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From: jeffw@midas.WR.TEK.COM (Jeff Winslow)
Newsgroups: sci.electronics,rec.ham-radio
Subject: Re: Litz wire (long)
Message-ID: <2243@wrgate.WR.TEK.COM>
Date: 12 Apr 90 22:35:08 GMT
References: <40251@iuvax.cs.indiana.edu> <28533@cup.portal.com> <3368@optilink.UUCP> <1990Apr12.071836.17112@monu6.cc.monash.oz>
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Reply-To: jeffw@midas.WR.TEK.COM (Jeff Winslow)
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Organization: Tektronix, Inc., Beaverton,  OR.
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In article <1990Apr12.071836.17112@monu6.cc.monash.oz> steve@monu6.cc.monash.oz (Steve Balogh) writes:

>The individual strands of wire in Litz wire are NOT insulated from each other.
>Litz wire is essentially LOTS AND LOTS   A N D   L O T S   of very fine (and
>sometimes silver-coated) wire all twisted together. Because of the greater
>surface area of such wire, it is supposed to have less impedance at RF
>frequencies than normal single strand wire.

Oh, really? And how can it have greater (electrical) surface area if all the
surfaces are in electrical contact? What keeps the current inside the fine
wires and away from the bundle's surface? (Especially if it's silver plated.)

Maybe usage varies in different parts of the world, but around here Litz wire
is most definitely made up of many fine wires all enamel-insulated from each
other, with each wire brought out to the surface periodically. I had a funny
feeling about this, due to some unanswered questions about proximity effect
(my experience with Litz wire has been limited to few experimental switching-
supply designs), so I looked it up in a couple of electronics dictionaries 
as well. They both indicated specifically that the wires are individually
insulated.

							Jeff Winslow