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Re: Topband: T Vertical feed

To: <topband@contesting.com>
Subject: Re: Topband: T Vertical feed
From: "Paul Christensen" <w9ac@arrl.net>
Date: Thu, 26 Jan 2012 14:31:09 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>
> The relatively high VSWR of this impedance can be VERY easily converted
> to 2:1 by simply adding a series capacitance equal to 110 ohms at 1825
> kHz. This brings the drive point Z to 25 ohms, which is 2:1, and much
> easier to tune in the shack.

Good point, Jim.  Or, go the extra distance and add L too and make it a 
complete low-pass L as was mentioned.  Then, the ATU on the shack table can 
breath a sigh of relief when needed with reasonable band excursions.

Even better for the industrious builder is to remotely motorize L and C. 
It's also possible to play around with T dimensions to minimize X at the 
feedpoint, but for me, that's too much tinkering up in the air :-)

Paul, W9AC 

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