Maurizio Panicara [mailto:i4jmy@iol.it] wrote:
> Did anyone tried anything like this but scaled on 160m ?
> http://www.star-h.com/publications/ieee2002.pdf
Yes, I have been using a system somewhat similar to this for nearly 20 years
on 160. In my case the array consists of three verticals, each about 0.1
wavelengths tall, in a triangular configuration with spacing of about 10m.
Each vertical uses a combination of top loading and bottom loading. Each
vertical by itself has a feedpoint resistance (both predicted by modeling
and confirmed by measurement) of about 5 ohms. In the array, the resistance
increases to 15 ohms, exactly as this article predicts.
I think the main advantages of this approach are purely practical
ones--reduced height and easier impedance matching because of the higher
feedpoint resistance. I use a simple L-network at the junction of the
feedlines. Theoretically, with zero loss, there is no real performance
advantage for this system over any short vertical system that also has zero
loss.
73, John W1FV
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