Learn About AC Theory!

...after you learn about DC circuits, you need to tackle AC Theory

Welcome. This site is here to help you learn about AC Theory. Our aim is to explain electronics simply, step by step, with the minimum of mathematics and using real components as our examples. You'll find help with calculations and information on how components work. There are quizzes to test your knowledge as you progress.

Learn More

How does a radio select one station from all the stations on a band? How does a power supply change AC to DC? How does a lighting dimmer work? Theory is an essential in many branches of electrical and electronic engineering; audio, video, cell phones, motors, lighting and many others use AC components and circuits that act differently to DC circuits. Knowing basic theory helps you understand how such complex circuits work.

Vocational Electronics

The theory in this part of "learnabout-electronics" is designed as a linked set individual learning modules. They can be used as a complete course or separately to fit to fit the way you want to learn. They provide a solid background theory to "hands on" electronics, they also provide useful information and exercises for students at several levels of experience, with many links to electronics industry sites worldwide for further information.

How to use the Step by Step Modules

Select your module

Any of the Step by Step modules can be selected from the menu in the left column, here on the Home Page. Just click the "Back to Index" logo from any module to return here.

Know what you will learn

Each module is divided into several smaller sections or pages and every module and section has a "What You Will Learn panel" that tells you just what you should learn from that module or section.

Check your learning

Revise as you learn with the revision questions in each section, and the "Module Quiz" at the end of the module.

Prefer Paper?

If you would like a paper version of any module to print and keep, click the PDF icon in the left column of each module to download a printable copy of the complete module.

Step by Step

You can select any module or section to study by as each module and section leads on from the previous one, the best way to learn is Step by Step Starting here with Module 1 and studying each section (numbered 1.1, 1.2 etc) in order, then use the revision questions to help check your understanding before going on to Module 2 - and so on.

Translate this site

English not your first language? Did you know you can translate the text on this site to any one of 8 languages? Try it for yourself. Click a flag in the Babelfish box for an instant translation of any page.

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