[TowerTalk] S21 to Rp & Cp - Equivalent Circuit

[Steve Hunt]

A couple of additional "power" signs appeared when I cut & pasted that 
formula from my web site into my email client. It should be:
R = (100.cos(θ).10 ^(- |S21| / 20) ) - 100

Thanks to Maximo for pointing it out.

It's exactly the same formula as Rick's for his special case of a 
resistive DUT, but with the addition of a cos(θ) term.

Steve G3TXQ


On 14/01/2018 13:19, Steve Hunt wrote:
> The general case is simpler than I originally had it, because I'd 
> missed a simplification using a trig identity. The revised version is 
> here:
> http://www.karinya.net/g3txq/chokes/s21.pdf
>
> R = (100.cos(θ).10 ^(- ^|S21| / ^20) ) - 100
>
> X = (R+100).tan (θ)
>
> Steve G3TXQ
>
>
>