Month: November 2022
-
Introduction
Resistors are color coded to indicate their resistive value. If you already know how to read the color code—or once you learn how—you’ll be able to glance at a resistor and tell automatically what its value is. But what about other components in your projects? What about the LEDs, potentiometers, buzzers, or even the wires…
-
Circuit Theory
The 2N3904 or S39013 NPN transistor amplifies or increases the audio signal created by the Arduino. The transistor has an amplification value called “gain” used to determine the volume of an electrical signal. A typical gain value engineers use in designing simple amplifiers like this one is 100. The mini 8Ω speaker can be wired…
-
Upload the Theremin Sketch
It’s time to upload the sketch to the Arduino with the Theremin’s photocell and simple transistor amplifier circuits built on the MakerShield. Example 12-1 operates the Arduino-based Theremin using a photocell and a simple transistor amplifier circuit. Here are the steps you’ll need to follow: Once the Theremin sketch has been uploaded to the Arduino, the mini 8Ω…
-
Let’s Build a Theremin
The Theremin, invented in 1920 by Russian inventor Leon Theremin, uses an electronic circuit called an oscillator to create different sounds. In our Theremin, we’re using the Arduino as an oscillator by programming it to select different tones based on changing light levels. The tone changes are made by waving your hand over a photocell, creating various…
-
Introduction
A Simple Transistor Amplifier Electronic circuits that produce audible sounds have been used to create strange and eerie audio effects for science-fiction movies like Star Wars and Marvel’s The Avengers. The Theremin is a device that generates different electronic sounds by waving hands over and around a pair of protruding antennas. You can make your own awesome Theremin using…