On Tue, 25 Feb 1997 11:59:52 -0500 (EST) W8JITom@aol.com writes:
SNIP
>
>Conductor spacing and balance to ground along the antenna is critical.
>Simply grounding one wire at the far end almost gurantees poor
>performance, as does a transformer with improper design.
>The antenna itself should use wires spaced as close as possible, and
>hopefully have a Zo matching the reflection transformers design
impedance. A
properly designed system will have no impedance mismatces, and near
perfect
balance. That's why I use 450 ohm line twisting it along it's length, and
use
well designed transformers at BOTH ends.
>I've never had a system that was not repeatable, in Sylvania Ohio over
>wet balck marsh, in South Amherst Ohio over midwest clay, and in
>Georgia over rocky poor soil they all worked the same.
>When NI8G duplicated my system exactly, he obtained the same results.
>
>73,
>Tom
All good information but certainly not in the realm of the popular press.
Maybe Tom would like to share the FULL design info, including the
transformers. Then we would all have a chance to build and evaluate.
I and others have been using the 12" to 18" spacing as recommended in
those pubs you have to pay money for. If I can trade in my runs of #12
Copperweld for some cheap 450 Ohm ladder line, I certainly want to hear
about it.
Meanwhile the Slinky system that I use as an alternative to full size
Beverages continues to amaze me. P29VXX was not reliably copyable on any
wire Beverage but was Q5 on a Slinky for 40 minutes. The regular
Beverages were vy noisy this AM and it was the S/N ratio that made the
difference with the Slinky. Some days it is just the reverse.
73........Carl KM1H
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