Glad removing the heatsink seemed to solved the issue. It's interesting it has this behavior next to the blanked out tube: does it have the same behavior when using 24 hour mode? (if it has such a mode, or any other mode where it doesn't blank out any tubes). Blanking out a single tube (of a pair) is not really recommended by switching off only the cathode driver (the chip driver). It should be done by switching off the anode driver instead, but in this case you could only switch off a pair of two tubes that way (since this is a 3x2 multiplexed clock - each pair of tubes has a single, shared anode driver (the transistors)). The driver chip may be exposed to higher voltages this way, and this could lead to it failing sooner.
However, in your case it seems to be showing the seconds in what I assume is the hours tube? So, this seems more like a timing issue to me, where the anode is switched to the next pair before or right at the same time as the cathode driver was switched to the next digits. To do this right, there should be some dead time between switching off the anode and switching to the next anode (see a recent (a month or so ago) thread in this group about a similar problem). Still - if this is a new issue (and you didn't change the firmware), that would also be strange. Are you sure it wasn't always like this? On Saturday, March 28, 2015 at 10:11:05 PM UTC+1, MichaelB wrote: > > I would try replacing C6 again with a known good part and leave the clock > out of it's case without the heat sink and see how it does. This is the > exact syndrome that mine exhibited twice on the one clock until I opened up > the case and dropped the voltage and replaced C6. Then add a heat sink ,if > you must, a la Nick's (Pramanicin) picture above and raise the voltage up a > little. > > Seriously doubt you have bad driver chips. Those things are pretty bullet > proof > > On Saturday, March 28, 2015 at 1:37:48 PM UTC-7, Kiran Otter wrote: >> >> Yes, it is. I took that video after removing it. I've also noticed the >> same effect in the minute digit. It also follows the seconds. >> >> I realize it's pretty faint, but this is the best it's been with the two >> driver chips I have in there now. With another pair, the left most tube >> constantly displayed a digit based on the 10s of seconds. This is why I >> think the drivers are a bit wonky. >> >> So far both M1 and U1 are around 105-108F. I'll have to check it later >> when it's after 10pm and all 6 digits are in use. >> >> Kiran >> > -- 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/4beca468-f4a4-4997-a1f3-1cf18cc6c2fb%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
