Re: Tesla Coil Operation - was "Harmonics"

John H. Couture wrote:

>   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.

The differential equations that describe both systems are practically
identical (the mechanical system is a bit nonlinear), and so we can
say that both system work with the same dynamics. If you want a
mechanical system with "action at distance", make two pendulums using
bar magnets as the weights, both with the same vertical orientation,
so there is some repulsion between them. Add weight to one of them
to make it the "primary oscillator", tune both to the same frequency
by adjusting the lenght of one of the strings (ideally identical),
and set the "primary" in oscillation. The energy transfer is not
as in the case with mechanical coupling (this time there is only
repulsion), but the final effect will be similar, with energy
being transferred gradually from the primary to the secondary and
back. (I have just tested the idea. It works, but as there is no
equivalent to a transformer in the system, the energy is never
completely transferred to the secondary pendulum. The primary 
oscillates with a small variation in amplitude and the secondary
shows beats. The same happens in the mechanical analog if the 
connection bar is horizontal).
>   We call this the magic of electrical induction. We can thank Michael
> Faraday for making this discovery. 

Don't forget electrostatic forces, known since antiquity.

>   The Tesla coil is a special type of transformer that Tesla invented to
> make it possible to distribute electricity around the world without wires.

This never worked, and very probably would never work...

Antonio Carlos M. de Queiroz