The good thing about large loops is they can have a
reasonable feed impedance on multiple bands since the low Z
point repeats at all harmonics, unlike a dipole where it
only repeats on odd harmonics. Other than that they actually
have little (if any) advantage.
> the diff is like 2 very different antennas. There is lots
of folklore about
> the "loop skyware" probably due to the gain it develops on
the higher
> frequencies
I certain agree with that assessment. Loops are a good
example of "feel good" antennas that are surrounded by
exaggeration and love. (If you think about it, there are
plenty of others around.)
The problem with a loop-skywire is the modest gain developed
on higher bands comes with a penalty of multiple
close-spaced nulls. Gain is actually generally undesirable
when it comes with narrow lobe peaks and multiple deep
close-spaced nulls near main lobes. Statistically we are as
likely to have a desired path fall into a narrow -15dB null
as into a narrow +5db peak.
On 75 meters, I did a comparison between a G5RV and a dipole
at the same height. When I would **say** the dipole was the
G5RV, it received worse reports than the actual G5RV I was
intentionally calling a "dipole". When I would call each by
the correct name, the dipole would win. When I would say
"antenna one" and "antenna two" and never tell the other
person which was which very few people could really tell any
difference between them. The modeled difference between the
two antennas was about 1 dB in favor of the dipole,
including matching and feedline losses.
Based on my 75 meter tests I think saying we are using a
"folded coaxial delta loop rhombic E-H fractal skywire"
would result in the best ragchew reports, as long as it was
really just an Inverted L with a good ground system.
How antennas make us feel is just as important as how they
work.
73 Tom
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