connect three wires to the Arduino board. The first goes to ground
Arduino Analog WriteMega
Connect the longer, positive legs of (anodes) 12 LEDs to digital pins 2-13 through 220 ohm current limiting resistors. Connect the shorter, negative legs (cathodes) to ground. moves through each of the LEDS one by one, from the lowest pin to the highest. Before this loop is allowed to move from one pin to the next, two things must be accomplished.
The bar graph - a series of LEDs in a line, such as you see on an audio display - is a common hardware display for analog sensors. It`s made up of a series of LEDs in a row, an analog input like a potentiometer, and a little code in between. You can buy multi-LED bar graph displays fairly cheaply, like this one. This tutorial demonstrates how to
Arduino Barometric Pressure WebServer
This example shows how to use SPI communications to read data from a SCP1000 Barometric Pressure sensor, and how to then post that data to the web by using your Arduino/Ethernet Shield combo as a simple web server. Using the Ethernet library, your device will be able to answer HTTP requests by responding with just enough HTML for a browser to dis
This example demonstrates one techinque for calibrating sensor input. The Arduino takes sensor readings for five seconds during the startup, and tracks the highest and lowest values it gets. These sensor readings during the first five seconds of the sketch execution define the minimum and maximum of expected values for the readings taken during th
A piezo is an electronic device that generates a voltage when it`s physically deformed by a vibration, sound wave, or mechanical strain. Similarly, when you put a voltage across a piezo, it vibrates and creates a tone. Piezos can be used both to play tones and to detect tones. The sketch reads the piezos output using the analogRead() command, enco
Arduino Liquid Crystal Cursor
The Liquid Crystal Library allows you to control LCD displays that are compatible with the Hitachi HD44780 driver. There are many of them out there, and you can usually tell them by the 16-pin interface. Before wiring the LCD screen to your Arduino we suggest to solder a pin header strip to the 14 (or 16) pin count connector of the LCD screen, as
Arduino Master Reader
In some situations, it can be helpful to set up two (or more!) Arduino boards to share information with each other. In this example, two Arduinos are programmed to communicate with one another in a Master Reader/Slave Sender configuration via the I2C synchronous serial protocol. Several functions of Arduino`s Wire Library are used to accomplish t
MIDI, the Musical Instrument Digital Interface, is a useful protocol for controlling synthesizers, sequencers, and other musical devices. MIDI devices are generally grouped in to two broad classes: controllers (i. e. devices that generate MIDI signals based on human actions) and synthesizers (including samplers, sequencers, and so forth). The latt
Arduino Motor Knob
Stepper motors, due to their unique design, can be controlled to a high degree of accuracy without any feedback mechanisms. The shaft of a stepper, mounted with a series of magnets, is controlled by a series of electromagnetic coils that are charged positively and negatively in a specific sequence, precisely moving it forward or backward in small
The Ping is an ultrasonic range finder from Parallax. It detects the distance of the closest object in front of the sensor (from 2 cm up to 3m). It works by sending out a burst of ultrasound and listening for the echo when it bounces off of an object. The Arduino board sends a short pulse to trigger the detection, then listens for a pulse on the s
Arduino SFR Ranger Reader
This example shows how to read a Devantech SRFxx, an ultra-sonic range finder which communicates via the I2C synchronous serial protocol, using Arduino`s Wire Library. The I2C protocol involves using two wires to send and receive data: a serial clock pin (SCL) that the Arduino pulses at a regular interval, and a serial data pin (SDA) over which
PIC Microcontroller Circuits
AVR Microcontroller Circuits
Microcontroller Programmer Circuits
68HC11 Microcontroller Circuits
8051 / 8052 Microcontroller Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity