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I have to test a quartz crystal and I am not sure what What does it mean to have a low quality factor for an RLC circuit? Does the value of this factor has anything to do with the frequency?

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    \$\begingroup\$ 1) crystals have a very high quality factor, like 100000 isn't exceptional. 2) Why don't you look up the definition of Q, the quality factor, for an RLC resonator. You cannot avoid learning at least some basic theory on the subject before you can start working on this. Really, if you don't understand you will fail to bring this to a happy end. Oh and we don't explain basic theory here, there's no need because it is already explained in many other places. \$\endgroup\$ Aug 23, 2019 at 14:30

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Quality factor when applied to a crystal resonator refers to the ratio of energy shuttled between Ls and Cs, to the energy dissipated by Rs.
These three components (Ls, Cs, Rs) are electrical representations to the mechanical motion of the crystal. Their values can be found by making electrical measurements at the crystal's two terminals. This measurement is done at the crystal's series-resonant frequency: \$ f_{series} = {1\over{2\pi\sqrt{L_s C_s}}}\$.

The component Cp is an actual capacitance between the two plates of the crystal. It is generally measured at a frequency far removed from the crystal's resonant frequency (usually at a much lower frequency).

Quality factor Q = \$ {2\pi f_{series} L_s}/R_s \$.

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