I generally agree with you, Bob - especially with regard to not grounding
the far ends of 1/4 wave radials!! After all what we are trying to
establish is a low-impedance "image plane" for the vertical radiator to be
fed against! A 1/4 wave wire, grounded at the far end would have a high
impedance to ground at the base, or feed-point, of the antenna! Makes no
sense! Would not result in a very favorable "driving-point impedance!
The issue is complicated by the number of radials, the soil, and the radial
length.
Even buried radials directly in contact with soil are "resonant", the extent
of which depends on the shallow and deep characteristics of the earth. In
most soils, bare wires are not grounded for RF as well as people probably
think.
Measuring buried 40 meter radials here, I could get a fairly high base
impedance with some radial lengths and numbers. This did **not** affect the
field strength. With about a dozen radials the base impedance of a 40M
vertical with long radials was about 50-60 ohms. It had about the same
measured field strength as 4 elevated resonant radials that had a base
impedance down in the upper 30 ohm range.
People used to use ground rods at the ends of radials when they had to
truncate the radials. Also, some people used ground rods and no radials at
all. They swore by those systems, wrote articles about those systems, and
even bragged about all the DX they worked.
Opinions, contacts, or feelings tells us more about how difficult it is to
tell how well something really works than it tells us how the systems
actually work. That's why this stuff rages on and on for decades.
Even the AM BC stuff was mostly meaningless nonsense. People would pull
radials in over other radials while guessing not many of the old radials
were still there, make measurements with 3 dB of wobble in the readings and
pick the numbers they liked, and call it conclusive evidence.
73 Tom
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