hello and thank you,
yes that was one of the first pages i came across while reading up on this. He has a lot of great information on that site.
I am still curious as to whether or not Toshiba ever actually made transistors that look exactly like these ones with the shiney surface area, or whether anyone has identified another manufacturer who's packages are being branded as Toshiba.
Was there ever a batch of genuine Toshibas with this shiney area and very clear lettering on the package?
yes that was one of the first pages i came across while reading up on this. He has a lot of great information on that site.
I am still curious as to whether or not Toshiba ever actually made transistors that look exactly like these ones with the shiney surface area, or whether anyone has identified another manufacturer who's packages are being branded as Toshiba.
Was there ever a batch of genuine Toshibas with this shiney area and very clear lettering on the package?
Hi,
my Tosh 1943/5200 have a plain matt surface and the printing is very difficult to read.
Are they laser etched?
The backs of mine look nothing like those pics.
Mine have mickey mouse type ears at the top due to the top line having a depressed edge and the sides have an indent.
The bottom edge is completely straight.
my Tosh 1943/5200 have a plain matt surface and the printing is very difficult to read.
Are they laser etched?
The backs of mine look nothing like those pics.
Mine have mickey mouse type ears at the top due to the top line having a depressed edge and the sides have an indent.
The bottom edge is completely straight.
I have a bunch of TIP42 they all measure hfe between 130 and 220 most over 200.... datasheet says it should be 15-75...
ARE THEY FAKE?
My toshiba sc5200s are pretty clearly labled..lazer etched fairchild 1943 has harder to read lettering - faint ink?
ARE THEY FAKE?
My toshiba sc5200s are pretty clearly labled..lazer etched fairchild 1943 has harder to read lettering - faint ink?
At the beginning of this thread is photo of genuine Toshibas...
http://www.diyaudio.com/forums/attachment.php?s=&postid=954973&stamp=1152129483
Compare yourself!
Mike
http://www.diyaudio.com/forums/attachment.php?s=&postid=954973&stamp=1152129483
Compare yourself!
Mike
No, No, I believe you, just thought they may have changed since...
a ny clue on those tip42's of mine with the huge hFE?
a ny clue on those tip42's of mine with the huge hFE?
Very suspicious. I have some TIP41's and 42's purchased years ago and their hFE is around 40 which is what I'd come to expect. The hFE you describe sounds like that of a small signal transistor glued into a bigger case.
could I use some resistors and set it up like a switch with a 40v 5A load (Ic), to see if it can handle that kind of duty in class ab... or can one not compare the 2 modes of operation...
If you have it on a heatsink that exceeds the thermal capacity of the transistor, then there's no reason you can't go towards Icmax in a class A config. If it's gonna die, that'll do it, just bias it up and crank the Vcc up watching the current.
I'm betting they'll go with an Icmax under 1A
I'm betting they'll go with an Icmax under 1A
thanks will heat my hands over them in the morning.... 😱 
Just thought of it, it is just a driver, so it will probably just see about 5 to 10W max....
Just thought of it, it is just a driver, so it will probably just see about 5 to 10W max....
I have a couple of MPSA42's here of which I suspect contains fakes. I just finished a project which wouldn't work, which was caused because one of the transistors didn't work. And because the ones I bought today look significantly different than ones I had used before, I suspect they may be fake.
I have four versions:
The first one is the one I got today (the suspected fake), which has a silver front, which the other three don't have.
Also, the first one is the only one I have which has it's legs bent sideways like that. The datasheet shows an image where they are straight. However, if that would be an indicator, all of the counterparts to this one I have (the MPSA92), would be fake...
I don't understand why the second one is labeled KSP42 BTW, but that's what I got when ordering MPSA42's...
Could I be dealing with a fake one, or multiple fakes, here?
I have four versions:
The first one is the one I got today (the suspected fake), which has a silver front, which the other three don't have.
Also, the first one is the only one I have which has it's legs bent sideways like that. The datasheet shows an image where they are straight. However, if that would be an indicator, all of the counterparts to this one I have (the MPSA92), would be fake...
I don't understand why the second one is labeled KSP42 BTW, but that's what I got when ordering MPSA42's...
Could I be dealing with a fake one, or multiple fakes, here?
HelemaalGaar,
the first one is original Philips manufacture, including the grey flavor.
There are at least as many different MPSA manufacturers as fingers on your hand.
the first one is original Philips manufacture, including the grey flavor.
There are at least as many different MPSA manufacturers as fingers on your hand.
Couldn't resist, could you 🙂
I believe I have ruled out mistakes in the circuit, so I hope it was a normal DOA then. The transistors are part of a DC protector in a subwoofer, and I wouldn't want that to fail on me...
MY BDW94C
(left original ST)
(left original ST)
An externally hosted image should be here but it was not working when we last tested it.
