On Friday, June 19, 2015 at 1:55:55 PM UTC-7, wb9jfr42 wrote: > > Has anyone built a clock using MM5309 or 11 chip with nixie tubes > Using BCD to a 74141 but don't seem to be able to multiplex > > i would like to use the chips that i have had for many years > > Thanks > jerry > I would steal ideas from two places.
For your cathode drivers, I would use the circuit from Figure 6 of the MM5309 data sheet ( *http://connect.enterprise.online.fr/mm5313D/mm5309-5311-5312-5313-5314-5315.pdf* <http://connect.enterprise.online.fr/mm5313D/mm5309-5311-5312-5313-5314-5315.pdf> ) on page 1-7 to interface the ~BCD outputs to TTL. You might have to invert these with a 7404 to get the correct data polarity for your 74141. To drive your anodes, follow the ideas from the article on page 70 in the July 1976 issue of 73, “Behold the Giant Nixie Clock - using a minimum of new parts” by Jack Grimes, W4LLR ( *http://www.tube-tester.com/sites/nixie/dat_arch/B-7971.pdf* <http://www.tube-tester.com/sites/nixie/dat_arch/B-7971.pdf> ). He uses high voltage pnp transistors (like the 2N5401, although I used surplus TO-220 transistors with a nominal BV of about 300V) with the emitters connected to B+ (about 180V), and the bases capacitively coupled to the digit-select outputs. Since this was designed for the MM5314, it should work just fine for your MM5309/MM5311. I modified these ideas to work with a CT7001, and built three clocks. All are still working 24/7 after more than 35 years, with the only failure due to an underrated surplus power transformer. -- 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/9bfdf079-d00e-4b23-83de-adc779b0968a%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
