[rotorwrench]

The Fun Projects VR only controls the amperage output but in doing so, it also controls the voltage to a degree since both increase and decrease at the same time per Ohms Law. The actual voltage control on all 3-brush units is always the battery voltage no matter what type of controller you add.

John Regan's design turns the generator on and off at a rate that acts as a control very much like a 2-brush voltage regulator pole controls the voltage. The on and off cycle is like a buzz since it happens very rapidly depending on the electrical load at any given time.

Birdhaven Vintage Auto Supply purchased the rights to Fun Projects and Texas T Parts but it's hard to tell what they are up to unless you call them. Both the Texas T and Fun Projects web sites are still up but I don't know if they update them or not.