*I highly doubt that my little 450 Ohm Windowed Line, will ever be used at
12.5Kw. For an ERP of 20.5Kw like KFBK. My 80 Meter Dipole however works
just great with the 450 ohm line and a good Tuner. We can cover 80 through
6 Meters with decent results. The other option would be an ugly Fan Dipole
or the use of Traps along the antenna's length. Neither of those seem very
appealing to me. My SB-220 hasn't killed the first bird yet. *
* 73 from Wade/KJWS*
On Mon, Oct 19, 2015 at 4:51 PM, Rob Atkinson <ranchorobbo@gmail.com> wrote:
> >Re-read my sentence. I am not objecting to the use of open wire line when
> it is matched to the antenna, but to the use of it as a band-aid for badly
> matched antennas.
>
> I suppose it gets down to the meaning of "badly matched." If by that
> you mean for example a 1/4 wave dipole fed in the center then I'd say
> nothing should feed such a load because it's pretty close to hopeless.
> This is an antenna that will probably have an impedance of just a few
> ohms. I have heard of hams building balanced matching networks
> capable of handling 20 or 30 amps for such an antenna but I'd put up a
> bigger antenna.
>
> Most all medium wave broadcast stations have abandoned their open wire
> unbalanced line. KFBK in Sacramento still has it as far as I know.
> They may be the last. That line worked okay in the days of tube rigs
> but the solid state boxes would kick off if a bird flew into the line
> and got across the center and one of the outer lines. they had to go
> to coax below grade. I am not against coax; I use it with unbalanced
> loads.
>
> 73
>
> Rob
> K5UJ
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>
--
*Living one day at a time with Jesus as my Savior. But, still having Fun.*
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