Overunity Parametric Oscillator?

[neptune]

Here is an idea based on the work of J L Naudin et al .Take a simple parallel tuned circuit [tank circuit] consisting of a coil and a variable capacitor . I understand that it can be made to oscillate by varying either the inductance or capacitance in a rhythmic manner at twice the frequency of the tank circuit . So we are altering a parameter of the oscillator in the same manner that a child maintains oscillation of a swing by rhythmically altering the center of gravity . One way to do this is to have a center tap on the coil,and provide a switch that will short circuit half the windings . Then we open and close this switch at twice the resonant frequency of the tank circuit . In an initial trial , the resonant frequency of the tank could be kept low ,say 50 Hz .Thus the switching could be done mechanically by a variable speed motor driven cam or commutator . I believe that the amplitude of the oscillation is dependent on the magnitude of change in the inductor and possibly the Q of the tank . I think the amount of energy that could be extracted from the tank could exceed the energy needed to do the switching .I favour mechanical switching initially , it saves argument as to where any excess energy comes from . Is it possible for someone to simulate this please?

[neptune]

I am a bit surprised no one has commented on this .It is so simple . Any thoughts , positive or negative?

[MasterPlaster]

http://www.energeticforum.com/97660-post196.html

[neptune]

@Master Plaster . Thanks for taking an interest ,and the link to that interesting post . I am not a brilliant mathematician , to say the least . But I get the feeling that the chances of success would be higher if the coil tap was arranged so that the two switched resonant frequencies were harmonically related .My gut feeling is that the resultant sinewave would be much less distorted .

[MasterPlaster]

This is an old research area.

http://jnaudin.free.fr/html/paraconv.htm

I was looking at parametric converters a few days ago.
Then I fell in to the area of multi-filar windings.