Day One

Jonathan and I have done something like this once before in Cariacou - we made a radio transmitter and receiver that meant we could communicate across a distance of a whole 15 metres. That is an easily shoutable distance. So we needed to do better than that, really!

To communicate across space it's just not possible to use sound waves. Sound relies on air as a medium so, since space is effectively a vacuum, no sounds can be heard. We can only hear on Earth because we exist in an atmosphere with air. So light is the obvious thing to use to try carrying a message, since it can travel across a vacuum without any problem. But we still need to capture the sound of a voice somehow on the light beam.

We had a small laser pointer, but frankly light from the sun here is so intense that it makes more sense to try and capture that somehow. Jonathan gets cannibalising an old radio to get hold of the transistors. They're sensitive to light, usefully. I make a load of light reflectors. Since we're not sure what we need or what will be most effective, I make lots to try out. Really have no idea which will work best.

It's a lovely idea - light carrying the vibrations of a voice, so you can pick it up somewhere else. Just detect the changes in the light, turn it all into an electrical signal, amplify then feed it to a loudspeaker. Sounds simple - perhaps too simple.