Hear from deep space. Pupils learn how satellites transfer information back to Earth. They learn about three different ways to modulate radio waves and how a satellite sends information with only 0s and 1s. Using sound, class members...

Here is described a simple process to 'put a voice on a sunbeam' and transmit it over a distance. It is a fascinating example of amplitude modulation of light using sound vibrations. It then describes how the modulated light is detected...

A very simple device to convert light into sound can be made by wiring a solar cell directly to headphones (or an earpiece). The solar cell converts light into electricity and the headphones convert electricity into sound. The limitation...

A simple demonstration is described which shows how a transistor works. By including the audience into the actual circuit and by lighting LED's it shows the potential of the simple transistor amplifier. The extension to two transistors -...

Review the key terms and skills related to wave interference, including how to predict wave interference patterns.

With the help of some economics metaphors, Habitat Network delves into the scary-sounding "ecological trap" and helps bring it to light.