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October 11th 03, 03:16 AM

On 4 Oct 2003 16:42:36 -0700, (Walter)
wrote:

(1) Will using a Ladder Line instead of Coax improve my reception?

For really long runs maybe. The biggest advantage for ladder line is
its low loss. But with 500 feet of longwire, you have plenty of signal
which would easily overcome any appreciable loss.

I researched this myself recently. Some say it wouldnt hold up to
rough weather such as snow and ice. Coax is pretty rugged comparably.

The key to using coax effectively is ensuring you're matching the coax
to the antenna. Given the longwire might be 450 ohms or better a 4-1
or higher balun (actually called a long wire matching transformer) is
imperative.

If your improperly matched, 75 ohm coax is better than 50 ohm as it
would reduce the mismatch slightly.

To ensure the coax actually helps block noise as it feeds the signal
in, be certain to ground the sheild at both the antenna and near the
receiver. If you dont do this, currents flow in the shield.

While coax is marginally lossy, improperly matched coax is really
lossy. When the antenna and coax are matched you get max signal "flow"
to your receiver.

(2) If so, where do I change to coax? Or do I just run the Ladder line
into the house and straight to the receiver?

I think you would need a balanced/unbalanced (balun) to do this.
Ladder line is balanced, coax is not.

(3) What about electrical interference since the ladder line isn't
shielded?

Ladder line cancels noise like twisted pair does. Each wire cancels
the noise picked up by the other.

Lastly, consider an antenna tuner if you dont already have one, this
will further help in matching as impedances change with frequency.

mike

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