I suspect your data. For a 0.1 lambda vertical, the radiation resistance will
be quite low particularly with sloping loading wires and with your radial system
the ground loss will be high. Additionally, I think the top loading is
insufficient to achieve resonance. Yet you seem to have it. Your feedpoint Z
is 15 ohm which seems too low, yet your SWR curve is too broad. Something just
looks funny to me, but I've been wrong before.
Wes N7WS
On 9/18/2018 1:44 PM, Ashraf Chaabane wrote:
Hi all,
I just finished setting up my vertical antenna for 160 in 3V8SF location. It
is 17m (55 ft) long with 2 top loading wires 12m each (40ft), angle to
vertical about 40 deg. I added 8 radials, 20m each (65ft).
With no shunt matching, the SWR at antenna base is 3.2 and at radio side is
2.8. Is there any way I can improve the SWR further?
Photos of the antenna along with SWR curve can be found here:
https://drive.google.com/drive/folders/1_3FsWZI3zdi56zz0LOiKNOmfgiWeN6yG?usp=sharing
73 Ash 3V8SS/KF5EYY
www.kf5eyy.info
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