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On Wed, 17 Dec 2003 06:44:06 GMT, Roger Halstead
wrote: |On Fri, 12 Dec 2003 22:32:07 -0700, Wes Stewart |wrote: | |On Sat, 13 Dec 2003 00:06:16 GMT, Roger Halstead wrote: | || ||Every HF antenna here will go 1:1 "some where" ... | |Not so. | |I'd like to know how you can say that? I can say it because it's true. | |Have you measured all my antennas? No, but I've measured some of mine. Why just yesterday, I was out measuring my vertical that started out as a Cushcraft AV-80. I'm looking to use it on 40 meters. At resonance, at about 5.43 MHz, the base impedance was 38.5 +j0. That's a 1.3:1 SWR. And BTW that's a datum taken using a method described in HP Application Note 77-3, "Measurement of Complex Impedance 1-1000 MHz." You mistakenly believe that because an antenna *has a resonance* at some frequency, its SWR is *1:1*. Not so, as shown above. I have shown at least *one* example where you are wrong when you say *every antenna*. | You are welcome to come over and |check them out. No thanks. The weather here is much nicer for doing antenna work. | Every one "according to my meter which is a Bird" |reaches 1:1 some where in the desired band. It may not be exactly the |frequency the formula predicted, but it'll be relatively close. | |Roger Halstead (K8RI & ARRL life member) |(N833R, S# CD-2 Worlds oldest Debonair?) |www.rogerhalstead.com |Return address modified due to dumb virus checkers | |