Tesla's "COIL FOR ELECTRO-MAGNETS".

[Farmhand]

Hi all, This coil arrangement is an interesting one for many of us so this thread is for discussion of the coil and it's uses/effects.
This includes all types of coils as stated by Tesla in the patent. Careful reading of the patent is encouraged. 

Patent 512340 "COIL FOR ELECTRO_MAGNETS"
http://www.google.com/patents?id=baRZAAAAEBAJ&printsec=abstract&zoom=4#v=onepage&q&f=false

Lines 33 to 38 of Page one of the patent.

I would here state that by the term coils I desire to include generally helices solenoids or in fact any conductor the different parts of which by the requirements of its application or use are brought into such relations with each other as to materially increase the self induction.

There is a lot of discussion in a thread here --  http://www.overunity.com/11350/confirming-the-delayed-lenz-effect/975/#.UXPhyrXPVqA
Starting at about page 67.

I wanted to bring the discussion to a more appropriate place.

I've done some testing and will elaborate in my next post.

Regards all.

[Farmhand]

Ok so I wound two coils, both with the same length of wire, (measured and cut side by side).  Wire is 0.5 mm enameled wire,
wire length is about 4.35 meters in each coil. The coils are each wound on individual iron powder cylinders 38 mm long x 10 mm diameter.
The core is insulated by home made bee's wax paper and each layer is insulated by a sheet of bee's wax paper as well, there are about 2.5 layers.

Here are the specs.

Single winding coil (control coil)

Turns - 140 (approx.)
Resistance - 0.2 Ohms
Inductance - 401 uH
Capacitance - 43.4 pF (determined)
Resonant Frequency - 1210 kHz (By experiment, square wave excitation)

---...---

Serial connected bifilar coil. "COIL FOR ELECTRO-MAGNETS"

Turns - 140 (approx.)
Resistance - 0.2 Ohms
Inductance - 406 uH
Capacitance - 117 pF (determined)
Resonant Frequency - 735 kHz (By experiment, square wave excitation)

Capacitance between open windings - 410 pF (measured)

Attached is some pictures and scope shots. Last is the coils and how they are connected for testing,
there is a 10 K resistor is series with the function generator.

The shots show the single winding control coil, first at resonance, then at a harmonic,
then the last two shots are the serial connected bifilar coil.

EDIT: I think the last scope shot is the wrong one, I'll see if I can find the correct shot,
the scope can be tricked into reading the incorrect frequency by the harmonics. 

Correct shot found and added.

Cheers

[MileHigh]

Farmhand:

I think I saw you make reference to the harmonics present in a square wave and how they might possibly be picked up by a ball magnet rotor to make it spin very fast.

The same idea applies to when you are sweeping frequencies with your signal generator to find the resonant frequency of your coil.  You must use a "pure tone" without any harmonics present - a sine wave.

MileHigh

[Farmhand]

Farmhand:

I think I saw you make reference to the harmonics present in a square wave and how they might possibly be picked up by a ball magnet rotor to make it spin very fast.

The same idea applies to when you are sweeping frequencies with your signal generator to find the resonant frequency of your coil.  You must use a "pure tone" without any harmonics present - a sine wave.

MileHigh

Yes I am aware of that. Thanks. One shot is the resonant frequency for that coil and one shot is one of the harmonics of the coil.
I did that for each coil. First two shots are for the single wound coil and the second two shots are for the bifilar coil.

The function generator doesn't lie. It tells me the frequency in numbers when I see resonance. Meaning when all the harmonics disappear.
That's why I use the square wave to excite the coils. Full resonance is very obvious. I do know how to find the resonant frequency of a coil
with a function generator and a scope.

The coils have very different resonant frequencies.

..

[synchro1]

My double strength "SB Spiral" monopole:

Quote from Farmhand:

                                          "The coils have very different resonant frequencies"

Farmhand's SBC resonant frequency is in tune with the oscillating frequency of magnatisem. 7.83 Hz for Schumann resonance is nearly a thousand times less then the 735 khz, but on a close harmonic. The SBC resonant frequency is in L-C synch with Earth's pole resonance, along with the neo sphere's inherent magnetic oscillation frequency.