*Nods* Though much of this knowledge is common sense, common sense is lacking these days. Thanks for the input. I'll post up my findings when I get a change.

But first, at least with these Chinese Clones, I find that the ground (GND) next to the Voltage Input (VCC) on the communications header (the 6 pins on the end of the Mini Pro) is not connected to the Ground (GND) on the other two headers. The only thing I can figure from this that this second GND is a signal ground and not a voltage ground. In my experience I have only seen signal grounds separate from voltage grounds in audio and 2-way radio systems.