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Got a Bulbdial kit as a gift, and it looks awesome :D
I am having a problem during the blue ring testing phase. About 1/3rd of the LEDs do not light up during the test. Using my Arduino as a 3.3v power source, and a 330Ohm Resistor to keep the LEDs from burning out, I tested each LED while it was soldered in place, and I can confirm that the LEDs are not burned out. I tried this while the power to the clock was off and they would each light correctly.I checked for shorts, solder that went between two connections it should not have, etc, and I cannot see any issues visually…As I was soldering in the IC, I was worried that I might have done it too quickly as it got warm (not at all hot, just a bit warmer than skin temp). Could this be causing this behavior? I can specify the exact LED positions if it helps, but D12, D32, and D42 are a few that are not working.Oh, another weird thing I noticed, I have my Arduino running a simple LED lighting circuit, but when I plugged in the spare blue LED that came with the kit, it wouldn’t light (although it worked fine when hooked straight to power and a 330 Ohm resistor…?). Do these LEDs have a specific minimum voltage they must reach in order to function?Thanks for your help, hope we can get this working… :(First off, the IC is fine– if it breaks, it will break completely.
Second: the green and blue LEDs won’t light reliably until you give them ~3.4 V forward voltage. You shouldn’t expect outputs from an Arduino running at 3.3 V to be able to drive them directly.Problems of the sort you are describing are due to an accidental connection, a broken connection, or a damaged LED– they can sometimes be damaged by heat and/or strain on the legs during installation.D52 and D62 are also in the group that you are describing– check those five LEDs to see if any of them appear weak or shorted to lines that they shouldn’t be connected to. Test also that each is actually connected to the two lines that it is supposed to be connected to– test LED6 to LED2, for example, to see that D62 lights.It sounds like there is no connection between the line LED2 and the rest of the circuit. Check the soldering at resistor R2, and also at the IC, on the side that faces R2.
Do you have a multimeter that you can use to check for a connection between two points? If so, I would check to see if there is a connection from the pin of the IC (it’s pin 23) to resistor R2, and to check to see if there’s a connection from R2 to the relevant pins of the LEDs.
If not, try visually tracing from R2 to the IC (the trace is visible on the bottom side), and to D25 on the top side. You can also try adding a wire directly (temporarily soldering a wire, for example) from the right side of R2 to the pin of D25 there.If you would like to send the board to us, for us to look at it, please contact us through our store contact form ( http://shop.evilmadscientist.com/contact ). [For what it’s worth, people take us up on this offer on a regular basis. In almost all cases, we find that soldering one or two missing solder joints solves the problem.]Lead free solder is just fine, provided that your iron gets hot enough to melt it. Newer soldering irons do operate at a higher temperature; if you are using an older iron with lead free, it can sometimes be a little challenging.
(And, if your solder is narrow gauge, flexible, and is sold as solder at radio shack, it probably has a reasonable flux core, whether or not it’s rosin based.)
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