Andy,
I used the "double-L" which, I agree, is really a bent vertical dipole
(BVD). After rewarding performance on 160m when hung from an 80-ft
tower with about 3-ft separation and the bottom leg about 6 ft above
(very poor) ground, I added an 80m element in parallel - the "double
double-L" or double BVD. I don't have many tall trees for supports so,
in contrast to K2KQ's recommendation to separate the legs of the
antennas as much as possible in azimuth, I was only able to separate
them by about 18 inches using PVC spreaders. According to a NEC2
model, the antennas are quite omnidirectional - much like the
inverted-L. - but the close spacing and parallel configuration
narrowed the bandwidth compared to legs separated in azimuth.
See also page 3 of the December 2009 YCCC Scuttlebutt for a picture of
the hole that one of the legs burned in the tree against which it
rubbed. Keep the high-voltage points away from flammable materials.
73 -- Brian K1LI
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Topband Reflector
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