[neonixie-l] Re: Numitron clock driving question

Series resistor on filaments will also reduce the surge-current when the segment is turned-on, greatly extending the lifetime. >From what I've researched on tube filaments, reducing the surge-current during turn-on (ie, adding series resistance) is the best way to extend lifetime. There

[neonixie-l] Re: Numitron clock driving question

Hi Mark, It's nice to find another burner on the list. Larry On Friday, February 23, 2018 at 8:10:24 AM UTC-6, Mark Moulding wrote: > > > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails

[neonixie-l] Re: Numitron clock driving question

On Wednesday, February 21, 2018 at 1:39:24 PM UTC, Terry Kennedy wrote: > I have a pair of Numimini clocks (from Jon Ellis here) with IV-9 tubes >> which have been running continously here for over 8 years with no issues. >> They are powered by the host PCs' USB ports, so there is some magic

[neonixie-l] Re: Numitron clock driving question

Thanks! That's alot of positive information - it seems that numitrons are indeed sturdy devices and they do not need that much protection as I thought. What is the frequency of the dimming PWM? I wonder how high it has to achieve steady temperature due to thermal inertia of filaments. PWM

Re: [neonixie-l] Re: Numitron clock driving question

Just one correction: inrush current of a filament lamp (or heater) is a physical characteristic of the component and not something one designs to happen. Every filament or heater be it huge or tiny has an inrush current, and the amount of it and the time that takes between this maximum current

[neonixie-l] Re: Numitron clock driving question

I've built quite a few Numitron-based clocks, as well as other displays using the technology. Personally, I love them: they're easy to drive, last a *long* time, and are, to my eyes anyway, very attractive. They provide a wonderful glow, and because they're broad-spectrum, they can be

Re: [neonixie-l] Re: Numitron clock driving question

Instead of the CD4511, have you considered multiplexing ? It should work very well for incandescent displays because of their inherent storage time and you wont have any visible flicker. And best of all, no ghosting !! You can also add PWM to keep the dark segments warm, which should help

Re: [neonixie-l] Re: Numitron clock driving question

I didn't purchase any numitrons yet, however my tests with a CCS and a small 15V 30mA bulb show that with current limit of 20mA, the filament turns on with a fade in effect, which takes about 200ms, in this case. I enjoy it, so I hope I'll be able to reproduce it with numitrons, as it would

Re: [neonixie-l] Re: Numitron clock driving question

Bottom line: Keep the current as low as possible, and limit the inrush current. I've done a fair amount of research on extending filament life for a project I'm working on. After a lot of tradeoffs and analysis, the best solution for me was to use a *higher* operating voltage and add series

Re: [neonixie-l] Re: Numitron clock driving question

On Wednesday, February 21, 2018 at 7:43:27 AM UTC-8, nixiebunny wrote: > > The inrush current performs the important job of heating up the filament > so that it will glow. Don't expect an LED driver to work well. Experiment > with some low ohmage series resistors first.t >

Re: [neonixie-l] Re: Numitron clock driving question

The inrush current performs the important job of heating up the filament so that it will glow. Don't expect an LED driver to work well. Experiment with some low ohmage series resistors first. On Feb 21, 2018 6:39 AM, "Terry Kennedy" wrote: > On Wednesday, February 21,

[neonixie-l] Re: Numitron clock driving question

On Wednesday, February 21, 2018 at 8:26:39 AM UTC-5, Tomasz Kowalczyk wrote: > What are your experiences with numitrons? What methods of prolonging their > life did you use? Or did you just ignore the problem, as IV-9 and IV-16s > are still quite cheap? > Please share your experiences and