That is a nice module you got there! I don't want to spend too much time on this and definitely not act as if I know everything better, but your circuit is powered by 170V which means the mentioned problem wouldn't be there.
I draw a small circuit here: http://xiac.com/Images/Nixie300V.GIF The only thing I tried to say is that if the transistor is conducting, the current through the nixie segment is about 3.8mA (300 - 150)/39k. When the transistor is turned off, the current will still be (300-150-100)/39k = 1.3mA, which means IMO that the segment does not turn off (it is less bright, but not off). On the other hand, if a real MPSA42 transistor was used, the zener clamping diode wouldn't be there and for that reason the segment does turn off. Or am I missing something? Michel -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
