This configuration is often referred to as a "travelling wave" antenna and
the results can be quite good. I used this type with a matching unit at the
ground feedpoint which also included several ground radials. The apex was
at 80 feet in a tall pine and the other end I terminated with a 50 ohm
resistive load into a long ground rod with again several random radials.
The SWR is of course 1:1 on all bands since any reflected power is simply
dissipated into the far ground.
This antenna was about 580 feet long in my backyard (had 3 1/2 acres) and
was HIGHLY directive! Since it operated as several wavelengths on the
higher bands it performed very much as a Rhombic I later installed. I
would often work East Europeans with very strong signal reports and they
often commented that I was one of the stronger signals out of the SE US
especially during the opening and closing of the bands.
I also constructed a smaller version that was only 130 feet long and it
worked quite well. It was also a very quiet antenna. The instructions for
this antenna is in the ARRL Antenna book.
Jon, W4ZW
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