An apparatus to stimulate resonant frequencies of mammals, including humans, through transcutaneously applied bipolar micro-current therapeutic frequencies eXclusive OR (XOR) modulated over a variable duty cycle carrier square wave. A Fibonacci number clocked stored-program microcontroller generates a variable duty cycle higher frequency pulse width modulation (PWM) carrier square wave output which is XOR modulated with a lower therapeutic frequency square wave output to control an H-Bridge driver capacitive coupled to an isolation transformer. The preferred embodiment supports one or more user inputs and displaying program and operational information on a suitable display. Further, using an H-Bridge to drive an inductive load with bi-polar pulses creates scalar waves when the H-Bridge's output is switched from one polarity to the opposite each time the therapeutic low frequency square wave output XOR modulates the higher frequency PWM square wave.