That's all the info I have on this one. I think this one is mostly just for experimentation. If you'll notice the info says just a 25% success rate.
But if you want some ideas... How about an audio sine wave generator in place of the transistor radio? Then an amplifier after that. For the step down transformer just try a standard 120volt to 12volt. Radio Shack still has those in stock. The clothes hanger loop with the magnet wire looks to be the most time consuming and tedious part of the project.