Making a glass Fresnel lens with its concentric rings requires even more work, but as the ever-resourceful [Robert Murray-Smith] shows us, a Fresnel lens can be made from far more mundane materials.

But as demonstrated by [Robert Murray-Smith], it’s possible to generate electrical power from wind without any moving parts. With simple components, he shows how you can build a device capable ...

It’s this last type that [Robert Murray-Smith] has taken a look at, making what he positions as the simplest inverter that it’s possible. If you’ve ever played with relays, you’ll probably ...

The huge turbines visible on the horizon from where this is being written are the upper end of the scale though, and along comes [Robert Murray Smith] with the opposite, probably the simplest and ...