Hi Barry,
> make installation a lot easier if I could scrounge up the wire. If there
> is a technical down side to using such closely spaced conductors, I'd
> appreciate hearing from any knowledgable folks.
I've used 450 ohm line for all my two wire Beverages since the early
70's. For me, the extra cost is offset by the ease of construction.
There are no electrical disadvantages when using close spaced
wires, other than some slight deterioration of termination in wet
weather with plastic "ladder line".
As a matter of fact, I don't believe there are any real advantages to
using modest or wide spaced conductors in two-wire Beverages.
As a general rule, the closer and more evenly the wires are spaced
the better the antenna behaves. That's because it is easier to keep
the standing waves off the line, making termination better over a
wider frequency range.
Think of the wire as serving two functions, as an antenna with the
wires tied in parallel and as a transmission line to reach the far
end. Anyone who understands transmission lines would never use
a very long, wide-spaced, line (more than a few thousandths of a
wavelength spacing) because they know it would be a very poor
transmission line. The longer the line the more critical the spacing
is.
73, Tom W8JI
w8ji@contesting.com
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