We have developed a small PCB with a u-blox LEA-M8F GPSDO that fits on the USRP B200 and enables the use of the LEA-M8F as a time and frequency reference.
The board includes footprints for side-mounted SMA connectors and can also be used independently, powered by USB. The UART, USB and I2C interfaces to the LEA-M8F are available on the board.
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First version of the ODR LEA-M8F GPSDO board, with external 5V power. The USB micro connector is missing.
The board has been designed with the latest KiCAD build, and the design files are available on Github and are released under a CC-BY-SA licence.
This board is compatible with ODR-DabMod combined with the USRP B200, but it requires a customised version of UHD available here.
The board was produced at the Seeedstudio Fusion PCB service, with the following lea-m8f-productionfiles-may-2015. Schematics with soldering and setup instructions in PDF: lea-m8f-schematic-may-2015
The u-blox LEA-M8F can be bought on the u-blox webshop. All other components are available on Farnell, a BOM is available here.