Making calipers turn off.

After many years, it finally consumed all the batteries in the apartment, so it was time to fix it.


The label of screw threads was removed forever. It only looked neat, but was never used.



It's a dead simple capacitance measurer. There are no special alloys or manufacturing tolerances involved, just an arrangement of traces. The ruler has another arrangement of traces which form oppositely charged plates. There's no high precision manufacturing beyond normal PC board etching. It measures only relative change in position, so the longer the ruler is, the more it drifts off. The problem is calipers don't turn off.




There are many power switch workarounds involving a capacitor or an external battery. The internet never tried the obvious solution of connecting a power switch. It required severing 2 traces.



The switch always resets it to inches & requires zeroing, but the problem is solved. Whenever a new battery arrives, it should be a thing of beauty & a joy forever, again.