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Re: Induction heating in toroid / short circuit of secondary

> >  Thats why I question EM Vs ES field influence.
> >  From my tests, I would conclude the whole effect is ES.
> >  Same max ppArc, same corona inhibition, eliminates turn to turn
> >arcs, etc.  The shorted turn EM fails to alter any operating
characteristic,
> >perceivable.
> >
> If you mean by ES, electro-static field, I don't think there is one:
> "static", after all, means "standing still".  That is, a bunch of
> electrons just sitting there.  Not so, in a t.c.  But I'm sure you mean
> the more general <electric field<, in which case, I don't see how such a
> field (from the toroid, presumably) is going to affect the secondary
> much.  (But the electric field--I assume from the secondary--surely
> affects the fluorescent lights in my workshop: those 8' tubes blink
> brightly with every "bang".)

===============================================================

In a non-discharging disruptive TC, fields at the termination (top) of the
coil are almost exclusively "elecrostatic" or electric if you will.  Current
and and magnetic fields are nil.  This can be demonstrated experimentally.
There is really little magnetic field at the top of the coil with which any
shorted turn toroid magnetic field may interact.

There are huge alternating electrostatic fields though.  Despite the term
"static" these very high E field potentials are varying in reference to RF
ground from positive to negative every 180 elecrical degrees.  The vast
majority of coilers are under the mistaken impression that energy of a
single polarity (similar to a van deGraf generator) is built up and stored
in the toroid.  And, after reaching sufficently high potential a discharge
is initiated.  Not so, the toroid is a very busy place with polarity
changing from positive to negative and back with refernce to RF ground at
the resonating frequency of the Tesla coil.  There is resonate rise and
positive-negative potential swings may reach hundreds of kilovolts before
breakout occurs.

During the heyday of electrostatics, indeed, all known electricity was
"static".  During Franklin's day the only "dynamic" electricity that occured
was lightning.  Subsequently as electrodynamics evolved electrostatics was
almost forgotten and became a curious electrical relic.  Describing
"electrostatic" electricity as dynamically changing is not an oxymoron.  As
it turns out, "static electricity" may (or may not) have a dynamic componet,
but not in the well known EM model.  I know using the older term "static" in
a dynamic sense may be confusing, but think of an electrical field where
only the amplitude of the *potential* varies with time.  There is no
associated magnetic field.  There is no movement of charge, current or
magnetic flux.

Experiments abound to demonstrate these dynamically changing electric
fields.  These simple experiments are designed to detect varying electric
fields unassociated with magnetic fields.  It is very important to choose
proper instrumentation that will only detect either the electric or
magnertic field and totally reject the other.  For ES instruments choose
very high input impedance instruments (teraohms for some ICs is good) and
high CMRR (> 90 dB) to eleminate common EM signals.  I build most of my own
from precision differential instrument op amps.  A good cheap source is
Burr-Brown from Digikey.  Others like Richard Hull use high grade
electrometers such as Keithley.  Richard has also designed a cheap
electrometer which I believe he has placed in the public domain.  See
HVlist.  Older ES volt meters also work great.  Absolutely no EM with these
machines.

For magnetic field instruments I use small coils, either air core or wound
on ferrite cores.  I have used Hall IC devices.  There is also a
magnetometer IC by Philips for under $20, but I have not used this one.  Of
course, the SQUID is the most sensitive magnetic field detection device, but
few of us will ever see one.

Here are a few very simple, but powerful, experiments you may wish to try.
Remember it is imperative to know the reference point from which you are
measuring each and every time.

1.  Wiggle wand experiments made famous by Charles Yost.  While an
electrometer is nice, I have done this one with a ball electrode receiver
and an oscilloscope.  Simply electrostatically charge a plastic rod and wave
it to and fro in front of the "receiver".  By varying the distance between
charged bodies the ES potential varies between them.  Coulomb's law of
course, but there is no doubt that the amplitude of the ES potential varies
dynamically.  There is no magnetic component.

2.   Place a disk on a variable speed motor.  Attach either a magnet or a
charged dielectric that is counter weighted on the other side of the disk.
If a charged capacitor is used be sure to have one plate on one side of the
disk and the other plate on the other side and measure on opposite sides.
Remember always be sure of the reference point.  This is a variation on the
wiggle wand experiment, but a sine wave can be received on an oscilloscope.
Both the magnet and charged dielectric (ES) waves are dynamically detected
but only with their appropriate detector -- never both EM or ES on the same
type detector.

3.   With a variable HV DC power supply carefully charge a HV capacitor lead
while measuring the other plate electrostatically (no direct connection).
Remember the reference point.  Varying the charging rate of the dielectric
varies the ES potential on the opposite plate.  There is no detectible
current moving through the dielectric even using the most powerfiul SQUID
device.  BE VERY CAREFUL with this experiment and be sure to fully discharge
the capacitor afterward.

4.   Measuring TC and van deGraf generator ES and EM potentials with these
instruments is most interesting.  Who can deny that a van deGraf is anything
but an electrostatic machine and seeing the top potential dynamically
increase is experimental proof that changing ES potentials in fact may vary
dynamically?  A significant amount of data may be amassed in this way
regarding both EM and ES fields, their interactions and dynamic nature.
Terry's fiber optic system makes this type of experimenting immeasurably
safer.

So what?  What good is an outmoded form of electricity in this modern day
and age?  Ever hear of vacuum tubes, CRTs, oscilloscopes, linear
acelerators, CMOS, MOS, FETS, MOSFETS, IGBTS, ES copiers et cetera, et
cetera . . .  ?

Now Tesla Coils?


Have fun experimenting and be safe.

Happy Holidays,

RWW