So, if there is someone in the group, who is willing to sell a nimo which might join the other five, pls. pm me.
jörg schrieb am Sonntag, 4. Oktober 2020 um 14:57:19 UTC+2: > Martin, you are right. > I've checked the getter flash and it is gone. Only a white shadow left. > So, sadly, the tube has sucked air and is cracked somewhere at the pins. > Unfortunately, I don't have a plasma ball. > > Dekatron42 schrieb am Sonntag, 4. Oktober 2020 um 01:20:23 UTC+2: > >> Have you got a Plasma ball to hold it to? If air has entered in you might >> see a very faint blueish glow if you turn off the surrounding light. >> >> What does the getter flash look like, like a mirror or is it gone >> completely, or has it gone white? >> >> I have seen a few Nixies where the Anode wire has come lose at a welding >> spot, can you see if something similar has happened to your Nimo with any >> of the wires or the Anode connection - if so you might smack it gently >> against your palm to see if the wire reconnects enough for it to work again? >> >> /Martin >> >> On Saturday, 3 October 2020 23:35:35 UTC+2, jörg wrote: >>> >>> Hi Gregebert, yes, I've checked the tube several times. The cold >>> resistance is about 2,1 ohm, which is identical to the other tubes. >>> Just swapped the tube with a running one on the same driver board. >>> Sadly, no function at all. Under a microscope, no crack is visible. >>> >>> I've made a short video to show the difference between a neon-nixie and >>> a nimo crt-tube and a neodym magnet (very small one.) >>> https://www.youtube.com/watch?v=JJytnrvTy3Q >>> >>> gregebert schrieb am Freitag, 2. Oktober 2020 um 19:25:40 UTC+2: >>> >>>> Jorg - Regarding the dead tube, have you compared the filament >>>> resistance of the bad tube to the others ? >>>> >>>> NIMO tubes have 2 parallel filaments, so if one is open, the resistance >>>> will be TWICE the value of a good tube. >>>> I think the cold resistance is around 3 ohms. >>>> >>>> If 1 filament is out, you can still get 5 numerals to work. >>>> >>>> I would be surprised if both filaments are burned-out, unless someone >>>> put way too much voltage on it, or the tube is cracked around the pins. >>>> >>>> If the filaments are OK, power-up the tube and make sure you get around >>>> 180mA of current. >>>> Then try varying the voltage between the filament and the logic driving >>>> the grids. If a grid is about 6 V more positive than the filament, you >>>> should get a numeral to turn on. >>>> >>>> On Thursday, October 1, 2020 at 1:44:20 PM UTC-7 jörg wrote: >>>> >>>>> Short update of my nimo project. >>>>> I've got 5 tubes running. The sixt is unfortunately DOA. >>>>> The tubes filaments are driven with three power supplies, with soft >>>>> start IC (load switch). >>>>> So the filament gets started very smooth. >>>>> I've made some experiments with multiplexing the tubes. >>>>> Which work nice, using the method described in the manual. The bias >>>>> voltage is changed for every tube, that should be on/off. >>>>> In the actual approch, I'm using direct driving the tubes via 74HC595 >>>>> shift registers. Got a plenty of problems at the beginning. >>>>> The power and signal lines for the 595 were messed with switching >>>>> noise. Some caps did the trick. >>>>> Really nice to view the working tubes. >>>>> >>>>> Video: https://www.youtube.com/watch?v=JbwfZhYhnlo >>>>> >>>>> jörg schrieb am Mittwoch, 15. Juli 2020 um 18:01:18 UTC+2: >>>>> >>>>>> I‘m using Eagle to layout. >>>>>> It takes time for me to feel comfortable with it. >>>>>> And Fusion360. >>>>>> >>>>>> -- 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/98be1adc-37d9-4213-bbfc-ff0a95a48ef2n%40googlegroups.com.
