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Re: Re: Resonance



> I used my scope and funtion gen. Fed sine wave intp base of coil and
> hooked scope to other end of coil. I increased frequency until wave form
> grew in voltage. That I assumed was the resonance point. Is this wrong?

Yes - first, the scope probe loads up the coil, and then the probe also has
some capacitance, both of which make the coil resonate at a different
frequency than the "free" resonance. I know, I did the same mistake earlier.
I measured 190 kHz by connecting the probe to the top of the coil. Now, by
measuring the frequency, with me as the antenna, touching the tip of the
probe,
standing about a meter away from the coil, it was 305 kHz. It's such a big
difference... (FYI - 10.7 cm dia. by 40.5 cm length, wound with 0.315mm wire).