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Create Your Own Stylus-Controlled Synthesizer

Create Your Own Stylus-Controlled Synthesizer

In this project article, we'll use a 555 timer IC to build an iconic musical instrument from the early days of synthesizers.


Building a Resistor Color Code Calculator and Ohmmeter Using Arduino

Building a Resistor Color Code Calculator and Ohmmeter Using Arduino

For this project, I built a handheld resistor color code calculator and ohmmeter using the ATmega328 microcontroller and a 1.8-inch color LCD display.


A Cortex-M Microcontroller-Enabled Electronic Timer: A Radio Shack Remix

A Cortex-M Microcontroller-Enabled Electronic Timer: A Radio Shack Remix

In this Radio Shack Classic Circuits Remix, we add modern microcontroller functionality to the vintage Electronic Timer project for the Science Fair 65-in-1 kit.


Projects Sep 15, 2024 by Don Wilcher
Using Clever Techniques to Convert a Passive Audio Filter Into an Active Filter

Using Clever Techniques to Convert a Passive Audio Filter Into an Active Filter

This project covers two fascinating and useful circuit design techniques—the Burton Transform and Dualling—that allow us to transform a passive network into an active network while building an audio noise filter.


Projects Jun 02, 2024 by John Woodgate
Designing a Wideband Analog Voltage and Current Meter

Designing a Wideband Analog Voltage and Current Meter

Design a wideband analog multimeter to measure AC voltages and currents from 20 Hz to 1 MHz with a selectable sensitivity from 1 mV to 100 V, while the ammeter has a selectable current sensitivity of 10 mA to 10 A.


Projects May 03, 2023 by John Woodgate
Construction of a Guitar Amplifier

Construction of a Guitar Amplifier

This article explains the theory and the construction of the circuit of a 10W practice guitar amplifier.


How to Build a Class-D Power Amp

How to Build a Class-D Power Amp

Learn how to build your own Class D power amplifier—one of the most efficient ways to listen to music.


Projects Aug 29, 2018 by Cezar Chirila
Build Your Own Negative Voltage Generator

Build Your Own Negative Voltage Generator

Everyone needs a negative voltage rail eventually, but most only have a single rail supply. This project will show you how to build a negative voltage generator that runs off a single rail supply!


Projects Jun 07, 2018 by Robin Mitchell
Save for Your Own Royal Wedding (of Sorts) with the Gentleman Maker’s Savings Incentivizer

Save for Your Own Royal Wedding (of Sorts) with the Gentleman Maker’s Savings Incentivizer

In this project, we'll use a Raspberry Pi to create a responsive piggy bank that belittles you when you slack on your savings!


Projects May 10, 2018 by Robin Mitchell
Incorporating Microphone Functionality into a Robot System

Incorporating Microphone Functionality into a Robot System

In this article, we’ll look at a fairly straightforward circuit that enables a robot or other device to detect sound.


Projects Sep 11, 2017 by Robert Keim
Mitigate Power Failure Programming Issues Using EERAM

Mitigate Power Failure Programming Issues Using EERAM

In this how-to article, we explore the use of I2C EERAM to save critical program variables when power fails and restore them when power returns to easily preserve program continuity.


Learn About ATmega328P Fuse Bits and How to Use Them with an External Crystal Oscillator

Learn About ATmega328P Fuse Bits and How to Use Them with an External Crystal Oscillator

This project introduces ATmega328P fuse bits and shows how to set them to use an external 16 MHz crystal oscillator.


The Holiday Season Analog Alarm! A Gift-Defending System

The Holiday Season Analog Alarm! A Gift-Defending System

Nowhere to hide presents this holiday season? No problem! This alarm will sound anytime a loved one tries to get a sneak peek at his or her surprise.


Projects Dec 05, 2016 by Ryan Jones
Raspberry Pi Object Detection Cat Toy

Raspberry Pi Object Detection Cat Toy

This object detection toy will keep your cat's head spinning for hours!


Projects Nov 07, 2016 by Ryan Jones
Build Your Own LED Saber—Audio and Power Systems

Build Your Own LED Saber—Audio and Power Systems

In part 2 of the LED saber project, we'll assemble the power and audio systems.


Projects Oct 19, 2016 by Jeremy Lee
Build Your Own Metal Detector with an Arduino

Build Your Own Metal Detector with an Arduino

Building a metal detector using a Colpitts oscillator and an Arduino.


Projects Oct 03, 2016 by Evan Kale
Build an Arduino BLE-Enabled Indoor Air Quality Monitor

Build an Arduino BLE-Enabled Indoor Air Quality Monitor

Use an Arduino/Genuino 101 with iAQ-Core air quality and HIH-6131 temperature/humidity sensors to make an Indoor Air Quality Monitor with Bluetooth low energy (BLE) connectivity.


Measuring Temperature with an NTC Thermistor

Measuring Temperature with an NTC Thermistor

For this article, we are only concerned with one type of sensor that can measure temperature. This sensor is called a thermistor.


Projects Aug 15, 2016 by Joseph Corleto
DIY Synth Series Part 1 — The Exponential VCO

DIY Synth Series Part 1 — The Exponential VCO

Build a 1V octave voltage-controlled oscillator (VCO) module and create your own analogue synth sounds.


Projects Aug 08, 2016 by Robin Mitchell
How to Build an Arduino-Controlled AM/FM/SW Radio

How to Build an Arduino-Controlled AM/FM/SW Radio

Combine the Si4844-A10 analog-tuned radio receiver with an Arduino to make a full-featured multiband radio.