Adjust the potential meter resistor from 1%-99%. Instead of lowering the current or voltage it cuts off the AC wave to reduce the average power to the load to blend at 60Hz. There is no voltage drop at any of the components to cause more efficient power and no heat burning em' up. The transistors on the right make up the TRIAC(for switching "on" or "off" digitally and amplification) and the transistors in the center make up the DIAC(only for higher AC voltage drop).
