On Mon, 31 Aug 2009 21:43:02 -0500, tom wrote:

Funny, every yagi I've designed and built has a driven element which is
NOT resonant. It has a non-resonant element and a matching network of
one sort or other, which is entirely different than being resonant. And
strangely enough, is high 90's efficient. Which Art claims isn't possible.

tom
K0TAR

Huh? I can tune across the frequency range of a Yagi-Uda antenna,
measure the VSWR, and most certainly see a resonance dip at the design
center frequency. I can also attach a grid dip meter to the feed,
through a coupling loop, and see the resonance. Take away the
reflector and directors, and we're left with an ordinary dipole, which
is most certainly a resonant antenna. If the driven element is not
resonant, what is producing the dip in VSWR at the design frequency?

Goggling for added support:

http://www.hamuniverse.com/yagibasics.html
"The Yagi antenna's overall basic design consists of a "resonant" fed
dipole..."

"Resonance phenomena on Yagi arrays"
http://adsabs.harvard.edu//abs/1981CEEJ....6....9T

http://books.google.com/books?id=ujr0WOkx_nkC&pg=PA123&lpg=PA123&dq=yagi+r esonant&source=bl&ots=VLXGYNabey&sig=6r-TqPQHdMNb9Zg9sV8olViIeTc&hl=en&ei=7LWcSszEG4ayswPc wK2TDg&sa=X&oi=book_result&ct=result&resnum=12#v=o nepage&q=yagi%20resonant&f=false
"Resonant with directivity...yagi..."



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Jeff Liebermann
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