[Antennas] Classic 20 meter Endfed Zepp

Fri Dec 9 22:13:31 EST 2016

On 12/9/2016 7:06 AM, Niel - W0VLZ wrote:
> Does anyone else tried a 20 meter End Fed Half Wave wire fed with a 1/4
> wavelength of TV twinlead (Classic 20 meter Endfed Zepp)? I've used one

The fundamental problem with this discussion is that it focuses
on impedance matching, which it would do an OK job of, except
that the line is being operated in an unbalanced mode and therefore
will radiate AND will not do a proper impedance match.
It would, in theory, work if you replaced the twin lead with 300 ohm 
coax, which alas does not exist. It would also work if you could
put common mode chokes are both ends, but they are impractical for
such a high impedance.
The antenna will still radiate if you have a tuner that can tune it.
But it may be nowhere near 50 ohms.
It is fairly easy to match a 1/2 wave using around 2 uH and around
5O pF in an LC match.
Rick N6RK