Re: Parametric pumping for tesla coils?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

Could one not put mechanical energy into the system in the form of a rotary
capacitor.  Small electrical energy to charge the capacitor, mechanical
energy to make capacitor big, discharge big energy into LC...

Big practical problem: it's gonna be a big rotary capacitor to get 0.03 uF
or so...
 >  >
 >  > Dear List,
 >  > If I may be so bold, I have been thinking that instead of using
switching
 >  > devices to vary currents and voltages as we presently do, how about
 >  > changing say, the capacitance instead -charging at low voltage and
 >  > discharging at high
 >  > since charge ,Q,  on an isolated capacitor doesn't change with a change
in
 >  > capacitance but stored energy and voltage do vary with changes in the
 >  > capacitance.
 >
 > It does of course take at least as much energy to decrease the
 > capacitance as the energy increase in the final reduced capacitance.
 > Where will that energy come from and what sort of capacitor did you
 > have in mind?
 >