Easy way to identify COUNTERFET TRANSISTORS!
 

The easiest way to identify a fake transistor is to weigh them on a digital gram scale. Please post weights of any output devices that you come up with. I have weighed several varieties of GENUINE Sanken TO3P's.... and they weigh exactly 6 grams. I bought a couple suspected Sanken fakes on ebay from China and will post the weight when they arrive.

Easy way to advise the counterfeiters how to improve their fakes too! You can be sure the Ebay guys follow this forum with translation software.

Fakes are a cat-and-mouse game with the counterfeiters striving to remain one step ahead. We hear of stupid fakes like the ones you refer to but I have seen MT100 (TO3Pn) and MT200 Sanken fakes with similar mass and internal construction to the originals. The difference was the die, bonding and wires.

If you really want to avoid fakes, stop going back to the same bunch of cut-rate sellers and unscrupulous local retailers. Buy from authorized agents or manufacturers since it only takes one batch of fakes to increase the cost to you several times over. :mad:

+1
I got burnt a couple times, so now I buy Power Transistors *only* from ARROW and AVNET . Period.

Might work for power transistors, but I doubt you can use this for TO-92s.

/U.

The weight is not always different, the weight here is indentical, but the function is not.

http://www.sandcastle.dk/artikler/TDA7240A.jpg

Is it not true that most fake semi's are some lesser component rebadged with the id of a popular more sought after device ??. the weight system maybe would work better with capacitors?... I bought some lm3886 from RS components you may find it hard to belive .. !! THEY WHERE FAKES !!

As much unlikely that it might be, if you can prove that they are fakes I think RS will happily take some action to fix the problem. Their customer service seems to work to me.

Good suggestion, but a little limited. I would add, together with other big distributors (just on top of my head, without particular order: Digikey, Mouser, RS, Farnell) , the own sites of the manufactrers (i.e. OSEMI). Some of them accept small orders for fair price. There you can get often some free samples, and you have the lowest probability to get fakes.
At the the end what I do not see is any advantage to buy from these unknowns on the Internet.

Where are these fakes made? I mean they're obviously not moulded together at home! So they're being mass produced in a factory somewhere who must also produce 'real' transistors and ICs too... A lot of effort is being expended just to counterfit some transistors. Wondering if there's any way the location of manufacture can be narrowed down by looking at the mouldings of the cases, materials used, a careful look at the insides etc. and working back from there? Surprised the law hasn't gotten involved in some capacity by now and instigated some kind of trace back to the manufacturers. The real manufacturers of transistors must be getting as pissed off as we are by now...

Most fakes are rebadged lesser components .. If the case fits change the nummbers.. The fakers will stop at nothing .. It was recently reported on the NEW's That there was a totally fake apple store full of fake apple goods .. Even the employees belived they where working for apple.. Just goes to show how far they will go.... I have to admit the report did make me chuckle. Just in case someone requires proof her is a link to the report

http://www.bbc.co.uk/news/technology-14503724