Hi again, Good to see the 100k improves things, leakage either is or contributing to the isse then, maybe the base of Q9 is capacitvely coupled to something, I dont know why the 10k messed things up, 10k isnt a low enough resistance to upset the pic, if you pull too much current from the pic and force its current limit into operation then you can have all kinds of issues with the good old read modify write problem. Maybe something else odd is going on there. Also I've had issues with nixies and led's for that matter when I've modified the data on the port controlling the cathodes (segments) before I've switched anodes, my more recent programs blank the display then switch the anode, then write the new value for the cathodes. I think I probably misunderstood your schematics, I cant access them now the forum has changed but from what you describe it sounds ok. R.E. the 32.768kc crystal and timer 1, I have a hard drive pendulum clock on my desk now, the display is on the end of the pendulum, the accuracy is very good, 3 secs per week, using a 32kc xtal is a good idea, my code just polls the bit of timer 1 that changes at 1hz, good power supply decoupling is essential and so's the 30pf or so stability caps for the xtal.
On Friday, 7 September 2012 15:39:02 UTC+1, Ron Schuster wrote: > I've built a 4-digit IN-17 nixie clock based on a 1x4 mux design. It uses > 4 neon lamps, 2 for the colon, 1 for the PM indicator and 1 for the Alarm > On indicator. I have a small problem where I see a dim flicker in the lamps > that are supposed to be off. They are driven as part of the nixie > multiplexing circuit. One side of each lamp is tied to one of the digit > anode drivers. The other sides are tied together and pulled to ground > through one common MPSA42 "cathode" driver. I think I have sufficient > blanking time between the digits. Each digit is on for 1 ms and the > blanking time between digits is 100 uSec. The nixies are showing no > ghosting at all. Any help in figuring out why my lamps are not turning > fully off would be greatly appreciated. Schematics are attached. > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msg/neonixie-l/-/hOS4OFkoKfsJ. For more options, visit https://groups.google.com/groups/opt_out.
