X-rays with a DY86

The DY86 (DY87, DY802) vacuum rectifier was used in most European black and white tube television sets. In hot-cathode mode, it was capable of rectifying up to 18 kilovolts at 0.5 mA. In cold-cathode mode, however, it withstands 40 kilovolts DC inverse for a short time, while providing some soft X-ray radiation enough to set classic Geiger counters off.… [more]

Semiconductor free Geiger Counter

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]