tnx for help. i know this question isn't concern to topic but: what's the difference of geissler and crookes tube? and according to javatc my coil produces 485 KVs. 14 turns of PRI : vertical conical ~ 1700 turns of SEC on 11 cm in dia pipe. 12KV 30 mA NST no topload = ~ 20 cm streamers cap ~ 15nF PPC by glass and aluminum foil