> M2, Raibeam, Antenna Mart and many others deserve your business who sell
> great products and I'd support them. New and effective designs are bad
> mouthed for long periods of time until competent evaluators give it a
> clean bill of health. Large sums of money and time can be invested in a
> new product and killed or sales crippled by the "Army of the Performance
> Misinformed" and does a lot of damage unfortunately without recourse.
There certainly is a lot of unusual antenna science!
One antenna manufacturer, in a QST article, claimed or implied the
ionosphere does not respond in a reasonably linear way to system
gain. Besides implying a grossly non-linear ionosphere, they
"cooked down" performance of other antennas in a graph or
comparison chart.
Another manufacturer claimed more gain than is possible with any
combination of spacing and phasing using two elements. They
"invented" a thing called "critical coupling K=1" to explain how they
could have gain beyond theoretical limits of a perfectly excited and
spaced lossless structure.
When asked to check out a 40 meter quad for a friend of mine, I
asked about gain. The salesman/ designer told me when a dipole
at the same height would be S-8 the quad was 20 over 9 in New
Zealand. I thanked him and advised my friend to buy something
else, because I couldn't get a straight answer.
The common excuse is there is something "special" going on that
just can't be explained, and that models won't even show how well
the antenna really works. That's a warning sign of pathological
science at work!
73, Tom W8JI
W8JI@contesting.com
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