Okay, so it's not quite radio related, but it
is electrical. Meet the worlds most in-efficent solar cell! Maximum output acheived so far is a whopping 0.94 Volts, DC.
http://i148.photobucket.com/albums/s...multimeter.jpg
This slightly unusual project has been 'stewing' for a little while, and yesterday finally got put together. The 'cell' is contained in an old lemonade bottle, with the top removed. Inside are two metal plates, one of copper and one of copper oxide. In between is electrolyte, water saturated with dissolved salt.
http://i148.photobucket.com/albums/s...esolarcell.jpg
Now, apparently I am 'gifted and talented' at science. This doesn't really have any practical upshot, except that I get to use the science labs for an hour after school on a wednesday - but with supervision. We can do pretty much what we like, so long as it doesn't involve making lethal weapons or consists of a danger to life. To get a sheet of copper oxide, a sheet of pure copper was heated until cherry-red by a bunson burner. This is then allowed to cool, and the diffrent rates of cooling and contraction between the red and black copper oxides result in hot black copper pieces pinging several feet. Very entertaining to watch!
Now, there is some reason why this 'cell' produces power when exposed to sunlight, but i seriously can't remember. I also suspect that having the two diffrent metals in a salt water solution is creating a simple battery, as the voltage doesn't drop below 0.1V, even at night.
Anyway, to actually power anything off it, you'd probably need a window four miles long filled with them. I don't think its the answer to global warming just yet. But if you can think of something for it to power, drop us a line!