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Re: QFH feeder ?



Hi Mak, SV1BSX

After carefully reading the original article of Walter Maxell, W2DU
"The Quadrifilar Helix Antenna" Chapter 22 from his book "REFLECTIONS
Transmission Lines and Antennas" ARRL Order Nr 2995 you can establish if
one article is correct and the other one is wrong because they both can be
correct depending on how the SMALL loop and the BIG loop are interconnected
to the "infinite balun" to get " 90 self-phasing of loops for end-fire
radiation or back-fire radiation as well self-matching to a 50 ohm
transmission line.

I have sent to you a copy of the above article.

Waiting for you on FO-29

Best 73" de

i8CVS Domenico

----- Original Message -----
From: "SV1BSX" <sv1bsx@yahoo.gr>
To: "Amsat-BULL" <amsat-bb@amsat.org>
Sent: Monday, November 14, 2005 5:27 PM
Subject: [amsat-bb] QFH feeder ?


> Hello AMSATs
>
>  I read 2 different articles about the half-turn / half-wavelength QFH.
> However I noticed that, the first article described that the "feeder"
> becomes from the down part of SMALL loop, while in the second article the
> feeder becomes from the down part of  BIG loop!
> (Both designs use the "infinite balun" technique.)
>
>  Both articles have equal Loops (L-Big=0.26 Lampda , L-Small=0.238
Lampda),
> but the
> Vertical Lenght is exactly the opposite between BIG & Small loops.
>
>  I wonder... is it the same ???
>
>  I made few months ago my 1st QFH-antenna (UHF) following the first
article
> and now I'm thinking if that is right or not !
>
>  Any comment is welcome.
>
> 73, Mak SV1BSX
>
>
> sv1bsx@yahoo.gr
> http://www.qsl.net/sv1bsx
>
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