Diode identification

Discussion in 'General Electronics Chat' started by styo, Aug 6, 2016.

  1. styo

    Thread Starter New Member

    Aug 6, 2016
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    Okay new to site but looks like a good place to go for info. I'm an amateur electronics geek and am in process of a tv repair. Ran across a diode in the lamp circuit that's got me stumped (easily done). The p/n on the diode is Kiv 227 with over scores like an underscore (_) over the 2 and 7 in the part number. Can't locate this part number on net and it shows bad with the normal diode test....but so does the new one...I bought a kit with the replacement parts in it so I have a new one (kiv495 with over scores over the 9 and 5) but doesn't make sense to me. Someone out there has ran across this i'm sure. Thanks
     
  2. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Welcome to AAC

    Show us a picture of the diode
     
  3. MaxHeadRoom

    Expert

    Jul 18, 2013
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    So if they do not test as a diode, (presumably you did NOT use the Ohms range on a DMM?) what makes you think it IS a diode?
    Max.
     
  4. styo

    Thread Starter New Member

    Aug 6, 2016
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    20160806_112242.jpg 20160806_112242.jpg 20160806_112308.jpg 20160806_112500.jpg
     
  5. styo

    Thread Starter New Member

    Aug 6, 2016
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    Here is the pictures requested. Tested diode with diode tester AND ohms range on Fluke 87. Thanks
     
  6. AlbertHall

    Well-Known Member

    Jun 4, 2014
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    I couldn't find anything with those numbers either. But I did find some components with numbers beginning with KIV and they were SIDAC devices (bidirectional breakover https://en.wikipedia.org/wiki/DIAC) which look like diodes but will appear open circuit on a multimeter.
    Any takers for this theory?

    Edit: not so sure having seen the picture - why the coloured band?
     
  7. MaxHeadRoom

    Expert

    Jul 18, 2013
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    What did the Diode test range show, both directions?
    Usually sidacs show a bar at each end.
    Max.
     
  8. R!f@@

    AAC Fanatic!

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    can u show us the part where the diode is located.
     
  9. styo

    Thread Starter New Member

    Aug 6, 2016
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    20160806_155955.jpg There she be.
     
  10. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Shows a regular diode symbol, is there any more reverse engineering you can do to see how it fits in with the rest of the circuit?
    Max.
     
  11. AlbertHall

    Well-Known Member

    Jun 4, 2014
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    If it is a very high voltage diode it might actually be multiple diodes in series, which again would o/c on a multimeter?
     
  12. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Could be part of a snubber
     
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