Fake *******ING "MOTOROLA" Transistors

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Re: Motorola MJ15024

For Motorola MJ15024/MJ15025 transistors, MOT dont produce for a long time.

So MJ15024 you got you may really from MOT but it must be USED that got from old PCB if it has damage inside.

Better to buy ON brand now with 07+ or 08+
Gary
Mpole said:
Hi everyone,

I need your help. I bought some Motorola MJ15024 transistors.

I think they are genuine Motorola. But aslo I am not sure. I took some pics. There are some damage inside. Because, I could open it via drill only.

http://img.photobucket.com/albums/v170/muffy1063/IMG_4532.jpg

IMG_4533.jpg
 
I'm jumping in a little late on this thread, but I saw that about 10 years ago while the discussion was very active that a pic based project was mentioned to have a good set up to test parts for QC and detect the fakes.
However that part of the discussion didn't go much further afterwards and I didn't see anything about the development for such a tester.
Has that idea been put into practice since then?
If not, I think it's still a damn good idea and it deserves attention.
I would be very interested myself in making such a device tester, and perhaps it might even be practical to add one more feature, that would also contribute to bust the fakes, while at the same time do something some of us would really like to do, which is to do a non-destructive second breakdown test.
I am about to get a pickit and a few pic chips. Probably not the best pic chips suited for such an application, but the suitable type should be easy to get.
Perhaps linking this tester to an arduino and send the result data to a computer would be great.
 
Sorry, I know this is an old thread, but I had to reiterate what I said previously. If you can manufacture a semiconductor, why the Hell not make it a quality one?? Would you not gladly, in retrospect, shell out 10 bucks for a matched pair of 2sk170, and it's other? The confidence of the consumer is shattered. Does that make good business sense?
 
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Sorry, I know this is an old thread, but I had to reiterate what I said previously. If you can manufacture a semiconductor, why the Hell not make it a quality one?? Would you not gladly, in retrospect, shell out 10 bucks for a matched pair of 2sk170, and it's other? The confidence of the consumer is shattered. Does that make good business sense?




I can relate to that.
As a servicer for many years, I've had "fakes" come across my bench in the shop.
Repairing a customer's unit, and not knowing I was installing a fake, then later, the customer brings it back - arguing that "my" work was faulty.
I then have to RE-repair it for free.....!

It hurts my reputation as a servicer, as well as annoying the customer.
I then argue with my parts distributor, who I've dealt with for years, about their stock supply.


This fake stuff effects us all.
 
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I was very lucky to have met a great parts supplier soon after I opened my service shop. He bought from Japan directly in a group of three vendors. His parts were slightly more expensive than others, but for the reasons wiseoldtech mentioned, it was cheap insurance.

Once that supplier asked why I never complained about the higher prices (I had been dealing with him for over 10 years by then). It was very simple to state the obvious fact that I didn't have to do repair jobs twice, but also I used a standard markup (40% discount off list), so a slightly higher cost for parts didn't really affect me except for the slightly higher cost of parts in inventory.

When I worked at a parts jobber doing repairs, I had to use ECG (Sylvania) parts. They were so bad that I would poke the leads through the plastic and test them first. My return rate dropped. Then I did my own cross references (not using the ECG book) using original data books. My return rate dropped to near zero. I call the ECG and other replacement brand cross reference books, "the book of lies".

There are even people today that will use the NTE cross reference book improperly. They look up the part they need, then they will look up other parts that cross to the same NTE number and use that. You can't do that!!

-Chris
 
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Hi audiohed,
To answer your question, you are assuming the same quality in the process. That is the first thing that isn't true. Silicon slices are bought and sold in the semiconductor industry. These are how transistors and ICs start out. They are of varying purity and consistency. If your name is On Semi, you probably have your own foundry with tight controls on manufacturing. This ensures a high yield as semiconductor slices (whatever they call them) are expensive. So you must have a high yield in order to keep costs down. Whatever the semiconductor is to be, transistor or IC, they are processed photographically. Today the process is similar, but they use radiation that isn't light to make the fine features we have today. Those finer features increase consistency which is one reason that today's parts are more consistent. The exposed part either blocks or allows through the gas used to dope the silicone, or to create an insulator, or etch away some material.. The parts are built up by using different masks in order to build the vertical structure we use most often. I'm not 100% on these details, but it is basically correct.

Now, if you want to make a lot of money, what do you do? You slash costs by buying cheap wafers (that's what they are called!). Also, lower resolution masks and less pure processes with looser control over exposure times. Then they encapsulate their nice fresh junk and mark the case as something it isn't. If they are really rotten, they will put a smaller die (the actual transistor) in that big case. Smaller die = lower power part. Inside most power transistor packages there is an intermediate mounting surface for the die called a heat spreader (guess what it does ...). They omit this part that normally exists in a power package causing the part to be even less able to withstand much power dissipation.

Of course, there is the time honored practice of buying low power parts cheap, cleaning the original markings off and placing whatever part it is you want to sell.

I have even found fake 2N3904 /2N3906 transistors! One of the most common, least expensive transistors out there. I can't understand that business plan, but it obviously works from some creeps selling fakes.

There is only one defense against getting fake transistors you have possible. Buy only from authorized distributors. We even had some fakes in that channel. People would buy real parts, and return them, except they were the fake parts. That is one reason why it is more difficult to return parts. Even if they accept the parts back, if there is any doubt, they destroy the returned parts immediately.

Fake parts is a very serious problem in the world today. It affects every industry including automotive, aviation and even the space program. Let's not mention the medical devices industry.

Anyway, that is why you have fakes. They do not manufacture on an even playing field.

-Chris
 
I don’t think I would ever trust the NTE listings for ICs, they list WAY too many parts as viable substitutes to be possible in all applications. If they’d just list what the parts actually are, you might have better luck.
There is only one NTE part that I use, and it’s a philips, soft recovery power diode for preamps and DACs...
 
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I don’t think I would ever trust the NTE listings for ICs, they list WAY too many parts as viable substitutes to be possible in all applications. If they’d just list what the parts actually are, you might have better luck.
There is only one NTE part that I use, and it’s a philips, soft recovery power diode for preamps and DACs...


I've heard from others online on several sites that they don't like NTE/ECG.
Yet, in the past 30 years of using them in servicing audio/video, I've never once had an issue.
 
before it was NTE it used to be ECG /Phillips and in those days the cross reference data was somewhat better vetted by users/industry but was still plagued by parameter spread of devices sourced or re/produced under license for the replacement market so was not the best device for "replacement" in designs that required specific performance parameters.
there's still a large divide between number of units produced "that make the spec" and market demand that it's no wonder fakes are lucrative especially with RHOS regulations preventing any attempts at new production on older types from coming to fruition.
 
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