Suppose you want to measure a slowly-varying voltage from a sensor, or perhaps plot the discharge curve of a battery. Is it really necessary to sit there and note down a reading from the multimeter every so many seconds or minutes? It is less tedious and much more elegant to use this Arduino-based unit connected to your oscilloscope.
Two questions motivated the author at the beginning of his project: ‘is my battery any good?’ and ‘is this charger charging my battery correctly?’.
 

The Voltage Tracker Project on Elektor LABS or in Elektor Magazine (for Elektor Members only).

Bonus track: Christmas Starlet DIY Kit [Limited Edition!]