Max. Range: 9,950 meters with two digits slip it in pants’ pocket For walking and jogging This circuit measures the distance covered during a walk. Hardware is located in a small box slipped in pants’ ...

I got some Geiger tubes a few days ago and built a very simple Geiger counter circuit that is powered entirely through the microphone jack (microphone connection provides a little power for things ...

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 ...

In frequency counters, the gating time allotted for counting is often too short to resolve low frequencies. A phase-locked loop could be used to multiply the input frequency. But in some cases, the ...

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 ...