There are three test points in there, two for voltage rails and one apparently for a time base. I suspect the power is OK if it does power up at all (unless all the logic chips needed for display do not use it and have separate voltage rails), what about the 5HZ point? Also, if the reading is random, I suspect that the problem might be somewhere outside the boards - disconnected input socket or one of buttons not contacting.
W dniu wtorek, 31 października 2017 10:03:37 UTC+1 użytkownik Paolo Cravero napisał: > > Funny thing is that it worked when I first powered it after opening the > box it was shipped into. That's how I confirmed the bulb was not lighting > up by measuring 12 V: I got only units and decimals when varying from 9V to > 12V (20V range). > > Once the circuit was out it started misbehaving. No matter what I put in > input, it just randomizes numbers. Well that could be entertaining > nevertheless! No signs of leaks or fat capacitors. It has been serviced and > a couple of traces rebuilt. I will check traces or bad joints in case > something got damaged while on my desk. I attach two pictures of the > digital section for the curious ones (I can share other internals too). > > Still, I can't fit a full size Nixie in that space: I need the bulb or > arrange something with LEDs. > > Paolo > > > > Il 31/Ott/2017 01:25, "gregebert" <greg...@hotmail.com <javascript:>> ha > scritto: > > If I had to guess, one or more electrolytic caps has probably dried-up and > is no longer working as a capacitor. Probably a good idea to replace all of > them with fresh ones. Keep an eye out for corrosion on the PCB from leaky > electrolytics, and be aware that some probably contain PCBs (not printed > circuit boards, but highly toxic *P*oly-*C*hlorinated *B*i-phenyls). > > I always got a laugh about cost-cutting by using a neon bulb instead of a > nixie tube for the leading '1' digit. > > I bought 2 Fluke 8000 DMMs several years ago (they are LED, not nixie) > because they were very reliable when I was a technician. But they have > accuracy issues, and some of the pushbuttons dont work very well. I'll > probably give them away as-is to anyone willing to pay shipping costs. Some > things dont improve with age.... > > -- > 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+...@googlegroups.com <javascript:>. > To post to this group, send email to neoni...@googlegroups.com > <javascript:>. > To view this discussion on the web, visit > https://groups.google.com/d/msgid/neonixie-l/6ec70545-bcc4-479a-8061-16b9870932e2%40googlegroups.com > > <https://groups.google.com/d/msgid/neonixie-l/6ec70545-bcc4-479a-8061-16b9870932e2%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > > > -- 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/3c18e29b-df0e-4380-9d67-d240137a6155%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
