At 7:30 AM -0800 1/9/10, Lux, Jim (337C) wrote:
I can't help wondering if you go do better than the 4 bit counter:4-10 decoder:10-7 decoder. Yeah, simple diode matrices in an AOI configuration are easy, but surely a bit of work (as in digging up archaic designs) could find a "lower part count" approach. Time to use that Karnaugh map.
If they had used proper Nixies instead of those awful 7 segment LED displays, then they could have used the same circuit in the 5245 and gotten the job done with 8 transistors and 8 neon lamps and some CdS photoresistors per decade.
My twin brother built a clock out of some old Beckman hollow-state counters... http://www.selectric.org/tubeclock/index.html -- --David Forbes, Tucson, AZ http://www.cathodecorner.com/ _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
