It's a current-stealing effect. If you search the old archives of the group you'll find that Pete Hand identified it and also proposed the use of a single transistor constant current sink driver as an alternative to the decimal point cathode resistor. I encountered the problem when developing my Niximatrix clock that uses IN-12B, and experimented with the current sink driver per his recommendation - it works a treat.
Jon. On Friday, September 12, 2025 at 3:21:23 PM UTC+1 Jarod Findley wrote: > Its looks like your voltage or amperage is high try cutting it back a few > volts or a miliamp > > On Fri, Sep 12, 2025, 7:45 AM newxito <[email protected]> wrote: > >> I have the problem with all my IN-12B... >> >> Schematic of the display: >> https://github.com/axtar/Nixie-Calculator/blob/main/Schematics/Schematic_Nixie_Calculator_IN-12_Display_Rev2.pdf >> If using the B version I populate the 82K resistors. If using the A >> version, I populate the neons and the 270K resistors. >> >> Schematic of the driver: >> https://github.com/axtar/Nixie-Calculator/blob/main/Schematics/Schematic_Nixie_Calculator_IN-12_Driver_Rev2.pdf >> Just the usual HV5622 thing... >> >> What resistor values are you using for your Bitcoin Ticker? >> >> Michail Wilson schrieb am Freitag, 12. September 2025 um 13:13:08 UTC+2: >> >>> Something is wrong. >>> >>> >>> >>> My project (Bitcoin Ticker) uses 8x IN-12B and they (hundreds of tubes >>> worth) don’t have that issue). I used the 12B since it has a decimal point >>> on both sides. >>> >>> Have you tried another tube? What’s your project schematic? >>> >>> >>> >>> M1 >>> >>> >>> >>> *From:* [email protected] <[email protected]> *On >>> Behalf Of *newxito >>> *Sent:* Friday, September 12, 2025 1:09 AM >>> *To:* neonixie-l <[email protected]> >>> *Subject:* [neonixie-l] IN-12B decimal point >>> >>> >>> >>> I was told several times to use IN-12B instead of IN-12A with neon bulb >>> as decimal point. I finally tried that but I don't like it. Is anyone using >>> the decimal point of an IN-12B in a project? When combined with a 3 or 8, >>> the point is barely noticeable. Another problem I'm having is that it glows >>> much brighter when no digit is lit. As soon as a digit is lit, it gets >>> dimmer. Is this normal or I’m doing something wrong? I use a 15K anode >>> resistor and an 82K cathode resistor for the decimal point with a voltage >>> of 170V. >>> >>> >>> -- >>> 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, visit >>> https://groups.google.com/d/msgid/neonixie-l/613d7d66-dcab-48ae-bd34-a5f714071e72n%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/neonixie-l/613d7d66-dcab-48ae-bd34-a5f714071e72n%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> 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, visit >> https://groups.google.com/d/msgid/neonixie-l/c9cbf447-021e-4b3f-bf5a-b1871d3c94e6n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/neonixie-l/c9cbf447-021e-4b3f-bf5a-b1871d3c94e6n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- 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, visit https://groups.google.com/d/msgid/neonixie-l/95b2f5b7-6a04-496c-a9ca-f14670eede6en%40googlegroups.com.
