Practical Guige to Free Energy Devices

No one part of an induction coil may be developed to its maximum efficiency without seriously influencing and
lowering the efficiency of the other parts. The following suggestions regarding the construction are given so that
they may prove to be a useful guide for the amateur coil builder. The parts will be considered in their natural
order of construction.
Core: Some experimenters who are not quite familiar with the principles of magnetism, think that if an induction
coil were provided with a closed core like that of a transformer, then the efficiency of the coil would be materially
increased. But that is not the case because then the magnetisation and demagnetisation of the iron cannot take
place rapidly enough in a closed core when an interrupted direct current is used instead of an alternating current.
The core of an induction coil is therefore always straight. For the same reason, it is never solid but instead is
always made up of a bundle of soft iron wires in order that rapid changes in magnetism may take place. The
wires are always of as high a permeability (magnetic conductance) as possible so as to create a strong magnetic
field. Swedish or Russian iron of good quality is the best as its hysteresis losses are small. The smaller the
diameter of the wire, the less will be the eddy current losses and consequent heating, but the permeability is also
reduced and the core will not be so effective, as the amount of iron is thereby decreased and the oxidised surface
increased. No. 22 gauge wire is the best size for the average core.
Wires of a good quality may be purchased already cut to various lengths. To buy them in this form will save a
great deal of the labour required when building a core. If the wires are not quite straight, they may be
straightened by rolling them, one at a time, between two boards. It is best to re-anneal the wires. To do this,
place the wires in an iron pipe and plug the ends of the pipe with clay. Then lay it in a coal fire until the whole
mass reaches a red heat. The fire is then allowed to die out gradually, with the pipe and wires remaining in the
ashes until cool. When cool, remove them from the pipe and rub each one with emery paper until bright. After
this cleaning, the wires are dipped in hot water and then dried. They are then dipped in a good quality varnish
and allowed to dry again.
The varnish provides a resistance to the flow of eddy currents in the core and reduces those losses very
considerably. A strong paper tube having an internal diameter equal to the diameter of the finished core is made
by rolling the paper on a form and cementing it with shellac. When it is perfectly dry, the tube is removed and the
wires packed tightly inside it. The following table gives the core dimensions for practical coils of different sizes:
CORE DIMENSIONS
Spark Length Core Diameter Core Length
0.5 inch (12 mm) 0.5 inch (12 mm) 6 inches (150 mm)
1 inch (25 mm) 1 inch (25 mm) 8 inches (200 mm)
2 inches (50 mm) 1.25 inches (31 mm) 10.5 inches (262 mm)
4 inches (100 mm) 1.375 inches (34 mm) 12 inches (300 mm)
6 inches (150 mm) 1.5 inches (38 mm) 14 inches (350 mm)
Primary Winding: The ratio of the number of primary turns of an induction coil to the number of secondary turns,
bears no relation to the ratio of the primary and secondary currents. It has been found in practice, that two layers
of wire wound tightly on the core, form the best primary. The primary should always be thoroughly covered with
shellac or other insulating varnish. Since there is almost no ventilation in the primary, the wire must be large
enough to avoid all heating. A table containing the various sizes of primary wires is given here:
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