How much profit could there be
in counterfeiting six-cent MPSA56's? It better be a lot, because I spent the last three moths chasing phantom oscillations that were caused by bad MPSA56's. They were marked
CE
MPS
A56
and every single one measures "weird" and causes the amp to act strange. It was just being used as the current limiter on the VAS - literally any good transistor would have worked. Hfe about 400 with a VBE around a quarter of a volt (but they do work as a PNP transistor).
in counterfeiting six-cent MPSA56's? It better be a lot, because I spent the last three moths chasing phantom oscillations that were caused by bad MPSA56's. They were marked
CE
MPS
A56
and every single one measures "weird" and causes the amp to act strange. It was just being used as the current limiter on the VAS - literally any good transistor would have worked. Hfe about 400 with a VBE around a quarter of a volt (but they do work as a PNP transistor).
I have fake Toshiba 2sc3423s with laser-etched Toshiba logos, in a package which turns out to be inaccurate(isolated TO-126ML instead of 2-8H1A) - they turned out to be PNP devices with hFE ~= 360. Are they wrongly-marked 2sa1360s, or a small-signal dies like bf423/mpsa92/bc558 packaged into isolated TO-126 packages? Probably the latter, maybe even the same die as the fake MPSA56 above.
I'll try to break one open in due course and take a look.
I'll try to break one open in due course and take a look.
Hi,
2N3773 "Toshiba"
I had fortunately only one of it
http://www.diyaudio.com/forums/showthread.php?s=&postid=1465732#post1465732
But I have a Lot of These...
everything makes me suspect that it is a fake.
which factory does it have this logo ?
Now I do remove the Glue....
2N3773 "Toshiba"
I had fortunately only one of it
http://www.diyaudio.com/forums/showthread.php?s=&postid=1465732#post1465732
But I have a Lot of These...
everything makes me suspect that it is a fake.
which factory does it have this logo ?
An externally hosted image should be here but it was not working when we last tested it.
Now I do remove the Glue....
this makes me believe that it is a fake:
- absence of copper pad
- chip of the same sketch of the "red label" Toshiba
Also for remove the withe silicon :
- 24 hours of soak in (premium) gasoline to soften the glue
- steel brush to remove residues
- washing and cleaning with toothpaste
(the only disadvantage is that they detach him the threads)
Fake or True ?
every suggestion is very appreciated...
bye
- absence of copper pad
- chip of the same sketch of the "red label" Toshiba
Also for remove the withe silicon :
- 24 hours of soak in (premium) gasoline to soften the glue
- steel brush to remove residues
- washing and cleaning with toothpaste
(the only disadvantage is that they detach him the threads)
Fake or True ?
every suggestion is very appreciated...
bye
Gold_xyz said:
Neither!
As it does not claim to be an original OnSemi/Motorola it can't be fake. But it is also not an original, just manufactured by someone else.
It is obviously not the quality of an original, but not necessarily useless.
I don't remember the logo, but being a real manufacturer, he will not produce useless parts.
I believe you can use these parts.
Mike
Gold_xyz said:
Which it likely is, just not an original.
That yours is Chinese manufacture does not necessarily make it inferior, the slow mode 2n3055 and it's sturdier versions are produced by a whole bunch of semi companies.
Toshiba China likely manufactures semis like these, stuff that Toshiba Japan has no appetite for producing anymore.
The same applies to several higher grade semi numbers which Toshiba licensed to Korean facilities, manufactured there nowadays but not anymore in Japan.
Securing the die and connections with a dab of silicon does not immediately label it a fake, merely a different manufacturing approach.
Had it been labelled a 15003 or a 15024, then it would have been a counterfeit device.
!
Does anybody know who is manufacture of this transistors?
Does anybody know who is manufacture of this transistors?
An externally hosted image should be here but it was not working when we last tested it.
