I would keep the 30 Khz Zapper that you built. That is the output of the one Dr. Clark recommends. Yes I have read that the
2.5 Khz may be better for zapping. If you can afford to buy one then compare it with the one you built. See if you notice a
difference. If you like to experiment, go to http://www.royalrife.com/zapper727.html. There are a couple of different schematics
you might want to try.