In this project we are building a basic and low cost frequency counter circuit . It can measure from 16Hz to 100Hz signals with a maximum amplitude of 15V. The sensitivity is high, the resolution is 0 ...

This is an oldie, but oh, man is this ever good. It’s a Nixie clock made without a microcontroller. In fact, there aren’t any logic chips in this circuit, either. As far as we can tell, the logic in ...