Coil Tuning

[Super God]

I have a bifilar coil.  I want to find it's resonant frequency.  How would I go about doing that?  What am I looking for?  Peak voltage output over a given frequency range?  Peak current?  No current?  Could an electrical engineer clear this up for me?

[tak22]

I can't tell you exactly how to do it, but I can highly recommend the resonance series
that user armagdn03 is kindly working on over here:

http://www.forgotten-genius.com/documents/pg__2_2.html

tak

[TinselKoala]

Well, I'm no EE, but sometimes I play one on TV...

There are many different kinds of "bifilar" coils. Your exact procedure may vary according to which one of the many types you have.
But the basic way to find a resonance is really easy. You need some wire, a 1 megohm resistor, a 50-ohm resistor, a signal generator, and an oscilloscope.
Hook the ground of the 10x scope probe to the bottom of your bifilar coil. Hook the 1 megohm resistor to the top of the coil, and the scope probe to the resistor. Loop a couple turns of any old wire loosely around your coil. Hook the signal generator output ground to one end of this wire. Hook the 50-ohm resistor to the other end of the wire, and hook the signal generator output to the resistor. So you've got the SG, the 50 ohm, and the wire loops in series as a primary, and you've got the bifilar coil, the 1-megohm, and the scope as the secondary. Now start sweeping the generator using a low-amplitude square wave, and watch the oscilloscope voltage. As you approach the resonant frequency, you will see the voltage on the scope go up. Way up.
You will most likely find several peaks. Don't give up at the first one you find!

(Thanks for that excellent link, tak22! There's a lot of excellent stuff in there, for Tesla fans and those who are working with resonant circuits.)

[nievesoliveras]

@super

Included is a pdf file that is a resonance tutorial.

Jesus

Edit:

I tried to post a 600kb file and it is not accepted.

But I made a composition of the major points.
I do recomend that you make a search for resonance tutorial on the internet and the pdf file will show up.

Jesus