My Transistors, original or copy?

[Bassivus]

Interesting. Datasheet only specifies full length pins.
But usually they can be ordered bent/cut according to customer needs. So it would be a custom ordered batch then.
But then the date code, it is not mentioned in the datasheet, but Fairchild/On-semi should be YWW, and also somewhere it says that Y is last digit of year. In that case J is not a valid year
Also the date code is very far to the right side...almost too close to edge. Again, not sure about any specification on location.

Anyway I did not find any detailed info on this so maybe someone else is wiser?

@jlithen Thank you, I could not find that YWW info on the web...

I've never come across cropped leads either but I would say that companies like Nikko probably buy up unused and perhaps custom parts and so it may well be OK.

It might be interesting to give one a rub with a solvent and see if any other markings appear underneath.

@Mooly I was thinking the same on the cropped leads... When I ordered, the first package didn't arrive 3 weeks... probably COVID mess. They sent a new pair that I got in a week. After 5 weeks I got the first envelope also, so now I have a spare that I can crack open to see the wafer.
It would help to know if Nikko is to be trusted but I'm rationalizing that no company in the UK would survive 40 yrs selling fakes...

 

[kees52]

I have recently bought Fairchild KSE340/350 from Nikko Electronics UK. I have been warned those look fake. Those 340s came short leged but under a magnifier, they look like factory cut. There is zink on the bottom. Has anyone seen such cut legs from factory?!?!
Any opinions, perhaps measurements that would help to compare?

If the parts have clean nice and new looking pins, then possible fake, short pins can mean she get them from boards and resell, maybe then these are real

I did say before we need to have suppliers who are trustable and set them here, nut most of them get parts from others and do not even now she are fakes because of lack of electronic knowledge.

 

[JeffYoung]

Nikko sold me counterfeit 2SK2013s and 2SJ313s. To their credit, they were good about taking them back when I informed them....

I'd measure the devices at 6 to 10 points on the Id/Vgs curve and see if they match the datasheet. (My "2SK2013"s were waaay off.)

 

[Bassivus]

Here are the pics:
KSE340

1. Measurement
2. Front
3. Back
4. Inside (halo from magnifier glass)

 

[kees52]

Vojvodina? been there in past, our cook did live there, I have friends in belgrade.
Have working in a serbian restaurant, in 1983, long ago, cooking with the chef who is unfortune not longer with us...

These transistors looks bad for me, but I do not now.

It is a shame china does nothing about it.

regards

 

[Bassivus]

@kees52
Greetings from Novi Sad
On those trannys. It was sourced from UK shop...

 

[kees52]

UK shop?? and false that is not good.

Novi Sad is the light city like Eindhoven in the Netherlands was, until Phillips did move away sadly nothing is left.

 

[ti5002000]

Toshiba 2sa1145

Hi guys

I tested some 2sa1145 in mu dac pro curve tracer .
Happens that in the IC/VCE graph comparing to the datasheet at IB= 100uA (0.1 ma) the curve stops at VCE= 1 v .

images in attachment

Does this means they are fake or i am missing something?

this is the first time i use a curve tracer.

Thanks in advance

 

[Trollet]

You reach max current on the tester.
If you press autoset it will adjust base current down to working conditions.

/Figge

 

[ti5002000]

If i put autoset , the max IB current is 90ua and at that the VCE is 1v

i only can get the transistor to reach the vce = 10v like the datasheet at IB= 20ua

Does this means it is still is in the original specs or could be fake?

Thanks for the help

 

[motul]

Just got these in but I am returning them since I purchased On semi equipments. I don’t want to take a chance

 

[wg_ski]

You know those have been in production in almost 30 years. They disappeared when the C3281 was still in widespread use. I doubt there are that many real ones left in stock on the planet. Those don’t look anything like any Toshiba device ever produced. I bet they don’t have the “figure 8” coin insert in the bottom side, either.

The only real ones you will find nowadays are pulls - and you’ll have a problem getting them out of the owner/hoarder’s cold dead hands except to repair a vintage amp which had them originally. For sale anywhere? Probably not for less than $100 apiece.

If building a new amp, just use MJ15024 or MJ21194.

 

[N101N]

An unduly optimistic expectation...

 

[K-amps]

What do u guys think? real or fake? Came out of a kit so i am 50/50 on this.
ON njw0302

The wafer is about 6.3mm, seems to be about the right size..

 

[Mooly]

Just got these in but I am returning them since I purchased On semi equipments. I don’t want to take a chance

They do look a bit suspect, not just the lettering but the metalwork itself. I know pictures can be deceiving but these look to have burrs all around them.

 

[motul]

I returned them. The seller was very understanding. On Semiconductors are on the way! 10 to be exact.

 

[Mooly]

sounds a like a good result tbh.

 

[wg_ski]

What do u guys think? real or fake? Came out of a kit so i am 50/50 on this.
ON njw0302

The wafer is about 6.3mm, seems to be about the right size..

That one looks real enough to me. It is the right size die, and they are using a copper lead frame (and a very thick solder die attach). There is something else wrong with your amplifier, you just have t found it yet.

 

[kozard]

Please give me your opinion (real or fake) for the two TIP35C shown in the pictures on the left. The four other devices (middle and right) were purchased from Mouser (authorized distributor).


I have included capacitance measurements and the voltage drop when configured as a base-collector connected diode. Perhaps not the best test but I had the equipment for it and I thought 25A TIP35C should handle 8-9A and 1-2V for a few seconds.


The grey (left) volt meter is measuring the current (the voltage drop over the 1 Ohm series resistor.)


The red (right) volt meter is measuring the voltage across the base-collector connected diode. (Voltage from BC to E.)

 

[kees52]

They do look a bit suspect, not just the lettering but the metalwork itself. I know pictures can be deceiving but these look to have burrs all around them.

Right! really fake, bad made.