Hi Tomasz, to me it looks like there is some kind of either capacitive coupling or leakage between the different drivers. You can see this from the different levels of the voltages at anode. Besides what has been suggested to you, I would strongly advise to add a bleeder resistor between the base of the A42 (Q18) and ground. If the control voltage is 5V, then 2.2K would do. Another option (just to help troubleshooting but involves no soldering) is to change the driving sequence to avoid adjacent tubes to be driven one after the other. For example if you are driving the tubes in 1-2-3-4 sequence, you can try with 1-3-2-4, which should produce ghosting only between tubes 2 and 3.
Hope this helps. Gaston On Wednesday, January 17, 2018 at 3:58:39 PM UTC-3, Tomasz Kowalczyk wrote:Hi, I've been testing the popular anode switching circuit with one NPN and one PNP transistor. The circuit with my values is shown below: > > > <https://lh3.googleusercontent.com/-KY9FZBzfztc/Wl-WzE8pZHI/AAAAAAAAC30/1jnJ6o2PVCQ0RVU6gYXqy1PjjmqiJTHPgCLcBGAs/s1600/anodeswitch.png> > > > > > > > > > > > > > > > > > > > > > > > > -- 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 neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/dad3ffd7-9c44-4916-aa6c-86f8d9b13b9d%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
