At 09:10 PM 3/18/02 -0500, David L. Thompson wrote:
>Sounds like the K8UR array described by K3LR and others over the past few
>years. I use one K8UR dipole for 80 that seems to get the DX. Down on most
>local signals. Mine is mounted on a big tree but a tower can be used. An
>array of 4 would work well as noted. But remember like the 4 square these
>are arrays of 2 phased antennas. The K8UR looks like a vertical when
>modeled.
Actually not... the W9LT/K3LR design (K3LR wrote it up for QST, but I
learned about it from W9LT, who thought it up 30+ years ago) uses 4
"lazy-vee" dipoles, with one driven and three used as parasitic reflectors,
induxctively loaded in their centers by ~150 electrical degrees of
feedline. The switch box floats both shield and center connector of the
unused dipoles feeders to achieve this.
The success of the antenna is to some degree dependent on the presence of
the tower, at least to judge by the current present on it. Another
interesting angle is that when cut for CW, the antenna continues to work
well up in the phone segment, but the converse is not true. Much below its
resonant frequency it becomes essentially omnidirectional.
73, Pete N4ZR
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