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Electronic component identification

thread797-206445

Electronic component identification

Electronic component identification

(OP)
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.

RE: Electronic component identification

It's probably a 390uF ceramic capacitor.  Voltage?

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Electronic component identification

The 'J' likely indicates 5% tolerance. Not sure what the '8' signifies.

----------------------------------
  
If we learn from our mistakes I'm getting a great education!

RE: Electronic component identification

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!

RE: Electronic component identification

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?

RE: Electronic component identification

Yeah! I figger out 390pF then write down uF.. ??

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.- http://www.flaminsystems.com

RE: Electronic component identification

BTW: I do use some 10uF ceramics on a regular basis.  They're small SMT parts no less.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Electronic component identification

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
http://www.Hi-TecDesigns.com

RE: Electronic component identification

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?
 

----------------------------------
  
If we learn from our mistakes I'm getting a great education!

RE: Electronic component identification

I think that 390 Volts VDR,

RE: Electronic component identification

390V varistor?

RE: Electronic component identification

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.

RE: Electronic component identification

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

RE: Electronic component identification

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.
 

----------------------------------
  
If we learn from our mistakes I'm getting a great education!

RE: Electronic component identification

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

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