I'd start with 6.8K anode resistors (assuming 3,6 to 7.3 is your target range) and see how it works out. Keep a close eye on it for a couple of months, if its running 24/7. If the current is too low, you'll start to see partial illumination on the the digits over time. Then you need to increase the current. Its easier to do this by tacking resistors in parallel, to existing resistors, than by complete replacing resistors.
On 74141s any code over 9 will keep all cathodes OFF. So, you can blank it that way. There is a possibility of leakage as the parts age. This will show as "ghosting". Again, this may not show up right away. Only time will tell. Since you're already switching the anodes, why not use the anode circuit to blank the display. Its only a software modification. Also, since you're muxing, the supply voltage will be higher. Nominally 200V, so any leakage problems, will show up earlier. On Sunday, March 18, 2012 3:31:22 PM UTC-7, Cobra007 wrote: > > If you take 7.3k resistors rather than 3.65k resistors, the tubes will > only be 6dB less bright which is not significant. If that increases > tube life, I would say, that is the better choice as you pointed out > already. > > For blanking, I think Adam means to send a hex number (0x0A) to the > 74141 (D=1; C=0; B=1; A=0). According to the datasheet, this would > lead to a correct blanking of the tubes. > > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/7s_AhKwZ5TQJ. 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.
