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Re: Flat coils & undamped waves (was Wire Length)

Original poster: Harvey Norris <harvich@xxxxxxxxx>

--- Tesla list <tesla@xxxxxxxxxx> wrote:

> Original poster: Ed Phillips <evp@xxxxxxxxxxx>
> Original poster: "Lau, Gary" <Gary.Lau@xxxxxx>
> Why is flat coil geometry significant in this or any
> other context?  Is
> there any electrical or functional difference
> between using a flat
> secondary and a helical secondary, beyond one being
> much more difficult
> to fabricate?
Perhaps not on first notice of usage. Shouldnt it be
possible to understand the difficulties of making a
source frequency transformer without iron? In a Tesla
coil the primary can easily be made as a copper tube
primary in form of a spiral, and the secondary
necessarily becomes becomes a helical solenoidal
winding of many turns and  wire length; to convert the
source frequency excitation via spark gap to a higher
frequency whereby the secondary can resonate to, via
the LC combination made with primary arc gap.

However if no spark gap is employed, and only the
spirals themselves are used in mutual inductance,
provided the frequency is high enough, most easily
within 500 hz ferrromagnetic alternator methods, one
spiral adjacent to another at cores should make an
efficient air core transformer, even though no high
frequency effects are made by arc gap.  Essentially
adjacent air core spirals have a high mutual
inductance enabling them to become feasible air core
transformers, without high frequency effects brought
on by arc gap usage.

A most unusual demonstration can be made with a common
3 phase car alternator with  three phase AC outputs.
If three somewhat wider width spirals of some turns
are used: I used Radio Shack Megacable speaker wire
near 1/8 flattened braided wire in a 50 ft spiral
measuring some .2 mh or so, if two sets of these are
used and  and three adjacent indentical winds are
connected to the three phase outputs in WYE, the
fourth winding can be connected to scope to see the
effects of mutual inductance producing three fields in
magnetic cancellation in time.  In this case because
each winding has a high mutual inductance with the
adjacent one; two sources of emf are present on each
winding, both the line connected one and the one by
spiral mutual air core induction. Because two sources
of amperage draw are present on each winding, and if
the windings themselves are of such a low resistance
to approach the Maximum Energy Transfer Principle
using matched internal  stator resistance vs load of
resistance winding, when additional current is created
by mutual inductance of three phase windings, this
drops the output voltage of the alternator well below
its 50% drop experienced in maximum power transfer
where equal heating losses occur between the windings
of emf generation and the heating losses of resistance
load. As defined by law we can produce the maximum
power, but to do this requires a sacrifice of a 50 %
loss of efficiency, theoretically made by equal losses
encountered between the internal stator  winding
heating encountered to drive an external resistance of
equal value.  However this "equal" value of external
resistance load becomes compromised by the fact that
an equal amount of current can be pushed through its
windings alone by almost perfect 100% air core
coupling of spirals surrounded  by the three phase
spiral induction scheme, that might not just employ 3
windings , or 6 or 9 in parallel ect.
     This net effect drives the windings BELOW the
point of maximum energy transfer, so that the stator
voltage drops well below 50 % of its output voltage,
but the currents obtained from this lowered voltage
input are magnified by mutual induction, so that the
lowered voltage input is most efficient on procuring
amperage on its windings. The net effect appears
remarkably as an effect where maximum amperage is
obtained from the alternator with little stator
heating core losses, with a (possible) net gain of
efficiency from the power generation. Also most
remarkable in this circumstance is what happens if a
leg of the three phase accidently goes open circuit
when it should draw no power. The net effect then is
for the source stator to go to its highest possible
voltage, which once again causes high heating effects
from the power delivery source, rendering it the realm
of traditional power transfer laws.