I am guessing that Bob is talking about insulated wire on the ground. But
some specifics from him would be useful.
Frequently mentioned specific radial implementations, in no specific order:
1) Raised radials
2) Radials of insulated wire laying on ground or embedded in lawns, etc.
3) Bare wire on, or in the ground.
I suspect, but do not know that he is referring to 2). 1) would not be an
issue as everyone treats these as needing attention to resonance issues. 3)
in reasonably conductive ground, together with very fuzzied velocity factor
issues, the radials can be part of a far reaching ground of many
wavelengths, whose appearance of any resonance can be anywhere between
non-existent and mild. Buried radials are as grounded as the "ground"
permits.
2) will have significant modification by velocity factor issues, which have
been *measured* anywhere between 45 and 85 percent. The actual distance
from the conductive earth is highly variable in individual installations,
as is the nature of the earth itself.
Anything laying on the ground is severely modified by velocity factor. If
he is talking about very dense radials, ~60 plus, the capacity at and near
the ends to earth of all the wires is quite high and can easily blunt
resonance effects, depending on ground conductivity.
>I posted this on TowerTalk and I got a couple of responses as to why
> >the ends of ground radials should not be grounded.
> Isn't it dependent on whether you want the radials resonant or not? And
> if you do want them resonant, on the length of the radial?
> It doesn't make sense to ground the far end of a quarter wave radial if
> you want a low impedance at the base of the antenna. It does make sense if
> you have short radials and want to intercept the "return current".
> Bob VE7BS
>
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