Did you open up a Cushcraft balun to discover that method? I believe some
other companies do similar and Teflon wire is used so it doesnt char as does
THNN.
Carl
KM1H
----- Original Message -----
From: "Jim Brown" <jim@audiosystemsgroup.com>
To: <topband@contesting.com>
Sent: Tuesday, August 30, 2011 10:33 AM
Subject: Re: Topband: Fabricated common mode chokes - Sourcing
>A year or two ago, based on the experience of some hams in the UK who
> found Fair-Rite cores either impossible to obtain or very expensive, I
> did some more experimental work that resulted in designs for
> transmitting chokes that can be wound on a single #31 core, be very
> effective from 80-10M, and handle at least 500W with antennas that have
> reasonably good balance. If the antenna is well balanced the choke can
> handle legal power.
>
> The new designs use bifilar windings -- that is, two conductors taped
> together and wound around the core that function as a parallel wire
> transmission line in place of coax. An alternative design uses more
> turns and covers 160-15M. These designs were added to my RFI tutorial
> last summer (June 2010). The best of these designs use ordinary "house
> wire", known in North America as THHN.
>
> The tutorial is http://audiosystemsgroup.com/RFI-Ham.pdf
>
> 73, Jim Brown K9YC
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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