Biran : I downloaded the program and I entered the values of my measured inductor Leq= 21.2 michoH , this is very good result. I suppose the Resistance would be computed via skin effect. For any reason looks like includes the parasite capacitance, this is ok if you want to compute the parallel capacitor for a trap for example or if you with to use the inductor on a circuit design ( for this reason I assigned it to (Leq)uivalent).
L varies on frequency if you see it goes up this is because you have Cp in parallel then que equivalent Leq= L1/(1- Omega^2 L1 Cp) , L1 is the pure self inductance. Q is ok ! Freq/SRF measured is 0,17 and this is also good.

The Q mismatch you mention comes from this error in my opinion , I would need to verify via calculus… but if you read my post you will see that Q goes down if I consider Cp the capacitor used on trap also reduces Q.

This is a very good program!!

In this example (I posted a capture) I set 2.7 MHz as reference Leq= 21.2 microH , the capacitor to made a trap is C= 163.9 pF we can approximate Cp = 2.81 pF (this is using the program F/SRF ratio) , L= 20,84 microH then If we ignore Cp Q= 169.8 with Cp Q= 166,75. I recommend to perform this calculus and check because in the most of cases the coil Q defines the resonator Q . In my measurement the capacitor Q is ~ 20 times the inductor … you can see when I measured C ESR= 0,13 Ohm… this is not perfect but Q functions like parallel resistors … Qtrap= QL QC/(QL+QC) then Qtrap will go down by 5%

Other source of error is because Cp is in general a very bad capacitor , in general results of form dielectric constant and wire enamel… with the most of energy in a lossy capacitor Q goes down… it also affects the self resonance frequency measurement because the dielectric constants varies with frequency for this reason there are another method to compute Cp at the work frequency I shown it in other post.

Of course you have optimum values for higher Q it depends on wire length and geometry.




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