Re: Finding 'mu' for magnetics

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Original poster: Harvey Norris <harvich-at-yahoo-dot-com> 



 > >My proposed method:
 > >
 > >1) Wind a coil on the core, measure the inductance.
 > >2) Take coil of core, measure inductance again.
 > >3) Calculate mu from ratio.
 > >
 > >Sounds too simple - but is it?
 > >
 > >Cheers
Make sure you use soft ferrites, the hard ones used in
magnetised ferrites actually have a very poor
permeability.  I think I only measured a doubling of
inductance by insertion of unmagnetised ceramic 8 core
into a coil.
HDN