EF,
Electronics is not my long suit--I'm the wrong kind of engineer. I suspect the device works very similar to the receiver in terms of generating the pulse that controls the servo position. It would probably work with another battery in the model and you would only have to connect the signal and ground wires through the control lines. Ground is black, signal white. So you would have a battery in the handle and another one in the model. I know some guys who use the servo drivers but they don't visit this site.

By the way, I have a copy of Fred Cronenwett's book and it is an excellent source of information. He and I have never met, but the techniques I developed on my own before I saw his book are almost exactly as he presents.

Chuck