Q: "Can you tell me if yours is a Bi-Phasic design as Bob Beck states it should be to perform well? I mean by Bi-Phasic, to be able to switch between a positive voltage and a negative voltage. Like between +33v and -33v, and not simply between +33v and 0v."
A: Yes it reverses polarity 4-5 times per second (4.3Hz)
The only difference is that you need one 9V battery.
I also would recommend getting the larger 4 inch enclosure that way you do not need to drill into the Radio Shack circuit board and it will fit the CS maker circuit as well. That makes it very easy.