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Re: Spice simulation pictures




> Richard and All
> 
> Thanks Richard. I accept what you say except as noted above. 
> I don't wish to belabor this and I will shut up after this
> comment/question.
> 
> I have been unable to excite any coil in any fashion and cause it to
> resonate at a frequency equal to the 1/4 wave length frequency of the
> wire of which it is wound. If anyone has I would appreciate hearing the
> dimensions of the device.

If you've made a working Tesla coil, you have been successful - you just
don't realize it. The natural 1/4 wavelength frequency of a coil is the
frequency at which the coil resonates given the time that the e/m wave
takes to propagate down the coil from one end to the other.  As Richard
stated, the propagation velocity down a straight piece of wire floating in
the void and vacuum of outer space would be pretty close to the speed of
light in a vacuum (=C), so the resonant frequency would be close to
wire_length/C. Anything else you do with the wire would change the
inductance and capacitance of your wire "system", which in turn would
affect the propagation velocity.  You would observe a resonant frequency 
different than simply length/C, but it would still be the natural 1/4
wavelength frequency of the wire as a system.  The trick is realizing that
the propagation velocity down a coil is not equal to C.

You can compare this to the index of refraction in optics - light (an e/m
phenomenon) travels fastest in a vacuum, it's velocity in any other medium 
is less.

Steve Roys.