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AC Electronics for Alien Minds

(C)2000 William Beaty

FIG.1 Wrap an AC coil around an iron rod, and you have an inductor. But wrap your coil around an iron RING, and you form a "toroidial inductor."

FIG. 2 A toroidial inductor is interesting because the induced magnetic field remains hidden within the iron core. If the coil was wrapped around the entire core rather than in one spot as shown, then the magnetic field would exist only within the iron core.

FIG. 3 Even if the coil of wire does not touch the core, it still induces a strong magnetic field inside the core. The gap between the coil and the iron ring can be very large, yet this does not reduce the strength of the field within the core.

FIG. 4 Although the magnetic field stays inside, something else does come out of the core. The changing field within the core produces a field of Vector Potential which surrounds the core. This field is commonly called the "A-field."

FIG. 5 We can intercept the A-field by passing a wire through the hole in the iron ring. This produces a voltage at the ends of the wire, and this voltage can operate an ordinary load such as a light bulb.

FIG. 6 Perhaps this figure is more familar to you. The wire which intercepts the lines of "A-field flux" is simply the secondary of a transformer. Note that whenever multiple turns are passed through the hole in the iron ring, the output voltage rises proportionally. Two turns gives 2x the voltage of a single turn.

FIG. 7 We can route the "secondary" wire through another iron ring. It will produce a strong field within that second ring, and if we add a "secondary" to that ring, we'll see an output voltage. It acts like any other transformer, even though there is an extra stage of "A-field" linkage.

FIG. 8 What if we don't use wire? If we simply place the second iron core near the first, then the lines of A-field flux will pass through both and link them together. The result? Nothing! No magnetic field appears in the second core, and the extra secondary does not produce any output voltage as it did in figure seven. WHY?!!! I don't know. I haven't thought deeply enough about this yet...

FIG. 9 The A-field is associated with voltage and electrostatic fields. After all, if we add more turns to a transformer secondary, we get more voltage on the output. Perhaps we can use capacitor plates to intercept the A-field? What will happen? Can we extract energy from the toroid without passing an electric current through the central hole? I don't know.

FIG. 10 In figure seven we formed a strange transformer by passing a conductive ring through two ferrous rings. This idea can be extended to ridiculous lengths. If the iron cores are not lossy (use laminations,) and if the conductive rings are not resistive (use thick copper), then a long chain of alternating rings will transmit energy with little loss and no possibility of electrocution. The rings need not even touch each other.

(Just what is Electrical Energy, if it can flow through such a strange transmission line?)

FIG. 11 Figure ten might seem weird, but even a simple transformer is weird in the same way. Stretch the core so that the primary and secondary are far apart. Energy is flowing along the two sides of the core, proceeding from the primary coil to the secondary. Note that the transformer core need not be conductive. It could be made of insulating ferrite.

FIG. 12 With high-mu materials, the transformer core could even take the form of wires. But these wires are nonconductors. They "conduct" waves of magnetic field. The electrical energy is guided by the spin-flipping of electrons in the iron atoms, as opposed to copper wires where energy is guided by flowing electrons.

FIG. 13 Add a SPST switch to the previous "circuit", and we can break the connection between the two halves. A physical switch isn't required: instead we could place a permanent magnet against the wire and cause it to saturate and become magnetically "nonconductive." Note that opening this switch reduces the inductance of the iron ring, and causes the primary to draw an enormous current. BREAKING THE CIRUICT PRODUCES A "SHORT CIRCUIT" EFFECT!

FIG. 14 Now that we've got a wire, lets wind a coil. But what will such a coil produce? A-field! Many turns of ferrous core-wire will give us a higher output voltage, just as many turns of copper wire passing through one turn of iron core gives higher voltage.

FIG. 15 Let's add a core! Barium Titanate should work. Or PZT ceramic (Lead Zirconate Titanate.) Our "coil" should attract such a core, which means we could build a solenoid actuator. Or a motor. Or just use the PZT core to pick up certain things. Things like lint, and little bits of paper. It's not an electromagnet, it's an electro-electret!

OK, my brain hurts now. One last thing. Look at figure fifteen and imagine all sorts of "magnetic circuitry." Is there a magnetic equivalent of the vacuum tube or transistor? The heater or light bulb? And can we extend that PZT core into a ring of PZT wire, to create insulating electric circuitry which conducts only displacement current?! Yow!

James Clerk Maxwell might be spinning in his grave. But is he rotating around his long axis, or flipping endwise?!!!

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" Maxwell places as primary something he calls "electromagnetic momentum"  
(because its time derivative is force). Electric and magnetic fields are
secondary. His friend, Michael Faraday, who originated the field concept
as an alternative to the then popular "action at a distance," called it
the "electrotonic state." It is, Faraday said, changes in the electrotonic
state surrounding magnets that cause magnetic induction. Maxwell
formalized Faraday's field concept. The electrotonic state is today called
the magnetic vector potential, usually introduced only in graduate level
EM courses as a side-effect of a cute little vector identity (primacy of
the vector potential is returning to popularity in physics).

Maxwell viewed magnetic vector potential as primary (presumably why he
gave it the symbol A) and magnetic field as secondary (presumably why he
gave it the symbol B). However, by making the vector (and scalar)
potentials primary, Maxwell's equations became complicated. And so, very
few took the time to learn them."   -- JC Rautio, 2008

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