Steve,
I kinda fast-forwarded through the video. After a few shots of the hardware, there's a pretty clear view of a schematic. I didn't listen to the audio, perhaps that sheds some "light".
I still hope the thread's owner will put his schematic up where we can easily see it. A screen capture might actually do well enough.
I don't think videos are the best things to put on these forums, except to clarify a point, or clear up some confusion. I don't know why I happened to actually look at this one. Perhaps was interested because I've done an inverter ballast or two in the distant past. ( Learned that polyester caps won't do for 20kHz power AC.)
Ted
PS I looked again, and saw that the schematic sketch seen in the video did have all the elements of a Royer oscillator, but they are not connected in a way that would work at all. Perhaps the schematic does not match the actual apparatus in the box.
