Learning Eagle

With the basic parts and function list in my head, it's time to start arranging this stuff on a circuit board.  The ubiquitous choice for hobbyists seems to be Eagle.   Since they offer a free version, and it runs happily on Linux, it will be my choice as well.

One of the limitation in the free version of Eagle is PCB size.  After only a little experimentation I've determined that I will not be able to fit everything within their constraints.   The only (free) solution I can think of is moving functional groups of components to separate boards, and I will bus them together with some ribbon cable or something.

Here's an initial terrible layout for the audio board.   I have no doubt that I'm making lots of mistakes, but it's strangely compelling and fun.

That's the five DS1807 digital Pots in the center.   The two headers would go to the mainboard and an I/O board (full of 1/4" jacks).   In the upper left is the MSGEQ7 chip.