On Fri, 2 Jun 2006 18:46:07 -0500
"James Cotton" <[EMAIL PROTECTED]> wrote:

> I think the problem with such an automatic approach would be that
> right now there isn't a good way to clear off unused copper islands
> from polygons, so that would reconnect them and make lots of little
> antennas all over your board.
> 

Leaving them floating as it is now would cause more problems IMHO. If you have 
an unconnected copper island next to a high frequency switching trace it would 
cause a capacitive coupling between the trace and the floating island. If that 
island has a natural resonance that lies near the switching frequency of the 
trace beneath it, then I have no idea what is going to happen. If that island 
is connected to ground I can treat it as a transmission line and calculate how 
big the gap between them needs to be to not being affected by the capacitive 
coupling.

Please correct me if I am wrong...

Regards,

Hans 

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