SubGigBoard
From Kevin Darrah Wiki
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The Blank Mini Board
Introduction
This is the Eagle Project that can be used to create your mini boards compatible with the Platform Board or as a stackable board with any of the other mini boards like the BLE Board or 328 Board
Download
The board and schematic files can be downloaded HERE
Tips
I use Eagle v7.6 (at least when these files were generated). Create a new project, then just drag these files right into that folder. Then I made this video recently showing how I hand assemble boards and where I get everything for the boards: