| Electronics > Repair |
| BK Precision 2120 trace issues |
| << < (15/36) > >> |
| bdunham7:
OK, let's try this. On the picture I've attached, can you confirm that your board looks like this, more or less? I've illustrated where the +260V point is, that is also the L801-802 junction. The A side of L802 is connected to that, then the PCB trace on the B side of L802 goes under and around it back to the other B, which is the B side of R839. Then the C side of R839 is connected to D1. So when you measure from A to C, you should get about 15K, which is the combined resistance of L802 and R839. Apply the same logic to the other side. So where are you seeing the 5.3M ohms? |
| vexatag:
That's about what my board looks like, yes. I'm seeing 5.3M ohms from L801 A to R838 B and C. (L802 A to R389 C gives the normal value of ~15k, I was measuring from L801 because it's more convenient to clip to) |
| bdunham7:
Well, there's your problem. Or at least 'a' problem--I can't promise you there won't be more! :) So if L801 measures 7-ish ohms and R838-B measures 15K all the way to D2, then measure the trace (from B to B) between L801 and R838. There must be an open circuit there somewhere. If you can't easily see the problem but you can confirm that there is not continuity between the two B points, you can run a jumper wire as I've drawn it. Just tack on a wire to the component leads--it's called a bodge wire. |
| bdunham7:
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| vexatag:
Hmm, this might be the problem :-DD I'll try cleaning these joints up a bit first, see if that helps. |
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