Thanks! I looked up that chip and found a lot of useful info. Jim
On Wednesday, September 5, 2018 at 12:47:21 PM UTC-6, [email protected] wrote: > > On Wednesday, September 5, 2018 at 7:50:55 AM UTC-7, Jim KO5V wrote: > >... My guess is that this is more than just adding in a circuit with a > battery - a frequency source may also be needed. > > If you want an integrated solution instead of adding an outboard UPS, > consider this: > > All my ideas are stolen from the Cal-Tex CT7001 clock/calendar chip. They > recommend using a battery to keep the logic alive. > > Their clever idea was to use the MUX oscillator to help keep time when the > mains were out. You could emulate this idea by building a 60 Hz source > that was phase-locked to the line frequency (and very close to 60 Hz > free-running), possibly based on a NE565 or NE555. This could also improve > the time keeping in normal operation, since the clock would be more immune > to the noise spikes on the power line (my clocks based on MM5531x chips, > TTL logic, and CMOS logic all ran slightly fast and I blame that on > counting excess noise pulses). > -- 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 [email protected]. To post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/c3e0f2d0-ec3b-4a41-98fb-66a3d029013d%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
