Mr.Clean's Device

[nievesoliveras]

I think the idea is a variation of the circuit found at PJKbook-Chapter-3.
It is like so:

[TinselKoala]

If by "variation" you mean "completely different ".... then I agree with you.

[verpies]

Below is an updated schematic diagram of Mr. Clean's Device.

It is still not clear where the +9V supply rail comes from and where the red question marks (? ? ?) go to.

[TinselKoala]

Thanks, verpies, that's very clear.
The "unconnected parallel wire"... is that half of a pair with the other, connected wire, like lampcord or coax or twisted pair, or is it a separate lead altogether? It would be nice to have the dimensions of this wire, how far apart it is from the other wire, how long, how is it laid out?
I don't really have a theory here, but certainly this is one odd part of the arrangement that should be documented completely.

[poynt99]

Thanks verpies, nice work.

The bottom (? ? ?) must go to the circuit ground. If the 9V supply is derived from the 12V supply (and I suspect it is), then the upper (? ? ?) would go to the 9V regulator input in the PWM block. Kurt does show both going to that block.

Hopefully Kurt will be a little more forthcoming with some answers, then we may know for certain if what I am saying is correct.