On 1/7/2022 6:14 AM, Pete Smith N4ZR wrote:
is the size of wire used for on-the-ground radials - or elevated radials
for that matter - significant?
The only significance is their mechanical characteristics to withstand
physical conditions.
> at least as compared to feeding the antenna against a single ground
> rod.
The earth is a big resistor. We do NOT want a connection to it, except
for lightning protection. Indeed, radials have two functions -- to
provide a low resistance path for the antenna's return current, and to
SHIELD the antenna's field from the lossy earth.
The only antennas whose performance benefit from an earth connection are
receiving antennas.
Conversations here can point us to consider other options, but are not a
substitute for serious study of fundamentals. Real understanding of how
stuff works is better obtained by study of the Handbook, the Antenna
Book, and the ON4UN book.
Rudy Severns, N6LF, has done a LOT of excellent work, in the form of
interactive modeling concepts, building and measuring radial systems,
modeling some more, and building measuring some more, then publishing
what he's done and what he's learned. It's also well worth studying.
https://www.antennasbyn6lf.com/ Going to his site to find this link, I
see that since my last visit, he's published some work on loop and loop
on ground RX antennas.
Almost ten years ago, I summarized what I'd learned from others on the
topic of 160M antenna systems for limited space in a talk I've done at
Visalia, Pacificon, and for several clubs including NCCC. Most of it is
about radial and counterpoise systems. None of it is original work on my
part. The slides are here. https://www.antennasbyn6lf.com/
73, Jim K9YC
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