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Removed / Tested (original caps) from working CC MB = Results.
Posted by: uniserver on 2015-06-19 08:14:41
IMG_2099.JPG

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KEY:

1. Position

2. Printed Cap Value

3. Tested / Actual Value

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C2

100uf 6.3v

103.7 uf - 9.5 esr

C3

100uf 6.3v

103.8 uf - 2.0 esr

C4

47uf 16v

OPEN

C5

47uf 16v

52.68 uf - 44.0 esr

C8

10uf 16v

10.42 uf - .59 esr

C6

47uf 16v

OPEN

C9

47uf 16v

DIODE 4.54v C=0nf

C10

47uf 16v

32.33uf - .27 esr

C11

47uf 16v

OPEN

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all these caps were leaking, regardless this was a working MB.

so goes to show how bad the caps can be and still have a temporally working mb.
Posted by: Elfen on 2015-06-19 08:48:38
Interesting. I figured that a bad/leaked cap would be either open or shorted. But it still working on some is interesting.
Posted by: Juliet Elysa on 2015-06-19 11:15:05
OK, noob question. 😀 What does "open" mean in this context?
Posted by: uniserver on 2015-06-19 11:28:25
open would mean the same thing as if a cap was not there/missing. 
Posted by: Schmoburger on 2015-06-22 14:30:37
Yep, open in electrical terms means open-circuit... essentially this means there is no electrical conductivity between point A and point B in a circuit indicating the circuit is broken due to a failed wire, trace, joint, or component, or in the case of a component such as a capacitor, the component no longer has electrical continuity (as it has failed) and may as well not exist.

I find these results unsurprising but nonetheless fascinating to see put to paper. 🙂

Posted by: Unknown_K on 2015-06-22 22:18:59
I have one of those little battery powered ESR meters (best $22 I ever spent, different model then yours). Problem is most caps are in parallel in a circuit so you still have to remove them to check which ones are off. When caps leak their readings start to wander all over the place, depending on the circuit they might work or might not or worse work some of the time causing headaches. Mostly I hate them leaking and taking out traces or other close chips (same with old leaking motherboard batteries).
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