Learn more about PWM in this in depth discussion.
Michael Kleinigger writes:
Pulse-width modulation. It probably sounds a little confusing if you’re new to electronics. Kindof a word mashup, really. What do pulses, width, and modulation have to do with each other anyway? I remember first learning about PWM during my freshman year of college at RPI. I was in a pilot course called “Foundations of Engineering” under the excellent instruction of Professor Kevin Craig (whom I later worked for). I remember thinking later, “Hey, this PWM stuff is pretty clever!” So let’s take a look at PWM and see what we can learn.
Discussing Pulse-Width Modulation - [Link]
Mike Martell writes:
While transistors have many uses, one of the less known uses by amateurs is the ability for bipolar transistors to turn things on and off. While there are limitations as to what we can switch on and off, transistor switches offer lower cost and substantial reliability over conventional mechanical relays. In this article, we will review the basic principles for transistor switches using common bipolar transistors.
Using Bipolar Transistors As Switches – [Link]
How to use an N channel MOSFET to turn anything on and off – [Link]
In the youtube video and article below learn how to use an oscilloscope and function generator
How to use an oscilloscope and function generator - [Link]
A bipolar transistor is a semiconductor device used to amplify or switch an electrical signal. On the youtube video above learn how a bipolar transistor is made and how it works.
How Transistors Work - [Link]
Transistors are electric switches that control current passes throught them. They come in many sizes and ratings depending on the current they can handle. In the article below learn how to connect a transistor to control a load such as a motor or lamp. The article is demostrating how to use high current transistor TIP120 with arduino.
Using a transistor to control high current loads - [Link]
Matt shares this comprehensive electronics tutorial site Learning Objects for Electronics. [via]
This is a site developed by my good friend Pat Hoppe and his colleagues at Gateway Technical College in Racine, WI. He made these flash animations to help his students practice the basics of electronics; Everything from units, resistor color code, logic gates, filters, op amps, transistors, and even how to use your Ti-86. As a HS electronics teacher, I am very grateful to Pat for the hours he spent mentoring me, and I use this site quite regularly with my students. He’s a great man, and this is a great site for our Make: comrades. Enjoy!
Learning Objects for Electronics - [Link]
MAKE presents: Ohm’s Law
Voltage, Current, and Resistance – three of the most important electrical properties, are elegantly intertwined by way of a simple equation; V = IR, better known as Ohm’s Law. Get to know this fundamental tool of electronics engineering – you’ll be glad you did! [via]
Here is a cool java applet written to help find valid values for 5% and 10% tolerance resistors. Quick clicks to common values and a clickable table of standard values in included. The tool even shows you the resistor code to make ordering parts easier.
Online Resistor Color Code Tool - [Link]