Home › Evil Mad Scientist Forums › Larson Scanner and Menorah › Love the Mega Menorah 9000! … but might have overheated mine? › Re: Love the Mega Menorah 9000! … but might have overheated mine?
Great debugging suggestions! The connectivity behavior of both buttons is exactly like you described, so now I’m convinced that those switches are both fine. The multimeter shows continuity between a couple of adjacent pairs on the IC, so that must be my problem! There are no solder bridges that I can see, so I’m betting that there must be a bridge or two hiding under the chip on the top side of the board…I do tend to feed the solder so that the blobs go through the top side, so there’s probably a short hiding up there somewhere. :)
I also measured the resistor values for the heck of it (they were all correct when I started the kit, but I wanted to see if any of them changed when the circuit overheated), and R6 is only around 10 ohms or so… definitely nowhere near 1.5k. I have a few spare 1.5k resistors lying around from a past project, so I’ll try swapping one in for R6 when I go in to fix the joints on the IC. I hope to report back with good news when I’m done with those fixes!