Hi,
My recommendation wasn't regarding linear loaded elements. It was a
drooping element design. Half wave dipole elements, from the center
insulator outward the element is 1/8 wave horizontal and 1/8 wave
vertical. Invision a half sized quad element fed at the center. This
configuration isn't linear loading where the element is folded back upon
itself.
Model that one for me Yuri,
dave
wa3gin
K3BU@aol.com wrote:
In a message dated 11/5/03 10:16:22 AM Eastern Standard Time,
wa3gin@erols.com writes:
No. A properly designed lumped inductance is better than linear
loading. That's why many 80 meter Yagi owners have upgraded to
W6ANR's aftermarket loading inductors, replacing the original linear
loading. Linear loading is a marketing concept to make you think
you have eliminated the ohmic losses associated with loading
coils. Instead, it *increases* the losses.
Rick N6RK
<<
Amen and Ditto!
For those interested and willing to immerse in the "war" about the Current
Distribution in Antenna Loading Coils, significance on the efficiency of
antennas, problems with understanding and modeling vs. reality see my article and
some comments at
http://www.k3bu.us/loadingcoils.htm
The arguments are flying at the Newsgroup
rec.radio.amateur.antenna
in the thread
"Current in antenna loading coil controversy"
Original articles that started the "war" were on eHam.net by K0BG
The importance of this phenomena is that efficiency of loaded or shortened
antennas is roughly proportional to the area under the current distribution
curve along the element. Loading stubs or coils "eat" the portion of the current
curve and reduce the area/effciency. Top loading (T or L) "eats" just the tip
of the current curve, least area. T loading cancels out the "other"
polarization, L loading radiates it. The best application is in Moxon Rectangle, where it
provides also element coupling and fantastic F/B for two element antenna. The
current distribution in the loading coils has significant effect on the
design of loaded multielement beams, software so far cannot "stomach" it. ON4UN's
Low Band DXing has it right.
I don't want to start another war here, rather point to what was already
rehashed and with W9UCW and W5DXP we will prepare concise article on the subject,
put it on web site and submit to ARRL/QST publications (19th edition of ARRL
Antenna Book has it wrong)
Yuri, K3BU.us
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