Inductive kick

[raburgeson]

Would like to here from you guys on this. What delivers the most powerful inductive kick
an electro-magnet, coil, some special inductor? I ask about circuits that don't require
super cooling or have other unique needs of course.

[Elvis Oswald]

A simple experiment with a 9v battery and a nail and some wire will show you that bifilar winding gives you a stronger magnet than just regular winding. 

And... a tank circuit resonating with the source will produce a "shitload" of inductance in the core of the coil.

[magnetoelastic]

A bifilar winding denotes two, tightly coupled windings traveling the same direction.  If the two windings are connected in parallel, you get actually less inductance than if you used a single winding with the same number of turns, because each of the two windings is less tightly coupled to the ferromagnetic core.  If the two windings are connected in series, it is the same effect as if you had a single winding with double the number of turns - which in effect you are creating.  If the two windings are connected anti-parallel, you get far less inductance that either of the other two conditions, because the fields of the two windings tend to oppose.
Bifilar windings are of particular utility in constructing transformers, not inductors.

[magnetoelastic]

To obtain the greatest inductive 'kick, you need the following:  Maximum inductance, maximum capacity for stored energy (from a gapped core), and a laminated core construction to minimize eddy currents when the current is interrupted.  Look for an old radio filter choke - like 10 henries at 100 mA is a common value.  A 9volt battery across that will lay you on your tail.  Fair Radio Sales should have them.

[Elvis Oswald]

Well... if you take two nails...
wind one with 100 turns of wire...
then wind the other with 50 turns using two wires together...
and connect them in series -
so that you have basically two 50 turn coils...
in series but interleaved...
and yes this is a bifilar winding...
Connect each of them to a battery and see how much each will pick up.

You will see that the bifilar winding has more magnetic strength.

This is an experiment that you can easily duplicate so that we will all be on the same page. 

Does this not prove that a bifilar winding - in series - will store more energy - using the same source and the same number of turns??