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Electronic component identification

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cypeng

cypeng

Electrical
Jan 8, 2008
1
Hi,

I have come across a faulty component that needs to be replaced but I can't identify what it is and thus where I can buy it from. It is disc shaped with 2 pins and on top it writes 'K391 J8'. Any help is appreciated.
 
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The 'J' likely indicates 5% tolerance. Not sure what the '8' signifies.

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To correct itsmoked - its probably a 390 pF capacitor.

Otherwise it would be quite a hunk of ceramic!

Always gotta watch those uF, nF and pF Keith! I know what you meant to type!
 
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I'm struck by the term faulty and can't imagine the probability of a 390 pF cap failing. How many leads, 3? Could this be a 2SK391?
 
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Yeah! I figger out 390pF then write down uF.. ??
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I rarely use any ceramics less than 0.01microfarads so I guess it's just finger muscle memory.


I would agree a 390pF cap is probably one of the most reliable components you'll ever come across.

Keith Cress
Flamin Systems, Inc.-
 
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Scotty,

Normally I would agree with you on the 5% thing, but the fact that the J is combined with an 8 makes me wonder if it's not a different type of code rather than tolerance. If the component isn't a cap, that would be likely...

Dan - Owner
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Hi macgyver,

The 'K' could be a 10% tolerance code too, but it is in a strange place. I wonder if we'll get a photo of this mystery component?


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could very well be a varistor, and the J8 the physical size range, or energy rating. If it is either red or blue this makes it even more likely.

How large is it and what color? A 390pF ceramic would probably be quite small.
 
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Hi

That is 390 VDC, VDR( voltage dependent resistor)in case of defective it must indicate short circuit, if its tested with multimeter as a resistor
 
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After nearly three months and no photograph I think the OP has lost interest. We're all guessing, and the OP seemingly doesn't care any more.


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Maybe he died while testing the part, following our misguiding tips :D
 
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