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Re: Topband: multicore phone cable as radials

To: "jonathan white" <jonathang8ccl@gmail.com>, <topband@contesting.com>
Subject: Re: Topband: multicore phone cable as radials
From: "Tom W8JI" <w8ji@w8ji.com>
Reply-to: Tom W8JI <w8ji@w8ji.com>
Date: Mon, 23 Jul 2012 10:29:47 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
> Idea is each individual strand in the cable will act as one radial.
> BUT I probable know the answer.

Unfortunately there is no magic. The objective of a radial is spread the 
electric and magnetic fields out, so they are not as intense. The only real 
solution is to fill a large physical area of space in terms of the 
fractional wavelength, like maybe 1/4 to 1/2 wave of physical space in every 
direction possible.

This means we can fold a radial or pack radials in a group, and we still 
have whatever linear space that system occupies. It is very similar to an 
antenna, where packing 5000 feet of wire in a small one foot box results in 
a one foot area antenna. There just isn't any magic by any amount of folding 
or grouping, we still have the same area in wavelengths.

We can do things to change reactance and change voltage and current 
distribution, but in the grand scheme of things it effectively remains the 
same linear spatial area or LESS.

The entire cable acts as one radial. If it was .1 wavelengths long 
physically and wired to fold the wires back and forth, it would still be .1 
wavelengths long.

If it had all the wires in parallel at the start end or both ends, it would 
still act like one wire.  As a matter of fact if in parallel, all the wires 
inside the bundle would electrically just vanish and not carry any current, 
like the core wires of a stranded conductor. You can make it act like a stub 
and change reactance, but it won't ever get electrically bigger as a radial, 
just like folding wires in an antenna does not make it couple to space 
better.

73 Tom 

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