Version based on Notecarrier A and with built-in IMU.
The first version of the SFY. Also with a PCB which can be imported into EasyEDA.
Instructions for building with PCB: SFY Tutorial v0.3 Instructions for building and assembling without PCB: Ocean Buoy to Measure Waves and Drift using Low-Power Cellular. Bill-of-material is available as a spreadsheet.