Check out this bipolar coil: http://www.youtube.com/watch?v=ULNb0evvV8w&feature=related Some details of the coil are here: http://www.drspark.org/bi_polar%20Assemble.htm Cheers, Hank _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla