| Item | Amount | Article number | Comment |
|---|---|---|---|
| Raspberry Pi | 1 | we used a 3 B+ | |
| MicroSD card 16GB | 1 | ||
| CitizenSensor Raspi HAT | 1 | see folder 1_RaspberryPi-HAT | |
| CitizenSensor electrometer board | 1 | see folder 3_Electrometer | |
| CitizenSensor connector board | 1 | see folder 4_ConnectorBoard | |
| Load cell 100g | 1 | Sparkfun TAL221 | |
| HX711 breakout board | 1 | ||
| KY-040 rotary encoder | 1 | ||
| USB 90° adapter | 1 | Reichelt DELOCK 65668 | |
| USB socket with cable | 1 | Reichelt DELOCK 85245 | |
| Display | 1 | Reichelt RASP PI 3.5TD | |
| Ribbon cable 26-way | 1 | Reichelt AWG 28-26G 3M | |
| Socket 2x20 | 1 | Reichelt PFL 40 | |
| Connector 2x13 | 1 | Reichelt WSL 26SK | |
| BNC jack | 1 | Pollin 94-450423 | |
| Raspi power supply | 1 | Reichelt RASP NT 25 SW E | |
| Enclosure | 1 | 3d printed | All parts from folder 5_Enclosure |
| Screw M2.5x5 | 4 | for mounting Raspi | |
| Screw M3x10 | 6 | enclosure and load cell | |
| Screw M3x20 | 2 | load cell | |
| Brass insert nuts M3 | 8 | ||
| Brass insert nuts M2.5 | 2 | ||
| Nitrate electrode | 1 | Conatex Pasco 1184013 | https://www.pasco.com/products/sensors/environmental/ps-3521 |
| Magnet for stirrer | 2 | Reichelt MAGNET 3.4 | Diameter 3mm, Length 4mm |
| Motor for stirrer | 1 | Reichelt SOLAR 90002L |
| Item | Amount | Article number | Comment |
|---|---|---|---|
| Power supply, USB micro | 1 | 5v, 2.5A | |
| Magnetic stir bar | 1 | behr-labor.de 6231865 | oval, 15x6mm |
| Plastic cup with screw cap | 5 | https://www.ebay.de/itm/112857368035 | 100ml, Diameter 43mm |
| Screw cap with hole for electrode | 1 | see folder 6_Accessories | 3d printed |
| 100g calibration weight | 1 | e.g. https://www.ebay.de/itm/140864008419 |