Correct.
Dave - W?LEV
On Tue, Oct 12, 2021 at 7:00 PM Andrew Kurtz via groups.io <adkurtz=
[email protected]> wrote:
Sounds intriguing! I routinely find self-resonance and calculate
parasitic C from that. I see that I could take that R and calculate Q, but
the Q would be for a frequency far from a practical one, and thus that Q
would not relate to my coil when in use¡ Agree?
Andy
On Oct 12, 2021, at 11:15 AM, Gary Rondeau <grondeau@...> wrote:
Quick and dirty method... Just measure the self resonance of your
coil. If you calibrate the nVNA to your fixture and then just run the S11
sweep up high enough on the coil, you will undoubtedly see a resonant
peak. At low frequency you can determine the inductor, L. (the nVNA saver
software will do this for you) The frequency of the peak tells you the self
resonant parasitic capacitance, C. From the magnitude of the the
resistance, R, measured at self resonance, and the calculated self resonant
impedance, Z=sqrt(L/C), then Q will be R/Z.
This procedure also shows you explicitly when parasitic capacitance
becomes important -- which it often does!
--
*Dave - W?LEV*
*Just Let Darwin Work*
