What may be more destructive is a slow velocity factor in the insulated
wire. There is no way to estimate that, you just have to measure it. If
the VF is low, then you get into the same kind of problems as one has in
designing BOG's (beverage on ground), where the signal already on the wire
is moving much slower than the signal in the air, just about to induce the
wire.
Telco C wire was not designed with anything RF in mind. The dielectric
might be something exotic specifically designed for long life, and a VF
slow as molasses.
73, Guy.
On Mon, Jul 23, 2012 at 9:32 PM, ZR <zr@jeremy.mv.com> wrote:
>
> ----- Original Message -----
> From: "Bruce" <k1fz@myfairpoint.net>
> To: <topband@contesting.com>
> Sent: Monday, July 23, 2012 3:56 PM
> Subject: Topband: Beverage antennas
>
>
> >
> >
> >
> > Re Tom:
> > An impedance error of 20 ohms on a 100 ohm line is as meaningful as an 80
> > ohm error on 400 ohm line
> >
> > Thanks Tom for clearing that up. I tried early Saturday morning, while
> > very sleepy, to get this info out. A 680 ohm line Beverage with fence
> > wire, the error ratio is even higher.
> > (Wide spacing is more RF forgiving, in terms of inches, than close spaced
> > lines). But we do need to be accurate.
>
>
> ** Wide spacing is also more prone to unbalance wheras close spacing and
> twisting promotes good balance.
>
>
> > A few years ago I had customer reports, stating they had run their two
> > wire, fence wire Beverages, fastened vertical with good results. At that
> > time I switched a 300 foot horizontal run to vertical, and could not see
> > any difference. Granted this was not an instant change A to B test, but
> > it sure is an easier installation. I haven't seen anyone frequently
> > transpose their two fence wire Beverages in my area, but may be a good
> > idea.
> >
> > 73
> > Bruce
>
>
> ** That barely qualifies as a subjective test and 300' for Topband isnt
> that
> directive/effective to start with.Try it at 1 wavelength or more in a
> controlled test.
> Carl
> KM1H
>
>
>
>
>
> > No virus found in this message.
> > Checked by AVG - www.avg.com
> > Version: 10.0.1424 / Virus Database: 2437/5149 - Release Date: 07/23/12
> >
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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