> I feel kind of obligated to respond to the question regarding "450" ohm
> "window" type ladder line, since we are responsible for some of the
> error. The earlier models were solid, 19% copper clad steel. We insisted
> on 30 %and a better polyethylene jacket, and supplied the wire for a
> stranded 18 gauge model as well, which was actually 40% -as a pilot run.
> The stranded was so successful that we contracted for a 16 gauge model in
> reworked dies, and a bit later, 14 gauge. The only way that the MFR could
> see their way to do this on a relatively low volume operation was to use
> the same machinery for all of them, modifying only the extrusion orifices
> - not the width set. Obviously, then, as the wire gauge got larger the
> error from the original years ago design at 450 ohms, nominal, increased
> downward.
> Press Jones, N8UG, The Wireman, Inc., Landrum, SC, 29356
So, if I understand this correctly, the 14 gauge, nominally 450 ohm line
that I bought is actually something other than 450 ohms; and rather than
being less sensitive to environmental conditions (the reason other than
physical strength that I bought the heaviest) it is more sensitive?
So if it is carrying ice, in a heavy rainstorm, exposed to ash or other
pollution, it is likely to underperform relative to the 18 gauge 450 line?
Please clarify. It is helpful to know when odd tuning circumstances occur
where the likely source might be found (e.g. when the line is iced or it is
raining or snowing heavily here in New England I should probably expect it
to behave badly).
Seems this is a week for clarifications and "confessions" from
manufacturers here on TowerTalk ... kinda of good that manufacturers feel
"safe" to do that here! Now, if this could only be an example to some of
our elected officials ... ooops, off topic! :-)
Thanks & 73, DavidC AA1FA
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