Wouldn't it be easier to look up the Part Number in the Catalog ??
73, Dick, W1KSZ
> From: pfizenmayer2@q.com
> To: larry@w7iuv.com; amps@contesting.com
> Date: Wed, 31 Mar 2010 15:30:39 -0700
> Subject: Re: [Amps] LCR meter & measuring components
>
> FWIW - There is a pretty definitive method of measuring an inductor which
> will
> yield its low freq inductance , its self resonant frequency , and the
> distributed capacitance.
>
> It is normally done with a Q meter but can be done with any instrument with
> variable freq below the self resoannt freq that will show what capacitance
> is required to resonate that inductor at that frequency.
>
> Just measure capacitance to resonate at several freqs well below the self
> resonant freq - theoretically two freqs will do but I prefer three or four
> as a check that nothing screwy is going on .
>
> Then plot C to resonate on the vertical scale and plot 1/f squared on the
> horizontal axis. The points will (or should) fall in a straight line. If
> not , an average thru the points will get you very close. The line will
> intersect the vertical axis and that point is the distributed capacitance.
> The intersection with the horizontal axis is the self resonant frequency
> (zero external capacitance to resonate)
>
> The slope of the line is the low frequency or "true" inductance.
>
> Dunno if I can do this equation but here goes.
>
> Basically you take a region of the sloped line and read off a change in 1/(f
> squared) for a change in capacitance to resonate (Delta 1/F^2) and (Delta
> C)
>
> Then L is 1 /(4 pi squared X Delta C / Delta 1/F^2).
>
> Or , if you want to know the "apparent" inductance at any frequency then
> read off C to resonate at that frequency , and using the Co or distributed
> capacitance at the intercept the L apparent is L(1+ Co/C)
>
>
> If you just want the self capacitance - two frequencies , one twice the
> other - F1 (C1 to resonate ) and 2F1(C2 to resonate) can be used to
> calculate
> self capacitance = (C1-4C2)/3 .
>
> If I still had my web site I could put this on it but Qwest in their
> infinite customer service wisdom dropped us .
>
> Ancient ancient history when we did not have all the fancy instruments of
> today .
>
> Hank K7HP
>
>
>
>
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