Have tried now with the series resistor (used a pot). but it does not affect brightness. Also current stays between 280-300uA, regardless which value the series resistor has. Did expect current to either rise or fall when changing the resistor value (ohm's law), but it just stays the same. funny.
I have a feeling my "problem" is related to the hv supply, which is probably better suited to charging a capacitor than supply a load. Have yet to try with reduced driving speed... On Sunday, October 6, 2024 at 9:08:01 AM UTC+2 Martin Kaufmann wrote: > Thank you very much for your explanations. > > The OG-4 type draws 400-450 uA according to specs. I'll try to see, if > there is potential with optimizing the series resistor. > > As for the drive speed. Currently I use 200us - if my math is right, I am > more in the range of 5000Hz with this (probably divided by two, due to the > nature of my isr stepper routine). Maybe I have to reduce speed as much as > possible without getting into "flickering" in order to max. out brightness. > Gonna try this too. > > Alternative tubes or leds are not an option - it just matches perfectly > with the in-4 nixies I will combine the dekatron with. I really love the > optics here :-) > I've seen this sort of dekatron-animation with clear bright glows on all > of the cathodes - this tells me it should be feasible... > > On Sunday, October 6, 2024 at 6:17:19 AM UTC+2 gregebert wrote: > >> Brightness is a function of current; more current=more brightness, but >> also causes more wear out of the tube. It's important to stay within >> datasheet recommendations, otherwise your tube will fail prematurely. >> Brightness is increased by increasing the high-voltage supply or reducing >> the series resistor value, or a combination of the two. I have a single >> A-101 dekatron in one of my clocks, and it's been running 27/7 for 11 years >> now with no visible degradation. I think my supply voltage is around >> +500VDC, and the series resistor is around 470K [sorry, that's from memory >> from 2013...] >> >> Brightness is also a function of how much (or little) the pattern >> changes. If you are trying to get a full-circle on a dekatron, it will need >> to be spinning about 30 times/second to trick your eyes. There are 30 dots >> per revolution on a dekatron, so that's around 900Hz. Since the individual >> dots are only glowing 1/30 of the time for a full-circle pattern, they are >> going to be noticeably dimmer than a stationary dot; you can see this in >> your photos. >> >> If brightness is paramount, then you would be better off using 30 LEDs >> (or 30 neon bulbs....) in a ring and drive them individually so they can be >> on 100% of the time for max brightness. It's not as cool as a dekatron, but >> it is brighter. >> >> On Saturday, October 5, 2024 at 2:21:25 PM UTC-7 Martin Kaufmann wrote: >> >>> https://threeneurons.wordpress.com/ - yes, this was/is my main info >>> site regarding these tubes. being a noob, I did not fully understand >>> everything though. Also cannot recall to have read something about >>> controlling tube brightness, but I might have missed it and will check >>> again. >>> >>> On Saturday, October 5, 2024 at 11:08:38 PM UTC+2 Mac Doktor wrote: >>> >>>> >>>> On Oct 5, 2024, at 4:50 PM, Martin Kaufmann <[email protected]> wrote: >>>> >>>> maybe one of you who truly understands dekatrons, can explain to me or >>>> give me a hint, >>>> >>>> >>>> Just to be clear, have you seen/devoured this site? >>>> >>>> https://threeneurons.wordpress.com/ >>>> >>>> >>>> I take it that Mike is one of leading lights in the Dekatron realm. >>>> >>>> >>>> Terry Bowman, KA4HJH >>>> "The Mac Doctor" >>>> >>>> https://www.astarcloseup.com >>>> >>>> "If only you could see what I've seen with your eyes."—Roy Batty, *Blade >>>> Runner* >>>> >>>> -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/43a0a93a-22c3-4884-96fb-a2d71f02f739n%40googlegroups.com.
