Nice clock! Thanks for sharing! I am building a similar clock myself right now and I have read a lot of what the Russian people write about these tubes and there are some small design ideas/changes that they have come up with that differs from your design - I have incorporated these in my design as the Russians say that they are essential to long life of the ITS1A/B's. I don't know if the Russians are right on this or not but they all seem to use the same design.
What they have done is adding a resistor in series with each of the second anodes (Anode-2 @ pin 14) as a current limiter. I have seen values ranging from 2.2 k up to 47 k in different designs, but with my ITS1B's a value below 10 k works best when the MPSA92 is supplied with +90V. They also put a 56k resistor between the first and the second anode (Anode-1 @ pin 2 and Anode-2 @ pin 14) as that stabilizes the zener voltage and the circuit. I am in no way an expert on these tubes as I have only been fiddling around with them for a few weeks since I bought mine, but I think that the designs that the Russians are using are from various books and datasheets that they have access too, at least that is what I have gleaned from what they have written. My design will also include a driving stage (MPSA42/92/zener) for each digit as that will let me control and extinguish just the digit that I am interested in changing instead of all at the same time (it will add some more components but I think it is fun to solder). I am also making a switching power supply with a transformer. At the moment I am experimenting with winding the second coil on top of the main inductor to see if it can decrease the audible noise from the switcher. /Martin -- 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/9956a3b0-2b21-4ff1-af66-cdb87494592c%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
