On Mon, Oct 10, 2022 at 12:20 AM, tuckvk3cca wrote:
If you use a resonant circuit to find the Q, the loss with be combination of
both the L and C. You can only separate it if you can independently measure
the loss of the coil or capacitor without the resonance.
That is why I have the question, from my quick reading of the paper, it seemed like the author separated them, but I agree with you,
at resonance you can't separate them.
Alternatively I would parallel the capacitor with a series of high value resistors R. Measure the Z. Then extrapolate to zero R to find residual R in Z.
By extrapolate to zero, here is about as far as I understand that concept, my example would be finding the output impedance of an amp by taking two measurements with two different value of resistor and extrapolate to find the output impedance.
I expect values under 0.2¦¸ and hopefully less if I have any good air caps.
Is there a math expression that you can tell me to do the extrapolation?
I don't have the math skills to figure that out.
If have that, I can take many measurements over frequency, plug everything into Excel and make graphs of my better capacitors.
Thanks, Mikek
