PC boards

[Terry Bowman]

>Are there any programs that you enter a circuit and it outputs a pc board
>layout for you?
>Also, how does every body come upwith their pc board ideas?
>John S.

One good way to start is to breadboard your ciruit (it doesn't have to be
complete and functional, although that helps) and use the breadboard layout
as your starting point. This eliminates a lot of guesswork.

I design my PC boards with, of all things, Adobe Illustrator, which is
supposed to be a PostScript drawing program for graphic artists but works
fine for PC boards (version 7 has layers, too). I set the cursor movement
distance to .05", drew a bunch of pads for typical IC's, transistors,
resistors, capacitors, etc., and started drawing. A dial caliper accurate
to .01" comes in handy for measuring parts but I got by for a long time
with an old drafting scale instead. My PC boards are small and tight
because I measure everything exactly and Illustrator positions everything
precisely; saves on expensive pre-sensitisied board (you really don't need
a 4" x 6" board or a eurocard just for an LFO, man).

Any decent drawing program will work, you just need to create a library of
pads for it. Note that I haven't tried double-sided boards yet--maybe now
that Illustrator has layers...

Terry Bowman, KA4HJH