Open-source boards designed in KiCad by osprey-dcs on GitHub, from 4 repositories. A board’s address here is its repository’s there.
osprey-dcs/clk-input-fmc
Clock Input FMC board design
osprey-dcs/pmod-mps-io
Quartz PMOD MPS I/O board
osprey-dcs/Quartz
Quartz ADC PCB OSH repository
osprey-dcs/ttl-io
pmod: 4 TTL in and 4 LVTTL out w/50 ohm drive