David Woolley wrote:
Craig D. Smith wrote:
Most everyone I know (including me) who uses the BuddiPole as a vertical
uses a single quarter wave elevated radial or counterpoise wire. This
costs
That could equally be viewed as being a quarter wave, horizontal antenna
with a vertical counterpoise. In free space, the longer of the two would
dominate. Over a good ground, things get more complicated, and I'm not
sure I can give a good intuitive analysis
Seemingly a quarter wave vertical with a quarter wave elevated horizontal
radial was a popular antenna amongst hams in the 1930s, and continued to
appear in the ARRL Antenna Handbook during the 1940s as the "Up and Out"
antenna. In those days the antenna was viewed as a halfwave centre fed
dipole with a 90 degree bend at the centre, although it was also used as a
multiband antenna I believe. But as you point out things are a bit more
complicated when the antenna is over ground. Without running a model, which
might not give accurate results, my instinct suggests that both the length
and angle of the 'horizontal radial' of a real single band antenna over
ground might have to be adjusted to obtain a non-reactive feedpoint
impedance for coax feeder - assuming that the vertical part is an electrical
quarter wave. During the 1930s and 1940s open wire feeders and antenna
matching units were of course the norm, which would probably make these
adjustments to the 'radial' unnecessary.
73,
Geoff
GM4ESD
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