Re: gEDA-user: basic anti-EMI design q

[DJ Delorie <dj@xxxxxxxxxxx>]

> Sorry if my question is dumb, but sometimes I see shields in printed
> circuits made by lines that crosses, forming a mesh. And sometimes I
> see shields made by a polygon.

AFAIK, a mesh screen is as good as a solid plane if the mesh spacing
is less than the wavelength you're interested in.  I don't know how
*much* less, but that's the general idea.

At least, when trying to use it as an antenna or RF shield.  I don't
know about internal fields or currents.

As far as manufacturability goes, it used to be that (1) there were no
polygons, so *everything* was made of lines like that, and fewer meant
smaller gerbers, and (2) it was mechanically (or
manufacturabilityally) advantageous to have some fraction of copper
and bare in each square inch of board.  Those days are long gone I
think.