If your daily driver was born without a tach, fear not – a simple Arduino tachometer is well within your reach. The tach-less vehicle in question is [deepsyx]’s Opel Astra, which from the ...

This DIY optical spindle tach aims to fix that ... The display update speed is decent — not too laggy. Impressive build overall, and we like the idea of using a piece of PLA filament as a ...