Counterfeit 2SC1106's ?

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Hi,
Bought a batch of 2SC1106's and I am pretty sure I received counterfeit products.

I took readings and they look bad. I even received continuity "beeps" on the last 2 tested (T4 and T5).

I attached pics of the transistors that I received as well as a spread sheet with the readings I received.

Everything that I have learned indicates these are all bad but I would like a second opinion as I am going to return these and post the supplier but before I do, I want to be sure.

Thanks in advance
Jeff
 

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The readings definitely look bad... not sure whether they're actually counterfeit, or just bad transistors. I assume they were sold as new?

Usually when I hear about counterfeit transistors, they're just cheap transistors repackaged/remarked to look like expensive ones... but they fail very quickly in use. But they would pass your simple diode test. I guess maybe they have a bunch of dead bottlecap transistors in a factory somewhere, and just relabel them with expensive P/Ns instead of actually making the counterfeits.

It'd be interesting to cut them open and see what's actually inside.

DogP
 
When I saw that uneven - smudged lettering, I was worried from the start and that is the reason I tested them before anything else.......
 
Where did you get them, EBay ?

I bought some 2SC5300's off Ebay last year from a reputable
seller. They didn't even read like transistors (tested them with
meter, scope and component tester).

The seller gave me a refund and insisted he's sold many of them
without problems however these were definitely counterfeit.

JD
 
I would test the dc resistance of the suspect transistors with an analog meter. After that, I would also test them with my Huntron Tracker component tester.
 
Here is a pic of a known good working that I have, you can see the quality difference of the printing on the component......
 

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These were purchased from Arcade Parts and Repair and I have contacted them regarding this situation. I am awaiting their response.
 
I would test the dc resistance of the suspect transistors with an analog meter. After that, I would also test them with my Huntron Tracker component tester.

Ken,
I do not have an analog meter nor a Huntron Tracker component tester ... :(
By no means am I an expert in anything, let alone electronics but all my past experience testing transistors while troubleshooting leads me to believe that this entire batch (5) are bad, especially the 2 that read continuity, (beeped).
Jeff
 
Peter from Arcade Parts and Repair got back to me immediately and apologized for the problem and is sending out replacements (made in the USA!).
Excellent customer service!
 
What meter are you using to do the test? What type of batteries does you meter take?
 
I would test the dc resistance of the suspect transistors with an analog meter. After that, I would also test them with my Huntron Tracker component tester.

this is exactly what the huntron tracker excels at, sometimes i wonder why i have it but then when it come to testing transistors and finding shorts including internal i/c failures its awesome and i will hang on to it
 
What meter are you using to do the test? What type of batteries does you meter take?

I used two different meters:
-Fluke Scopemeter123 uses a rechargeable battery pack but I have it plugged in
-Fluke 83V with a 9 volt battery (AFAIR)
Both gave almost exact same readings....
Why does that matter?
Jeff
 
I used two different meters:
-Fluke Scopemeter123 uses a rechargeable battery pack but I have it plugged in
-Fluke 83V with a 9 volt battery (AFAIR)
Both gave almost exact same readings....
Why does that matter?
Jeff

I'm just trying to rule out some variables. Some meters only use 2 AA batteries. That's only a total of 3v. Those meters do not have enough power to "push" through some PN junctions. Mostly they have problems with power transistors set up in a darlington pair because the voltage drop to get through the PN junctions is about half the total power of the meter. Just not enough oomph. Since you tested them with a meter that uses a 9v battery, your reading are most likely correct. Sucks you got a bad bunch.
 
Bad bunches happen, even from the best.

I had to replace all the transistors in a juke box because of a bad lot.

Stuff like this can sit around for years, and you don't know you have a problem until you test them out.

You really can't go by the screening on the device. Lean manufacturing means cheaper screens. If it's legible, they'll use it.

Most stuff I have seen that is counterfeit are the DIP chips. You can use a solvent to clean off the old logo, and screen on a new one. There generally isn't enough money in bottlecap transistors to make it worth the effort.
 
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