David:
The ARRL publish an Antenna Book which includes a diskette with
software. One of these DOS programs is Transmission Line Analyzer. You can
do the calculations you inquire about with this program, sort of. If you
know the feedpoint impedance of your halfwave antenna, you can calculate the
L and C values of a matching network with this program.
You can download the EZNEC demo software from Roy W7EL's web page
(http://eznec.com ) and use it to find the approximate feedpoint impedance.
Then you can use ARRL's TLA SW for the values.
GL es 73 de
Gene Smar AD3F
-----Original Message-----
From: David Douglass <vk2dpd@bigpond.com>
To: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Wednesday, August 29, 2001 11:05 AM
Subject: [TowerTalk] halfwave verticals
>
>
>
>
>Hi all,
>
>I'm in the process of building some halfwave verticals to use portable on
HF
>with the aid of a DK9SQ telescoping fibreglass pole.
>
>I am building the LC matching system to convert the high impedance at the
>end of the halfwave down to the 50ohms to match the coax.
>
>My question is this! I'm sure in the past I have seen a computer program
>that allows you to key in the frequency and it will give you the length
>required and the values of inductance and capacitance required.
>
>Does anyone know were I can locate this program or if there is a manual
>calculation I can use for the LC values.
>
>Regards
>
>David, VK2DPD
>vk2dpd@qsl.net
>vk2dpd@bigpond.com
>
>
>
>
>List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
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>
>-----
>FAQ on WWW: http://www.contesting.com/FAQ/towertalk
>Submissions: towertalk@contesting.com
>Administrative requests: towertalk-REQUEST@contesting.com
>Problems: owner-towertalk@contesting.com
>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 96 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
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