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From: Jeroen Belleman <jeroen@nospam.please>
Newsgroups: sci.electronics.design
Subject: Re: Quarter-wave whip earth plane
Date: Sat, 15 Mar 2025 12:14:40 +0100
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On 3/15/25 10:23, Liz Tuddenham wrote:
[Snip!]

>  I need to do a crash
> course in interpreting Smith Charts.
> 
> 

I suppose it's enough to know that you want the curve to be
as close as possible to the centre of the chart at the working
frequency. That's where the load impedance matches the
characteristic impedance.

A Smith chart is a chart of the voltage across a Wheatstone
bridge with a funny grid mapping that back to the value of one
of the bridge impedances. It was handy as a graphical aid to
calculate impedance transforming networks and more, but
nowadays computers can do that much better and much faster.

Jeroen Belleman