On Sun, 08 Aug 2010 10:25:05 -0500, Dr. Gerald N. Johnson wrote:
>And the
>distributors rate only on permeability, getting that resistive data
>takes extra legwork, sometimes lots of extra work.
You should visit the Fair-Rite website. That is NOT true of them. The
front of the catalog (15MB as a pdf) shows plots of u' and u'' vs
frequency for every material. The rest of the catalog consists of data
sheets for every product designed for suppression, there are plots of
impedance magnitude vs frequency, and of series R and X vs frequency, for
one turn, two turns, and three turns.
>Most times I wish reactive isolation not to waste power in resistive
>isolation.
That's another hole in your understanding of how things work. You would
benefit from reading my tutorial on coaxial chokes. Dissipation can be
made quite small if you make R large enough, and, as it turns out, it's
easy (and inexpensive) to do that if you understand the materials.
http://audiosystemsgroup.com/RFI-Ham.pdf
It should be noted that understandings articulated in that tutorial are
the result of years of research and study. Last winter, someone forwarded
to me a D.O.D. report that came to virtually all of the same conclusions
c.a. 1966, but not made public at the time.
73, Jim Brown K9YC
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