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Re: gEDA-user: Compiling MMI (electromagnetic simulator)



On Mon, Aug 23, 2004 at 09:33:31PM -0400, Dan McMahill wrote:
> On Sun, Aug 22, 2004 at 06:13:34PM +0000, Karel Kulhav? wrote:
> > Hello
> > 
> > MMI promises to compute distributed paramteres of copper strips on
> > PCB.
> 
> looks neat once it can be built.  I've started and found some issues
> with the build system.  Haven't fixed them all yet...
> 
> 
> > I am lured by an idea of computing how many picoforad 1cm^2 of PCB trace on my
> > 1.5mm FR-4 board makes. 
> 
> try out mcalc.sf.net to find impedance (sqrt(L/C)) and velocity (1/sqrt(LC)) of
> your line and then solve for L and C.

Yes it works thanks.

> 
> Thats useful for lines which are relatively long compared to their width.
> for a simple parallel plate thing like what you have, you can 
> 
> a)  note that 1cm is a good bit more than 1.5 mm so just use C = eA/d
>   (e = permitivitty of FR4 which is around 4.8x free space permitivitty)
>   (A = area)
>   (d = distance)
> 
> or 
> 
> b)  use something like fastcap if you want a more accurate field solution.

This Project Has Not Released Any Files 
http://sourceforge.net/projects/fastlc/

Don't you know where to download it's files?
I didn't find it on freshmeat and opencollector.

Cl<