Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

I have just completed my first board using PCB Artist and photo etching myself. Two ICs (PIC chip and interface) pluse a few resistors, caps, regulators and connectors, all standard through board types. I needed double sided to get all the tracks connected so most tracks are on the bottom with a few pins as vias as I can't do PTH. The board works well but noise is a problem mainly affecting the 10 bit A/D inputs due to proximity to a couple of PWM drives. The only way I can see to improve noise is a copper ground fill on the top layer. I tried this but the spacing between copper fill and non-grounded pads and tracks is too close for my liking. Can someone tell me how I change the spacing?
Thanks
Richard (Dick) G4BBH