Tom notes:
> Also Hams tend to think in terms of too many radials. Things
> get really flat after 50 radials.
>
> The most surprising thing I learned is how little base
> impedance actually means when guessing efficiency.
>
> 73 Tom
After spending hours studying the graphs 9-14 through 9-19 in ON4UN's 4th ed, I
fail to understand the significance if all the hoopla regarding the so-called
"perfect" ground system. What you want is a ground that works. For example,
in fig 9-19 (80M), going from 32 - 40M radials gets you a whopping 0.31dB of
gain over 8 radials of the same length. In a very few QSOs during a ham's
lifetime, this may matter. In 99.9% of the QSOs, I seriously doubt that the
extra 1000M of wire will matter. Lay down what you have the time, the space,
the $$$, and energy to lay. Feel confident that you are good-to-go Top 10 if
you have the rest of the skill set to get you there. My gut feel for the topic
indicates that elevated radials vs grounded radials must be viewed in the same
light. If the quest is perfection, well, then that's different. If the quest
is effectiveness, then a different set of criteria will likely apply.
Tom, heretofore, a buried radial system under 1/4wL vertical was evaluated
based on how close the actual impedance was to the 36 ohm R of the classic
monopole. If I understand your last comment correctly, you indicate that the R
value fails to predict field strength? Can you describe what you mean? Or
better yet, what you are observing? Possibly more importantly, how you
measured it?
Ford-N0FP
ford@cmgate.com
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