i talked to Jon on youtube coments he said that he had wound all coils from end to end,just 1layer per coil.It had a ferite rod(8'' long) with a bifiliar coil first wound(22awg),on top of the bif.,a primary(24awg),and on top of the primary a secoundary(30awg).The pulsing was done with a dave lawton crkt,the 2 freq were combined by a 4093 nand gates,then the signal fed a .800 Volt 9 amp 160 watt STP10NK80Z ,pulsed with 30v.The rest is like jl naudin setup.I made the setup on a shorter rod but with no luck,what i got was 2v across the cell and inverted signal exactly like the input one.Jon said it took him 20 days to find the signal,i think that took him so long because the lawton crkt is crap and when you turn one of the pots you spoil everything,both freq and duty.That is all i gathered from all his posts,hope it helps somebody.Cheers!