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  1. #1
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    Tuning Selectivity Factor

    Hi.
    Which tuning coil yields a better selectivity Q factor by itself on a resonant LC circuit, one made with a thin or a thick conductor ?

    What about the capacitor; which type/attributes contribute to better selectivity ?
    Abolish the deciBel !

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  2. #2
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    Re: Tuning Selectivity Factor

    Q=R*SQRT(C/L) so L value must be as low as possible,C must be as high as possible to obtain highest Q for Parallel Resonance Circuit.
    The conductor thickness has less importance compare to conductor quality due to RF Current Nature.Because RF Currents flow vicinity of Outer Part of the Conductor so -for instance- using a Silver Plated copper wire will be better than simple copper.In old days, Transmitter Coils were made with Silver Plated Copper Tubes..


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  3. #3
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    Re: Tuning Selectivity Factor

    The ratio of L:C plays a big part in performance. It's not necessarily easy to calculate what ratio is optimum in your application.

    Ohmic resistance has an effect on Q. Higher resistance causes lower Q.



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