Topband: Loss comparison between two antennas

[Jim Brown]

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