In response to Lee's message...
The Handbook and Antenna Book both have tables of vertical radiation
patterns for dipoles at various heights (in terms of wavelengths) above
ground. Unfortunately, below 1/2 wavelength the patterns show an awful lot
of high-angle radiation and not much at DX angles. I think it's fair to
say that whether a low dipole is better than a short vertical depends on
what you want to do, the trade-off between ground reflection gain and the
pattern shape, and how effective the ground plane under the vertical is.
One of the neat parts of fooling with antennas is that you can never tell
what that random swingset or telephone wire is going to do, either for or
against you. I'm not knocking optimum installations, mind you, but I spent
22+ years in a townhouse, with stealth antennas. For years I used inverted
vees tucked back in the trees -- 40, 20 and 10 meters coax fed off a common
feedpoint, at about 35 feet. On the ends of the 40-meter elements I had
lumped inductances (was this W9INN's idea?) that effectively isolated the
elements on 40 and loaded them to resonance on 80. Narrow-band, but worked
fine on the CW end. Used the 40-meter dipole on 15, too. Got 5BDXCC, even
if it took 2 solar cycles to do so.
Before that, we lived in a garden apartment below mean local ground level,
with a chain-link fence 10 feet away from the balcony and higher than we
were. Ran a Hustler mobile whip at 45 degrees off the balcony rail and
worked 120 countries in 18 months on 20. I always figured the fence must
have been reradiating my signal somehow.
73, Pete Smith N4ZR
In wild, wonderful, fairly rare WEST Virginia
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