peteg's blog - hacking - nixie clock - 2010 01 08 Nixie PS

Further adventures in nixie land

/hacking/nixie_clock | Link

Well! After a few hours of burning some digits in, the sacrificial tube is looking pretty good. The '5' does not light the lower-left arc, and I'm not sure what I can do about that.

As for the power supply, I revise my earlier comment to say that now I would simply buy a pre-built unit from John Taylor. They're small, and for $US10, cheaper than acquiring the requisite bits.

My perf-board effort is getting tidier and more finished, albeit at the cost of much solder and desolder braid. It seems stable, with tight regulation at 182v from no load up to about 3mA after replacing my 1.5Ω current sense resistor with 0.33Ω. Apparently I should run the tubes at something like 1.5 times the rated current, allowing for multiplexing, so the supply really needs to go to 8mA. I'll leave that to another day.

I found that the multimeter leads (hooked across the anode resistor) radiated enough to interfere with the radio. However even when removed, the TV still got a pincushion effect. (I'm glad I still have an analog TV.) Placing the whole thing on top of my venerable regulated power supply eliminated any visible or audible effects, which is reassuring but not yet sufficient for confidence. I'm wondering how I can improve the grounding and shielding without huge amounts of solder or metalwork.