[Elecraft] dipole antenna efficiency

[David Cutter]

I made this system primarily for its mechanical properties.  I will make 
some measurements one fine day....

David
G3UNA


----- Original Message ----- 
From: "Bob Cunnings" <bob.cunnings at gmail.com>
To: <elecraft at mailman.qth.net>
Sent: Sunday, January 06, 2008 11:06 PM
Subject: Re: [Elecraft] dipole antenna efficiency


> The capacitance between individual strands in Litz wire limits it's
> usefulness above 1 MHz or so. W8JI has an interesting discussion of
> skin effect at:
>
> http://www.w8ji.com/skindepth.htm
>
> Bob NW8L
>
> On Jan 6, 2008 3:54 PM, David Cutter <d.cutter at ntlworld.com> wrote:
>> I've used several strands of enamelled copper wire twisted together.  I
>> usually twist 3 sets of 3 of quite thin wire, whatever is on hand; 0.2 to
>> 0.45mm dia is easy to use; after twisting I give the group a good pull 
>> the
>> stretch and stiffen it a bit but it still remains very flexible indeed 
>> and
>> does not have a memory effect.  I tie the wires to a fence post then fit 
>> the
>> other ends into an electric hand drill 25m, it's surprising how much
>> twisting is needed. You must not let the wires touch the ground.   It is
>> also very slippery and does not cling to other wires which I find a great
>> advantage when manipulating multi-wire structures.  I call it "multi 
>> twist".
>>
>> David
>> G3UNA
>>
>> > An "El Cheapo" approach might be to use multi-conductor cable
>> > instead of a single, fat conductor to minimize Skin Effect losses.
>> >
>>
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