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Re: Topband: Efficiently Matching Low-Impedance Antennas to 50ohms

To: "Herb Schoenbohm" <herbs@vitelcom.net>,"Ron Majewski" <bigsky2000@sbcglobal.net>, <topband@contesting.com>
Subject: Re: Topband: Efficiently Matching Low-Impedance Antennas to 50ohms
From: "Ulrich Weiss" <dj2ya@t-online.de>
Date: Fri, 23 Sep 2005 09:12:11 +0200
List-post: <mailto:topband@contesting.com>
hello Ron,

From: "Herb Schoenbohm" <herbs@vitelcom.net>
> You can get close to what you want  (about 25 ohms) by tying two pieces of
> 50 ohm coax equal half wave lengths (in coax factoring the velocity
factor)
> in parallel  hooked shield to shield and center conductor to center
> conductor...in series with the 50 ohm coax feed and the antenna.  This
> should bring you in the ballpark and totally avoid any tuner losses.

Herb's suggestion will reduce your SWR to 1.6... using 75 ohm line would
yield 1.4 and if you can get hold of 60 ohm line you'd be pretty close to a
perfect match...
after reading Maxwell's, Another Look at Reflections, I ask myself (and the
reflector) if it's really worthwile to improve the match at the feedpoint of
the vertical...
regards

Uli, DJ2YA

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* Ulrich Weiss, Am Birkenstrauch 15, D-57334 Bad Laasphe, Tel.:
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