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- Add keepout layer around board
- Use a trace for 12 V instead of the long polygon
- Put the capacitors before the crystal for U1
- Replace SPI testpoints with a 5 pin header
- Move Q1 closer to U5
- Rotate C20 180 degrees
- Move trace from P7 to P3 to top layer
- Move LED3 to not cut the relay 12 V polygon