Quantity   Component name
1 × HCPL-7720-000E Opto and Fiber Optic Semiconductors and ICs / Optocouplers and Optoisolators
2 × 47nF Capacitor
2 × Arduino Uno
2 × SD card 1 FAT partition for now, one file (.txt or .csv) for transfer
2 × Adafruit Assembled Data Logging shield for Arduino Product ID: 1141 (this is new version, it's different than old version, heads up)
2 × USB cables for Arduino power, or 9-12V power supplies