On Tue, 4 Mar 2008 05:29:08 -0800, W7TMT wrote:
>I seem to also remember another post where someone (Tom perhaps? - I don't
>remember now) said they had talked with Orr about this configuration and he
>later agreed that perhaps it didn't work as stated in the book.
If you can hoist a wire (or that twinlead) to the height you've described,
the best way to utilize it is as a top-loaded vertical Tee. Simply tie both
sides of that feedline together at the ground and feed it against radials.
Tweak the length of the top horizontal section to bring the vertical to
resonance. That will give you something on the order of 30-35 ohms at the
feedpoint.
Or, even better, simply make the horizontal section longer until the
feedpoint is 50 + jxxx ohms, and add a capacitor in series at the base to
tune out the jxxx ohms. I'm doing that here, and it works well. The vertical
is about 86 ft, the horizontal is about 70 ft, and the cap is 350 pF. This
centers it at 1825 kHz. These values will vary a bit depending on your
terrain (mine slopes) and the resistance in your radial system.
73,
Jim Brown K9YC
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