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Re: Coupling Experiments



Hi all,
       On the df/F method of measuring k :

<snip>
> Could you explain again the df/F method for measuring k please? I have 
> tried using the difference in Lp with the secondary open and shorted but 
> I get gibberish answers. Now that I think about it, are you measuring the 
> resonant frequency difference with the secondary open and shorted?

This method yields a reasonably accurate figure below k = 0.15 or so.
Leave the secondary open circuit and get as far away from it as 
possible. Connect the scope across the closed (shorted gap) primary
circuit (e.g. across Cp). Connect the sig. gen. with a resistor of 
>10k in series across the cap. Tune the generator from below fr to
above. You'll see 2 definite peaks. Note the two frequencies, then
tune for an accurate null between them. This value is the system Fr.

k = (Fhi-Flo)/Fr

Malcolm