[Antennaware] Summary of replies: Designing L-Networks for antenna matching

[David Gould]

I have had a good number of replies, for which I am very grateful.
Thanks to all those who sent advice.
I will briefly summarize what I have discovered.

Nec2go   www.nec2go.com  is a commercial antenna modelling package which 
has a network design component.  The demo version does not allow you to 
enter your own values of R and jX. it can only use the values that come out 
of the antenna modelling.    I believe the full version does allow the 
entry of your own values, it gives all four solutions where appropriate.

There is also   http://www.qsl.net/mmhamsoft/mmana/    This is also an 
antenna modelling package but is freeware.
The network design tool is hidden, you have to go to 'Options' and then 
'Options and Setup'   I could only get it to produce two possible solutions 
when in practice there are sometimes four.

There is also this link which is obviously not very well known as it has 
only been accessed about 70 times since 1997.  But does exactly what I 
wanted, plus a lot more with T , PI and various other combinations.
http://bwrc.eecs.berkeley.edu/Research/RF/projects/60GHz/matching/ImpMatch.html

Finally I have been told that there is a program on the CD with the latest 
ARRL antenna handbook which does the calculations.  I have not been able to 
check this out.

I hope this might be useful to other people.

73,
Dave G3UEG



>Date: Sat, 06 Mar 2004 13:09:03 +0000
>To: antennaware at contesting.com
>From: David Gould <david.gould at btinternet.com>
>Subject: Designing L-Networks for antenna matching
>
>I am modelling vertical antennas for the low bands using EZNEC (windows)
>I then use a very old DOS program for designing L-Networks for 
>matching,  that does take complex impedances into account.
>
>I would like to find the set of equations for L-network design for 
>matching complex impedances one side to resistive the other.  Does anyone 
>know a source?  I could then build them into a spreadsheet.   (I have 
>searched the web and can only find formulae for resistive input and output)
>
>Secondly,  Does anyone know of a WINDOWS program that does the calculations?