Reading the thread about an effective radial system got me thinking about the
pseudo-Brewster angle of a 1/4 wl vertical antenna. As strictly a
mental exercise, I
calculated how much radial wire would be needed for an 80m vertical Fresnel zone
that results in a low (1-2 degree) pseudo-Brewster angle. Assuming 120 radials
of 5 wavelengths each that comes to 30 miles of wire on a parcel of at
least 122 acres.
The tips of the radial will be 68 feet apart. This raises the question
is this too far
apart to affect the pseudo-Brewster angle? Devoldere says yes (Low-Band DXing,
3rd ed.). He says they need to be no more than .05 wl (13 feet) apart.
The return
currents will be nearly entirely collected by the close-in parts of
the radials. So
that's not an issue. John doesn't show the math or other analysis that
leads to the
.05 wl figure so I'm not entirely convinced it's needed. However, if
true, that would
require an additional 60 miles of wire.
Kris N5KM
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