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Re: Elementary Lecture

On 02/26/99 06:38:23 you wrote:
>
>Original Poster: "Dr. Resonance" <Dr.Resonance-at-next-wave-dot-net> 
>
>to: Dave Hartwick
>
>It's not magic -- it's physics.  A Tesla coil produces "displacement
>currents" in air because the air represents a dielectric while the terminal
>represents a plate of a capacitor.  The second plate is represented by
>isotropic capacitance and plate to ground capacitance of nearby room walls,
>etc.  A displacement current has unique and different properties than normal
>air to ground currents which produce the wandering spark phenomonea of Tesla
>oscillators.
>
>You might read some early Maxwell for good descriptions of displacement
>currents.
>
>Regards,
>
>Dr.Resonance-at-next-wave-dot-net
>
>

2/26/99

While it's true Maxwell created the myth of "displacement current" in a
dielectric, he did so 
only to enable his theories to work.  Maxwell never demonstrated or proved
that displacement 
currents exist in a dielectric.  Neither has anyone else to my knowledge.
Dielectrics have been 
studied with exquisitely sensitive Squid devices and to date no
displacement currents have 
ever been found to exist.  

The question posed is a good one and deserves an answer.  However, I
believe it is not 
explainable with current displacement theory.  It is true that TCs
represent two capacitor 
plates and air dielectric between, as pointed out above.  The air
dielectric is constantly being 
charged by constantly varying electrostatic fields.  As gas ionization
takes place conductive 
discharge channels are formed which readily conduct electrical discharges.
These discharges are 
electrodynamic and do conduct current both to ground and to the
electrostatic field in the 
surrounding local environment.  This electrostatic discharge mechanism is
the same for van de 
Graf generators or natural lightning.  It all starts out as an
electrostatic thing.

As an aside, the term "electrostatic" is a very outdated misnomer in the
context of Tesla       
coils.  These TC ES fields are anything but static in that their amplitudes
constantly vary and 
field polarity reverses twice during each cycle.  Varying ES fields are not
the same as 
electromagnetic fields also surrounding TCs.  The two field types coexist
concommitantly and do 
not interfere with each other.

Richard Wall