The ATmega328-based millivolt meter based on a design by Scullcom Hobby Electronics has been serving well on my bench. But time for a couple of mods:
- adding a 9V internal battery that can be used when not connected to external supply - great for when the bench is crowded
- simple reverse-polarity protection (inline rectifier), particularly to avoid any confusion over centre-negative/centre-positive power connectors
As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub
