Generally speaking, the more ground plane -- top and bottom -- the better. The last step in most of my designs is to do a polygon fill tied to GND on both sides of the board.
--- In Homebrew_PCBs@yahoogroups.com, "Andrew" <a_wake@...> wrote:
>
> I am closing in on designing a board that is a mix of SMD and through hole parts. I am using a zone on the bottom side to provide a ground plane; I wondered about adding a zone to the top as well. If I did a top zone, is there any reason I can't make it a ground plane as well?
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