Exactly how much is "a *lot* of loss", Jeremy? Too many knowledgeable
Topbanders have used it over the years --with great success-- for it to
have enough loss to matter.
Extra loss can even improve the F/B ratio! One famous Topbander (Earl
Cunningham, K6SE; SK) replaced his galvanized steel electric fence wire
with Copperweld. He soon took the Copperweld back down and replaced it with
the plated steel wire, because of that property. You can read all about
that here in the searchable Topband Archives.
I use that electric fence wire (probably cadmium plated) myself on my 580'
reversible Beverages. I don't need a preamp to bring up the noise floor,
and I doubt that is any different with the WD-1A.
I live in southwest Missouri, and there can be a lot of QRM and RFI from
the east coast on my NE-SW Beverage. Reverse it, though, and all that
disappears so we can copy VKs and ZLs to the SW. I'm convinced the extra
loss helps.
73, Mike
W0BTU
On Sun, Jan 12, 2020, 5:51 PM Jeremy Maris <jeremy@maris.plus.com> wrote:
> *Don’t* use the two conductors of a single run of twisted pair WD-1A as
> the transmission line - you’ll get a *lot* of loss in the transmission
> line. Instead parallel the two wires and run two lengths WD-1A (as Jim
> Garland says).
> 2 inches / 50mm spacing between them will give a line impedance of around
> 450 ohms, and much less loss.
>
> Jeremy G3XDK / G4AQG
>
>
> > On 12 Jan 2020, at 23:24, Herbert Schoenbohm <
> herbert.schoenbohm@gmail.com> wrote:
> >
> > Probably the most durable two conductor is Military WD-1A telephone
> cable.
> > available on eBay for $50 for about a half-mile. Special lower
> > impedance transformers are required to match the line's impedance. It is
> > also a great source for very durable single wire Beverages with both ends
> > connected together.
> >
> > Herb, KV4FZ
>
>
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