This is what I have for 2SA1302 and 2SC3281. Unfortunately, I returned the fakes back before I could take any photos of them, or smash at least. I also don't have any original smashed 2SA1302 and 2SC3281.
Notice the way those letters appear:
O, B and A in TOSHIBA.
A, 0 and R in 2SA1302.
8 and R in 2SC3281.
A and P in JAPAN, both of them.
An externally hosted image should be here but it was not working when we last tested it.
Notice the way those letters appear:
O, B and A in TOSHIBA.
A, 0 and R in 2SA1302.
8 and R in 2SC3281.
A and P in JAPAN, both of them.
Last edited:
Left: 7812, Right 7912
Wondering whether the 7812 can handle +35V input voltage as specified
Wondering whether the 7812 can handle +35V input voltage as specified
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
The 78 range of regulators are specified up to 28volts input, NOT 35!
Motorola used to fill their 2N3055 transistors with silicon heat paste, Texas Instruments didn't. That doesn't make the TI transistors fake.
Motorola used to fill their 2N3055 transistors with silicon heat paste, Texas Instruments didn't. That doesn't make the TI transistors fake.
Fairchild and ONsemi both specify their 78xx @ 35V as max Vin. Both state 40V for the 7824 version.
If it looks like a duck and quacks like a duck....
Does it have silicone on the die ? Fake.
Does it completely fail to match the performance of the "first source" part ? Fake.
Cobra2, you cannot double-die transistors like that. So it's an inferior product.
Don't make excuses for China's lack of respect for intellectual property rights.
Does it have silicone on the die ? Fake.
Does it completely fail to match the performance of the "first source" part ? Fake.
Cobra2, you cannot double-die transistors like that. So it's an inferior product.
Don't make excuses for China's lack of respect for intellectual property rights.
"you cannot double-die transistors like that"
ON Semiconductor used to make a 400W double-die version of the MJ21196 part, don't know what it looked like inside.
ON Semiconductor used to make a 400W double-die version of the MJ21196 part, don't know what it looked like inside.
I learned my lesson quite early on in electronics and always buy from reputable dealers like RS Components and Farnell.
Quite often they are more expensive on ebay than the two companies I mention.
RS even does free delivery.
Quite often they are more expensive on ebay than the two companies I mention.
RS even does free delivery.
You need to put some effort in and find equivalents.
RS and Farnell are good for searching for a transistor type and spec.
Last edited:
Yeah, you can find "equivalents" - if you are willing to retrofit an old unit to accept plastic packages. Current production parts will replace 99% of what's out there, except for TO-3's. For those you're pretty much limited to 4 MHz parts. Many times (more often than not) an amp is perfectly happy with them. Worth a try, when the alternatives are either hack it, trash it, or roll the bones with fakes.
I do not consider them fakes, as they engrave their company-name on them.
BTW, who makes the "real" LM317 ? And you religious use only this brand?
Arne K
BTW, who makes the "real" LM317 ? And you religious use only this brand?
Arne K
Arne K, The problem is that fakes engrave the real company name on them. That's the whole problem with fakes, especially as companies have changed their production techniques and labelling methods over the years. The only way to identify some fakes is test to the point of destruction!
Toshiba
mine are bought any years back here schuro shop.
- they have glossy backplate
- toshiba is same print in thick of lines like 1943/5200
- only the O than one point above and only 3 number code
(not extra letter+2numbers)
- at last JAPAN
this one not sure real ones.
With IRFP is a great dilemma newer days- you can buy this one you have-
also here reichelt, digikey has newer- not tinned legs.
I have bought IRFP 250-M Mouser older I- heart- O-R types- silky legs- good
ones- in Circlotron and ACA.
But it's a Challange!
In TME i became IOR(heart) 9140- now needed some 240.
mine are bought any years back here schuro shop.
- they have glossy backplate
- toshiba is same print in thick of lines like 1943/5200
- only the O than one point above and only 3 number code
(not extra letter+2numbers)
- at last JAPAN
this one not sure real ones.
With IRFP is a great dilemma newer days- you can buy this one you have-
also here reichelt, digikey has newer- not tinned legs.
I have bought IRFP 250-M Mouser older I- heart- O-R types- silky legs- good
ones- in Circlotron and ACA.
But it's a Challange!
In TME i became IOR(heart) 9140- now needed some 240.
Tayda generally sells good stuff. Only way to know for sure is take it to a vise and crack it open. Real Toshibas have a big square silicon die perfectly centered on tab. Fakes have a small die crooked mounted and covered with white silicone RTV.
You can also measure capacitance of base to collector. A small die has small capacitance relative to real one which is larger.
some NEWS about Toshiba
Hi maouna and interested.
send pics from my last bought 2SC5200 O Toshiba from digikey, 14 days back.
That is TO-3P new production since 2015- you can reed on PDF there.
What is happen with your Trannis? 😱
The Fakers ??? have taken the new LOGO ? or production has changed
to new LOGO with old TO264 Typ- is this possible? 😉 😕
You can compare- the older working in onkle Charly DX-Amp and the news
should in a Ranchu/AKSA Quasi Amp.
Hi maouna and interested.
send pics from my last bought 2SC5200 O Toshiba from digikey, 14 days back.
That is TO-3P new production since 2015- you can reed on PDF there.
What is happen with your Trannis? 😱
The Fakers ??? have taken the new LOGO ? or production has changed
to new LOGO with old TO264 Typ- is this possible? 😉 😕
You can compare- the older working in onkle Charly DX-Amp and the news
should in a Ranchu/AKSA Quasi Amp.
