Re: Tesla Coil Operation - was "Harmonics"

  Antonio -

  I think that any mechanical anology of the Tesla coil operation can only
be a poor example of how the TC works. Being an electrical engineer I look
at the TC transformer as part of an energy transfer system that can be used
to transfer energy from a power source to a load. With the Tesla coil the
energy is transferred from the primary coil to the secondary coil with no
physical connection between the coils. There is no mechanical device that
can replicate this kind of electrical magic.

  We call this the magic of electrical induction. We can thank Michael
Faraday for making this discovery. In his day the only way to transfer
energy from a power source like a water wheel to a load like a mill grinder
was mechanically by using belts, pulleys, gears, levers, etc. This meant the
load had to be physically connected and close to the source. Faraday's
induction or "action at a distance" discovery made it possible to build
generators, transformers, and motors and the load could be hundreds of miles
from the power source. All of these devices have no physical connection
between the input and the output for transferring the energy. The energy is
transferred by induction via air gaps or "action at a distance".

  The Tesla coil is a special type of transformer that Tesla invented to
make it possible to distribute electricity around the world without wires.
With this system there is no physical connection between the input and
output of the TC and also no physical connection between the TC and the
load. Tesla was not able to finish the task but maybe someday in the future
this will be possible.

  John Couture


At 06:54 AM 1/17/99 -0700, you wrote:
>Original Poster: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br> 
>John H. Couture wrote:
>>   The Tesla coil operation has no mechanical or other electrical analogy.
>It has. Two pendulums (penduli?) with identical lengths (same resonant
>frequency) and different weights (different impedance levels) are
>coupled in a way that produces a high swing in the lighter pendulum
>when the swing in the heavier pendulum is small (a transformer
>with high turns ratio). This may be a light inclinated bar connected
>to their strings (use a fixed width font to see the ASCII drawing):
>       ==+===+==
>         |   |
>         |\  |
>         | \ |
>         |  \|
>         |   |
>         o   O
>If you set the heavier pendulum in motion ("O", the "primary"), it
>will make the lighter pendulum ("o", the "secondary") swing with
>increasing amplitude, as its swing amplitude decays. Eventually
>only the lighter pendulum is oscillating, and the process reverts.
>The result is the same beating oscillations observed in Tesla coils. 
>I tried this experiment, and it works perfectly.
>No sparks, of course ;)
>Antonio Carlos M. de Queiroz