Alrighty, I got the C3 and C4 HV circuit capacitors switched out (the closest quivalent for the C4 were a considerably higher voltage rating, 35V vs 16V. The C3 I found was identical, but a much larger metal-film version rather than electrolytic). I also re-flowed all the solder connections in the HV circuit components left in place. I don't *think* I'm changing anything, but the following appears different:
-The die-off of the circuit seems to happen a bit faster with the new capacitors (it reverted when I replaced the new caps with the better-fitting originals) -The die-off of the LEDs does not occur when the IC2 board is not installed (circuit just stays lit, but still not generating high voltage) I checked all the diodes, and they are still blocking current the way they are supposed to (can't measure the figures, though). I also checked each soldered connection to the next component in the chain, and nothing in the HV circuit is open circuit (bad solder joint/etc.). Looking at the diagram, I don't think I can isolate the HV circuit from the rest without removing a bunch of components for the LEDs and nixies, so I'm officially at a loss for the next step in troubleshooting. Even if I had access to a scope I'm certain I don't know how to use it. I'd obviously buy another 70$ kit before a 300$ scope, at least until that one cooks, too. I *think* the fault lies outside the HV circuit (but connected to it, thus draining its voltage output to 12V), or I've managed to cook the IRFD220 again (which would be surprising, since I took even greater care to solder it without overheating this time, and the first go-around actually work until the short), or the IC2 chip is nuked and cannot activate (but I'm more inclined to think the lack of a high voltage at its sensing input is the cause for that) TCB -- 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/b97e0a4e-c6ee-42d8-90b3-f14a7f0cc6c4%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
