How to Twang a Tune

Ever wondered how a radio works? You twang it.

Here's how:

Timmy Mallett talks, and the moving air which is the sound of his voice jiggles a magnet inside a microphone, and his voice is converted into electrical squiggles in a wire.

This is then carried, amplified, and these signals are converted into jiggling bits in a large metal pole (we call this an Antenna). (The bits that jiggle are called "electrons")

The jiggling creates radio waves that move through the air at the speed of light and eventually end up being picked up by a smaller Antenna (your radio), where the opposite happens - the radio waves start to jiggle the bits in the receiving Antenna.

These electrical jiggles are fed into one of "these circuits"

(Use the back button to get back here)

This is called an LCR circuit and consists of the tuning process. The signals leaving the radio station have a very definite frequency. The LCR circuit vibrates with another frequency.

How do we make certain they match? Simple. We twiddle a knob which changes the value of the capacitor, changing the frequency of the circuit. It's just the same when you twang a ruler - different lengths of ruler give different twangs, only with a radio, the value of the capacitor, not the length of the ruler, determines which "twang" the circuit will pick up from all the many different radio waves in the air.

Now, in the computer age, the capacitors of old have all been replaced by other things, but the principle is exactly the same.

You twang or tune your circuit to the frequency of the radio station you want to listen to. Even if it IS Timmy Mallett.