Quantity   Component name
1 × Wemos mini module WiFi access point + web server, ￡3.12 on aliexpress
1 × ADS1115 (or ADS1015) ADC module Measures voltages, around ￡1.50 on aliexpress
1 × Wemos tripler base Connects three modules together, ￡1.12 on aliexpress
4 × Through hole resistor of around 10 kOhm Protection for the ADC inputs
1 × Turned pins strip (min 5 pins) To insert jumper wires
1 × Wemos battery shield, £1.96 Charge a LiPo battery from a USB charger
1 × LiPo battery with overdischarge protection To enable autonomous operation without grounding the instrument
1 × Potentiometer (optional) To have a variable voltage source on board