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Washington
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I was looking for some 2N2222s on ebay.
I know there are alot of good deals from Hong Kong and China on ebay for many things.
But 50 2N2222s for $1.50 (http://www.ebay.com/itm/50PCS-Transistor-MOT-ON-TO-92-2N2222-2N2222A-/270854651567?pt=LH_DefaultDomain_0&hash=item3f1031feaf) seems way too good to be true.
Has anyone had experience with these?
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Perhaps from the reject bin?  After manufacture transistors are sorted into groups by gain and performance, the duff ones have to go somewhere...  These might easily be unbranded/rejects.  Best avoided if you want reliability.

At that price you might want to try them out anyway and see if they are actually up to spec - if so let us know(!)
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I bought some, at this price it's worth the risk.
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I've bought a handful of 2n3904 from Tayda Electronics at $0.01.

I haven't measured hfe, but I have never had any problems with them either.
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I've just put an order in for 30x 2SD965 transistors from a hong kong based eBay seller... remains to be seen whether they'll do the job, but for my chosen application (very small HV inverter/cap charger similar to camera flash), I will probably accidentally kill quite a few of them. So, being slightly off-spec doesn't bother me very much. I say, go for it anyway. If nothing else, having some cheap "throwaway" bits might be handy for R&D purposes where things might accidentally get blown up.
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...Makes me think of the phrase, "Penny-wise and pound-foolish".

Is the potential trouble worth the risk?   Or i guess I should say, is saving a few cents worth the potential risk?

This is one of those gambles where the odds of winning (finding good transistors) are very-high, but what you win is very-small.   And although the chances of loosing are very-low, if you do loose you can loose big... maybe lots of frustration and wasted-time, maybe even burn-up some other good-parts.   This the opposite of playing the lottery, where your chances of winning are low, but the cost of loosing is also low.

Even in "big production" where the "pennies add up",  it's not worth the gamble, because if 1% of your products end-up with bad transistors, it's going to cost you more than you've saved.

Just for example, where I work (a small company), we almost always throw-away any parts that we've un-soldered.   If it turns-out that part wasn't the problem...  Maybe it's a different part, or maybe it was solder-short under the part we removed...  We replace it with a new part from stock.   Parts are cheap (compared to the labor) and re-using a part is just not worth the trouble.   If it's an expensive part, it's probably something like a 100-pin IC.   In that case, a few of the pins are likely to be bent, and again it's usually not worth the extra work & risk of re-using a part.
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Washington
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...Makes me think of the phrase, "Penny-wise and pound-foolish".

Is the potential trouble worth the risk?   Or i guess I should say, is saving a few cents worth the potential risk?

This is one of those gambles where the odds of winning (finding good transistors) are very-high, but what you win is very-small.   And although the chances of loosing are very-low, if you do loose you can loose big... maybe lots of frustration and wasted-time, maybe even burn-up some other good-parts.   This the opposite of playing the lottery, where your chances of winning are low, but the cost of loosing is also low.

Even in "big production" where the "pennies add up",  it's not worth the gamble, because if 1% of your products end-up with bad transistors, it's going to cost you more than you've saved.

Just for example, where I work (a small company), we almost always throw-away any parts that we've un-soldered.   If it turns-out that part wasn't the problem...  Maybe it's a different part, or maybe it was solder-short under the part we removed...  We replace it with a new part from stock.   Parts are cheap (compared to the labor) and re-using a part is just not worth the trouble.   If it's an expensive part, it's probably something like a 100-pin IC.   In that case, a few of the pins are likely to be bent, and again it's usually not worth the extra work & risk of re-using a part.
In my case, I am only a hobbyist and do not make anything in production.
That said, it is indeed a gamble of frustration and wasted time.
Still its worth a shot for that price.
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Quote
In "big production" ..., it's not worth the gamble
That's true (or it should be, at least).

But if you do not count labor cost in your hobby, it's perhaps different.
After you checked the content of your surprise bag and verified it fits to your needs, you have added some value to those cheap parts.

Quote
what you win is very-small
1.50 $ for 50 transistors isn't that cheap, IMO.
Assuming you cannot really rely on the specs, but 90% will "behave like a transistor" and 10% die during the test
... one should get 30 * "2N3904 or similar" for a similar price from a reliable source, IMO ...
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Washington
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Quote
In "big production" ..., it's not worth the gamble
That's true (or it should be, at least).

But if you do not count labor cost in your hobby, it's perhaps different.
After you checked the content of your surprise bag and verified it fits to your needs, you have added some value to those cheap parts.

Quote
what you win is very-small
1.50 $ for 50 transistors isn't that cheap, IMO.
Assuming you cannot really rely on the specs, but 90% will "behave like a transistor" and 10% die during the test
... one should get 30 * "2N3904 or similar" for a similar price from a reliable source, IMO ...
$.03 each seems pretty good to me.
If it can be verified that they are acceptable, then it seems like a good deal.
It appears to be worth a shot for that price. And if they are no good, then I am only out $1.50
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Avoid throwing electronics out as you or someone else might need them for parts or use.
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Resistors for LEDS!

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I received my 50 transistors last Friday. I just checked 10 of them with my multimeter, they all have a HFE between 215 and 240. I think that's rather good smiley
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I'm not surprised.  The supplier I buy thousands of semiconductors from in Shenzhen knows a lot about the shady-market and he avoids it.  And his prices are almost as good as the guys on the street and the hole-in-the-wall bargain places.   

Fact is there is LOTS of surplus production capacity in good factories and we are the winners...

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I usually buy my more common semiconductors off ebay, and haven't had a problem yet, maybe luck idk but its been a while with no problems
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