R|Z568M

Handmade in the Czech Republic by Dalibor Farny, modeled after the classic Z568M. The R|Z568M is a large end-view nixie tube with a 50 mm digit height, built for longevity and premium clock and display builds. Additional specifications Weight: 110 g Extinguishing voltage (typical): 120 V Storage temperature: -20 C to +60 C Operating temperature: -10 C to +50 C Expected lifetime: over 20 years / 200,000 hours (running 24/7) Driving circuit Connect the anode to a 170 VDC supply through an anode resistor; a step-up converter producing 170 VDC from a 5-12 VDC input is recommended. To light a digit, pull its cathode pin to ground (0 V) via direct wiring, discrete high-voltage transistors (e.g. MPSA42), or a driver chip (e.g. Microchip HV5622). High voltage can be lethal - never touch the high-voltage contacts. Simple drive: one MPSA42 transistor per digit (10 total); base at 5 V lights the digit, 0 V turns it off. Size the anode resistor for a peak dissipation of about 300 mW (use a 2512 package). Downside: slight brightness differences between digits cause uneven sputtering and faster poisoning of rarely used digits. Recommended drive: MPSA42 per digit plus per-cathode resistors that equalize digit currents and reduce poisoning. Anode resistor 4.7 kOhm; resistor dissipation about 200 mW (1206 package). Suggested cathode resistors: 0 = 1.2 kOhm, 1 = 4.7 kOhm, 2 = 1.1 kOhm, 3 = 1.5 kOhm, 4 = 3.3 kOhm, 5 = 1.1 kOhm, 6 = 1.1 kOhm, 7 = 3.6 kOhm, 8 = 0 Ohm, 9 = 1 kOhm. Cathode poisoning prevention routine Digits that are rarely displayed develop cathode poisoning over time. To prevent it, periodically exercise every digit: for each 60 s a tube stays lit, briefly light every other digit for about 0.2 s (a 60 s : 0.2 s ratio). Scale proportionally for longer static periods - a digit held for 600 s should see each other digit lit for about 2 s over that span. Source: docs.daliborfarny.com