I have a schematic I could post of one of these doo-dads but not sure if it would do you much good. The reason, well when I built the circuit my intention was to use a voltage generator to help track down a leak in my pond. Needless to say it didn't work but one side affect was that I noticed when I turned it on and adjusted the frequency, some fish would surface. And I'm not talking float, more like they were coming to the surface to feed real quick and then back down. Not enough time to see much.
