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Hello! I’ve built a few of the bulbdial clocks already but haven’t come across this issue before and wondered if you could help me? On setting up the Blue LED ring, there are a couple of LED’s that seem to flicker with another..for instance D35 causes D34 to flicker a little..I’ve checked all the solder joints, checked the microcontroller (by swapping out another chip, problem still persists) and am wondering if there’s a micro short somewhere that I can’t see…any ideas where I should look?
Many thanks for any assistance you can provide!Cheers,NickI have seen my share of bulbdial oddities– we’ve learned to help debug all of the different things that can go wrong –but I can’t recall seeing anything that someone might describe as “flickering.” Can you say a bit more about exactly what it is that you’re seeing?
D35 and D34 do share a line in common, which is the LED5 signal, originating at the right side of R3. If one or both of those LEDs is electrically bad, it could (I suppose) cause something like this.I’d also suggest carefully checking the area at those two LEDs and around them for possible solder debris such as actual little bits of metal or excess solder flux. And, try stressing the LEDs mechanically (just a little push– not enough to rebend them) to see if that affects it.That’s odd; it definitely sounds like a bad connection or bad LED type of problem.
You might consider putting it into the “manual” LED alignment mode, to see if you can leave just that one LED on for a while and observe its behavior as you tap on stuff.If it’s sensitive to capacitance, it could be that there’s an issue with the capacitors on the board– in which case a small change in external capacitance could cause a large shift. Check to make sure that all of the caps are in the right places, with the right orientation (for the big electrolytic), not cracked, and soldered cleanly. And again, see if you can stimulate a failure by tapping or prodding any particular component. Try to use something like a plastic pen to tap them, to minimize the capacitive issues.
My best guess is that there’s a damaged LED that’s not acting like an LED. But yes, please contact our shop directly about returning it for examination and repair.
We did receive the board, and found that several LEDs had failed– either not lighting up or lighting up, but somehow connecting two of the LED lines together. We swapped those out, and it seemed okay, but on letting it run a little longer, we’ve found that a few of the others are now flickering or otherwise. And, I must say that we have _never_ seen anything like this before. (The Bulbdials at our shop are running fine after years…)
We can keep replacing the LEDs until we’ve got them all, but I’m absolutely lacking any kind of explanation about what could have caused this. Is there anything “unusual” that you might have exposed the circuit to? (I don’t imagine there is, but again, I’d really like to get to the bottom of this.) Can you say what kind of soldering iron you use? The other solder joints look good, but I am curious if there could have been some electrical damage.Well, it was worth asking. ;)
One way or the other, we’ll get you taken care of– I’m just hoping that we can understand the failure mode, too.
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