On 7/8/2012 7:54 AM, Steve Flood wrote:
> This resonates the antenna below 1.8Mhz with a feedpoint
> Z of 37 +j245. Matching is through an L-network. My intention was to
> increase radiation resistance and efficiency and move the current maxima
> away from the feedpoint and to the center of the vertical for lower takeoff
> angle.
About five years ago, I increased the top-loading on my 86 ft Tee
vertical so that the feedpoint impedance was 50 + J xxx, and tuned it
with series capacitance. It works "well," but there's no good way to
compare it to anything, other than, perhaps, a model. Like you, I have
a lot of radials on the ground. A couple of years ago, I added a second
vertical wire, spaced from the first by 6-8 inches, wired in parallel at
both ends. The second conductor increases the SWR bandwidth nicely.
73, Jim K9YC
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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