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BrianG
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04.28.2007, 07:16 PM

Putting it in the freezer works too as it makes the epoxy more brittle. Just a gentle prying action breaks the connection quite easily. Whatever works...

Griffin, I realize that the cap could have had too much current, but wouldn't it have had to be multiple high current charges and discharges? All caps have the inrush of current on initial charge. From the looks of it, that cap is simply on the + and - inputs so it's not like there was an oscillator circuit on it to rapidly charge/discharge. Of course, this assumes that the batteries were connected right - which I'm sure they were otherwise there would be more issues that one cap I would think.

I still think there was something that caused this that isn't directly related to the cap, even though it looks like it suffered for it.

Are we all sure it is in fact a cap and not some sort of avalanche diode to shunt voltage spikes that are too high to ground. It does look like a cap though...
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GriffinRU
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04.28.2007, 07:57 PM

So this is the cap we talking about, right?

As for polarity and overvoltage we covered that earlier in differnt threads, if anyone interested I can explain later in different thread or via PM.
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zeropointbug
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04.28.2007, 09:38 PM

So have we come to agree that this is a ceramic cap? This would take away one explanation, as to reverse polarity, they aren't polarized as you probably know. I did the internal mod to mine, and I am sure that it's ceramic.

None of this makes any sense though, this is a tough one. :032:


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GriffinRU
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04.28.2007, 10:08 PM

Quote:
Originally Posted by zeropointbug
So have we come to agree that this is a ceramic cap? This would take away one explanation, as to reverse polarity, they aren't polarized as you probably know. I did the internal mod to mine, and I am sure that it's ceramic.

None of this makes any sense though, this is a tough one. :032:
In between, if you had one then you should better know which one.
My posts here only based on this pictures:

where capQ is capacitor under Question
capT one of tantalum caps everyone familiar with, not always with markings
and this one I am not sure if you seen this one before.

It is quite easy to identify ceramic cap from tantalum when you have it your hands or close lookup, there are couple exceptions of course, but lets not go there :)

The one under question looks more like?
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Last edited by GriffinRU; 04.28.2007 at 10:10 PM.
   
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zeropointbug
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04.28.2007, 10:18 PM

You don't think those look alike do you?

Tantalum caps almost always come with markings. I don't see why they would use a tantalum cap here, a ceramic is a better choice clearly.


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