Re: S - Y Parameter conversion with Smith Chart

From: John Woodgate (jmw_at_jmwa.demon.contraspam.yuk)
Date: 07/31/04 

Date: Sat, 31 Jul 2004 22:22:17 +0100

I read in sci.electronics.design that Reg Edwards
<g4fgq.regp@ZZZbtinternet.com> wrote (in <cegvp8$gpk$1@hercules.btintern
et.com>) about 'S - Y Parameter conversion with Smith Chart', on Sat, 31
Jul 2004:

>It applied ONLY to the HF spectrum, serious calculating errors occurr if
>applied to the LF spectrum and below although few engineers realised
>this. And still don't.

Could you please explain that a bit more? The chart is a graphical way
of doing mathematics. Where does frequency enter the picture?

If you mean that the characteristic impedances of 'transmission lines'
at low frequencies aren't resistive, I quite agree. 

-- 
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

Relevant Pages

  • Re: S - Y Parameter conversion with Smith Chart
    ... Reg wrote that the Smith Chart doesn't work at low frequencies. ... 'fails' is that at low frequencies, ... The bad news is that everything is prohibited. ...
    (sci.electronics.design)
  • Re: S - Y Parameter conversion with Smith Chart
    ... >in the center of the Smith Chart lies on the purely resistive horizontal ... >transmission line. ... and at low frequencies jwL and G are negligible. ... The bad news is that everything is prohibited. ...
    (sci.electronics.design)
  • Re: S - Y Parameter conversion with Smith Chart
    ... >>The Smith Chart has served its purpose. ... >>applied to the LF spectrum and below although few engineers realised this. ... >What's the cutoff frequency below which a Smith Chart won't work? ... The bad news is that everything is prohibited. ...
    (sci.electronics.design)
  • Re: S - Y Parameter conversion with Smith Chart
    ... > What's the cutoff frequency below which a Smith Chart won't work? ... This question shows a limited understanding of the LF, and below, frequency ... spectrum. ...
    (sci.electronics.design)
  • Re: S - Y Parameter conversion with Smith Chart
    ... The Smith Chart has served its purpose. ... applied to the LF spectrum and below although few engineers realised this. ... low-loss HF transmission lines became the vogue. ... The pocket calculator could now, much more easily, with equal facility, ...
    (sci.electronics.design)
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