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

    Distinguished 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

    Distinguished 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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