1.  Lindsay's Stack TPU Posted Picture.  All Wound CCW  Collectors three turns and HORIZONTAL, not vertical.

2.  3 Tube amps, sending three frequency's, each having two signals, one in-phase & one inverted 180 deg, opposing signals in each collector (via control wires). 

3.  Collector is Magnetic Loop Antenna, made of lamp chord wire, wound flat.  Inside loop is antenna, outside loop is for output.  First collector is tuned via tuned tank, to the fundamental.  Second collector is tuned tank to the second harmonic (component).  Third collector is tuned tank to the third harmonic (component)  Frequency is determined by taking the circumference frequency, reducing the size by .88 inches.  Divide this frequency by 1000, and you have your second harmonic.  Divide this by 2 and you have your fundamental.  Multiply that by 3 and you have your third harmonic component.  Tune the collectors to each of these.  Input the fundamental and two modulation frequencies, made to create replicas of the fundamental, second harmonic and the third.

4.  The three frequency's circulating in the collectors, both in phase and inverted, begin to create hundreds of thousands of created frequency's, via intermodulation, that subtract to the fundamental and its harmonics.  This is called "Catalyst".

5.  The three AC PURE sine signals, travel through the amplification stage, Nonlinear, producing the second harmonic and third.  (distortion)

6.  These signals then travel the control coils, are rectified by a full wave bridge, and then sent into the output outer loop as all positive pulsed DC.  This then becomes the output and "collects" the current.

P.S.  The Kicks are harmonic distortion with passive intermodulation.  Can't see it without a spectrum analyzer, normally unless trained to see it on a scope.