Arduino Mega2560 nixie clock

- Low voltage

Some five years ago, I had a RepRap 3D printer setup running the Marlin firmware on an Arduino Mega 2560 board. With that long gone, I was thinking about some other projects I could try on it: a floppy drive controller, and perhaps a clock, with some neon indicators I have managed to salvage from a 1970s benchtop multimeter of Czechoslovak provenience. Even though I have to admit that it… [more]

CRT screen regenerator

- High voltage

With a predictable demise of CRT screens that’ve been phased out of production since the late 2000s, the owners of vintage TVs, monitors or other displaying equipment, kept in a condition that’s just too good to be thrown out, will eventually bump into a problem concerning each and every CRT – or any vacuum tube in general – of decreased cathode emission, … [more]

Nixie tube tester

- Low voltage

This very simple circuit can be used to verify the proper functionality of each cathodes in a Nixie tube, which was the predecessor of the solid-state LED 7-segment display, back in the 1960s and early 70s. The main anode voltage is obtained from a simple, battery-powered flyback inverter with just enough voltage to strike the glow discharge, and an adjustable resistor current limiter… [more]

Semiconductor free Geiger Counter

- Low voltage

Tried searching the keyword “geiger counter” on Google, or even better, on YouTube? Now, how many of them contained a multitude of transistors, analog microchips or even digital microprocessors, and no shielding at all? Well, whatever the count is, a majority of them – if not all – are going to fail miserably, due to a huge electromagnetic pulse, when the… [more]

Small Vacuum tube Tesla coil (VTTC)

- High voltage

To go along with flyback drivers, X-rays and other high voltage stuff, I have decided to build myself a Tesla coil. Because I live in an apartment building though, there would be no place to accommodate and run monstrous coil designs, not mentioning interference, so that is the reason why I’ve opted for small and sweet portable setups like this one is.… [more]