Jim M,
I remain to be convinced about the benefits of loop TX antennas.
If you have the choice of a tuned wire 15m long in total , or a 15m by 15m
loop, it is not
surprising that the latter is a better bet - it is a much bigger antenna,
after all.
Actually under 'ideal' site conditions such as an open field, free from the
effect of trees, and where a good ground system can be installed, the top
loaded vertical with similar overall dimensions beats the loop for radiation
efficiency by 6db on average. Typical residential sites, however, are
another story. In my home situation the same 6db favors the loop over the
vertical - even for a #12ga loop wire. Additionally, I have found the loop
is whole lot more rugged when it comes to extremes in wind, rain, ice and
snow. What makes 'looping' even more fun, at least for me, is that this
success stands in the face of so much negative text written about the TX
loop. Renowned authors of antenna textbooks often state that the small loop
(I.E.: <<1WL) is of little value for transmitting.
Bill A
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