Yes, this is confusing to me also HMS, Stan's document shows a separate ground for an optional 'heat resonator'?
The ground seems to be separate from that of the primary and driving circuitry.
I have built that circuit with many variations, and got no results.
I believe Stan left something out intentionally, for patent reasons.
Below is a pic from my scope using Tony's alternating dc circuit which is supposed to heat the water, but so far the only thing it heats is the two 220 ohm resistors, and they get HOT!
The scope is connected at the secondary of the transformer, across the cell.
Water is distilled. Scope is set to 5V / div, so the signal amplitude is approx. 20V.
I am certain the fault lies somewhere in my transformer construction, which only Tony knows how to build correctly.
My transformer consists of approx. 600 turns 29AWG magnet wire primary and 3000 turns 29AWG magnet wire secondary, on a ferrite rod with permeability of 200.
It can't be anything else, because the waveforms and circuit seem to be working correctly...
I am not giving up though - each day you fail is one day closer to success!