[Elecraft] Home made Sigma-GT5 & KRC2 or SGC?

[Stuart Rohre]

120 in ground radials are a standard for AM BC stations only because of the
influence of Brown's original papers on the then FCC.   It is said Brown
actually doubled the number to 120 to cover possible errors in the limited
analysis and measurements they could make in the 1930's with the instruments
available then.

Most studies of radials in the Antenna Compendiums, Antenna books and texts
show that above 32 radials for Short wave use, there is convergence of the
results such that the extra work to go above 64 radials is not warranted for
Short waves, although there might be an effect at medium wave BC band.  Look
at the graphs in the Various ARRL and other texts that show clearly the
convergence as you increase the number of radials.   Hams can hardly expect
to see any difference with more than 32 radials in HF uses.  Actually, if
you balance the number of radials and current in each, you only need radials
in directions of ham activity, ie toward major continents and ham locations.
You don't care to increase your signal toward some unoccupied area of the
Indian ocean for example.

All radials in the earth are detuned by it and are lossy at best compared to
radials not surrounded by lossy earth.  The whole idea of a radial is to
replace earth and improve conductivity.  The burial seems contra to that
end.
73,
Stuart
K5KVH