May not have been the best example, but the point is that depending on the
antenna, resonance and 50 ohms do not always coincide and that some form of
matching is required.
The lower impedances may have been from shortened verticals as studied by
Sevick.
A better example might have been a 5/8-wave, they're what, about 120 ohms? If
you try to adjust the length of a 5/8 wave to get a pure 50-ohm non-reactive
load, you won't have a 5/8-wave anymore.
The impedance of a end-fed 1/2-wave won't be anywhere close to 50 ohms, either,
will it?
73, Kelly
ve4xt
Sent from my iPad
> On May 4, 2014, at 8:58 AM, "Peter Voelpel" <dj7ww@t-online.de> wrote:
>
> A lossless quarter-wave monopole has an radiation resistance of 35 ohms.
> To that all losses will be added and the result is the feed point impedance.
> That will never have an impedance of 12 ohms but 40-50 ohms or more.
>
> 73
> Peter
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Kelly
> Taylor
>
> A resonant quarter-wave monopole over a decent ground might have an
> impedance of about 12 ohms.
>
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