snip > The Antenna Compendium describes some experiments with the
"Half-Loop" antenna which is a half of a full loop
> antenna fed against a ground screen.
> I have had good luck with full-wave loops in the past, but
> height and size have prevented trying such on 80m or 160m.
> I am curious if anyone has experience with this type of antenna?
This configuration is often referred to as a "travelling wave" antenna and
the results can be quite good. I used this type for a few years 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. 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. It
performed very much as a Rhombic I later installed.
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 are in the ARRL Antenna book.
Only caveat. . . in Florida it was very susceptible to induced voltages from
nearby lightning so protect your rig.
> 73, Brian
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Administrative requests: towertalk-REQUEST@contesting.com