Beware of recent batches of fake 2N3055!

Discussion in 'General Electronics Chat' started by aromring, Dec 23, 2015.

  1. aromring

    Thread Starter New Member

    Jul 22, 2015
    20
    9
    Hi folks,
    I bought 2N3055 that strongly smell like counterfeits. On Amazon.com, of all places. Here is the video I made on how they "performed" and what tests they failed: . Here is a direct link to the product, still active on 12/23/2015:

    http://www.amazon.com/gp/product/B00KHMRKJK

    Unfortunately, Amazon has rejected my video review, twice. Thus, I had to post a simple text only review with not much detail. In all likelihood, though, this product will be de-listed, to cancel my review, then re-listed under a new link... Counterfeit electronic components are like a Black Plague, spreading fast... :(
     
    absf, Sinus23, hp1729 and 3 others like this.
  2. dl324

    Distinguished Member

    Mar 30, 2015
    3,246
    622
    Thanks for the heads up. You should complain to ST about counterfeit product with their logo. It's not their fault, but they have a reputation to protect.
     
  3. Lestraveled

    Well-Known Member

    May 19, 2014
    1,957
    1,215
    Did you report it to Amazon as counterfeit parts?
     
  4. aromring

    Thread Starter New Member

    Jul 22, 2015
    20
    9
    Good idea, thank you. I have just sent such an e-mail to a California representative of ST.
    Do you know of other hobbyist forums where I could post my warning?
     
  5. aromring

    Thread Starter New Member

    Jul 22, 2015
    20
    9
    Yes, I did. Twice. Here is my original video review:

    Don't buy - these are likely fake 2N3055!

    Buyer beware! These supposed "2N3055 transistors" are suspected fakes! See the video for justification. If video does not work, then you can use this link: . It's even confusing who sells these items: one line says "Omega Power", the other "TTL Components". Either way, if the counterfeit nature of these "components" is confirmed, then shame on whoever sells these and shame on Amazon for doing business with these people. :(

    And here is Amazon's response:

    Your review could not be posted.

    Thanks for submitting a customer review on Amazon. Your review could not be posted to the website in its current form. While we appreciate your time and comments, reviews must adhere to the following guidelines:
    http://www.amazon.com/review-guidelines

    So. I was forced to post a mundane text-only review instead...
     
  6. nigelwright7557

    Senior Member

    May 10, 2008
    487
    71
    Its hard to get original 2n3055's.
    I bought a 1980's Maplin 225WRMS amplifier with the 2n3055's missing.
    I bought in two from RS Components (excellent vendor) and my amplifier oscillated badly.
    I had to increase the VAS capacitance to stop it oscillating.
    I put one of the 2n3055's on a semiconductor analyser and its gain was very high compared to original datasheet.
    This is probably why I had oscillation.

    On my travels I see loads of forum threads about fake components.
    Personally I don't buy off Ebay or not well known vendors.
    I stick to the likes of RS Components and Farnell and I have very few problems.

    In the distant past I have bought irfp4227 mosfets off ebay and regretted it, they just blew well before they reached a high current.
     
  7. Roderick Young

    Member

    Feb 22, 2015
    408
    168
    Thanks for posting such an informative video. I feel your pain, brother. I just got some bad LM35 temperature sensors from China, which another member here analyzed and found to be NPN transistors. At least your transistor kinda sorta worked as a transistor. Has this forum done an article on counterfeit parts? I would read that with great interest, now.
     
  8. sootydog

    New Member

    Jul 23, 2011
    7
    1
    A few points from someone who used to work in the semi industry.

    You're right, I would expect a chip used for a 2N3055 to be bigger, 3.5 mm square or so. It's unlikely that chip would meet the spec. And the marking is a give away too.

    But:
    I would not expect to see anything other that it "just stuck down to the case".
    That wiki image is many years old, nobody builds them like that anymore.
    You can put any chip that meets the minimum specifications in a TO3 case and call it a 2N3055. There's no defined design or expectation of exactly what it will look like when you open the case.
     
  9. Lestraveled

    Well-Known Member

    May 19, 2014
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    It must be a strange world in China when they can purposely put a 1 amp transistor into a TO-3 case and sell it as a 2N3055 (15 amp) transistor and make a profit? What elements in China make this possible?? There is a lot of metal in a TO-3 case. The case must be worth more then the fake die they put into it. One Ebay listing sold five 2N3055 for $1.88 free shipping from China. Are their semiconductor houses so under used that it makes economic sense to make fraudulent parts?? Do the laborers pay the companies to let them work there?? I don't see how a country can continue down this path and survive.
     
  10. bertus

    Administrator

    Apr 5, 2008
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  11. #12

    Expert

    Nov 30, 2010
    16,304
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    Been there, done that. I had my transformer man build a 70 volts (rectified) transformer good for 10 amps. Alligator the transistor at collector and emitter, drop an amp through the base, and then disconnect. We were having problems called, "Isb" Current, second breakdown. The transistors would not turn off after you turned them on. My cheap Mexican boss learned not to buy in Tijuana unless he was willing to accept a 35% failure rate and pay the labor to hand test each transistor.:mad:

    (They cost a lot more labor to replace after they were built into a machine so we tested them before installing them.)

    The transistors that passed the 70 volt test worked just fine in the 35 volt power supplies. Yay! My test weeded out the clunkers!
     
  12. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    I don't see why these are so rare: right now (12/24/15 6:11 AM EST) DigiKey has some 2,875 2N3055's on their shelf for sale, and that is just one distributor.

    I used to work for a place that made military grade 2N3055's. Folks, let me tell you the wonders of getting on the qualified parts list (QPL) maintained for the government. If you get listed and the competition drops out you can charge whatever you wish for parts. They would sell these things for hundreds of bucks a piece to companies forced to buy them per archaic military specifications.

    Edit to add: Oh great, now the counterfeit 3055's of post 1 are appearing in my sponsored adds on every other web page I visit.
     
    Last edited: Dec 24, 2015
    #12 likes this.
  13. ISB123

    Well-Known Member

    May 21, 2014
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    Because most of the industry has moved onto TO 220 packages.

    TIP120, 2SC5200, TIP107, TIP142 ,TIP36C...
     
  14. bertus

    Administrator

    Apr 5, 2008
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  15. debe

    Well-Known Member

    Sep 21, 2010
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    Since looking at this article I too get adverts for the dodgy transistors.
     
  16. JohnInTX

    Moderator

    Jun 26, 2012
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    Not me. Firefox with AdBlock Plus.
     
    #12 likes this.
  17. ISB123

    Well-Known Member

    May 21, 2014
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    I could make a list of eBay sellers that I use for ordering components.
     
  18. #12

    Expert

    Nov 30, 2010
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    We already have that Thread in the Electronics Resources forum.

    Wait, not the eBay sellers. You could be helpful with that part, just put them where we know where to find them (in the E-Resources forum, 'where to buy' thread.).;)
     
  19. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    Nice. Installation complete.
     
  20. #12

    Expert

    Nov 30, 2010
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    Same here.
     
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