There is no matching of frequency on the throwie coil. Just 20-30 turns on a ferrite rod and your good to go. More turns = higher voltage. A ferrite core on the throwie helps couple the power better, but one the squarish green led throwie in the video has no core at all, and still works.
There is no matching of frequency on the throwie coil. Just 20-30 turns on a ferrite rod and your good to go. More turns = higher voltage. A ferrite core on the throwie helps couple the power better, but one the squarish green led throwie in the video has no core at all, and still works.