counterfeit output transistors
- Thread starter spacelord
- Start date
spacelord
Great Googly Moogly
EchoWars said:
hey Glenn,
Sorry for the slow responses, it was my weekend to work, 12 hour shifts.
About the 2sc116a transistor.
Cd fixer gave me the following parameters: Fluke Dmm Diode test position, readings should be Base to collector .440-.550 / Base to emitter .440-.550
I got the following: base to collector .557 / base to emitter .559
I was unsure of how close it was necessary to stay within the specs I received from cdfixer, so I just ordered an extra output in case this one was no good.
What is your opinion, Glenn ????
In case cdfixer sees this, how is my driver board going Jim???
Chris
4.7inches
Active Member
Bringing this subject up again from the dead since I have a related problem/issue.
I need semiconductors to my broken au-20000 and found the suitable replacements. Seller claims they are from former dutch Sansui distributor. He has a lot of other stuff(replacement knobs etc) which in my eyes makes his claims more trustworthy. He obviously has bought a stock from Sansui distributor. I have pictures of them and they seem real to me although there are minor differences from the ones shown earlier in this thread. Maybe the amount of ink can differ from one batch to another?
Attached pictures all show his Sankens.
I need semiconductors to my broken au-20000 and found the suitable replacements. Seller claims they are from former dutch Sansui distributor. He has a lot of other stuff(replacement knobs etc) which in my eyes makes his claims more trustworthy. He obviously has bought a stock from Sansui distributor. I have pictures of them and they seem real to me although there are minor differences from the ones shown earlier in this thread. Maybe the amount of ink can differ from one batch to another?
Attached pictures all show his Sankens.
Attachments
Top looks rounded and they seem to be missing the matte finish...they just don't look right.
Yes', Ive heard about this Dutch guy too, but 'once bitten, twice shy'. The new On-Semi transistors work fine and don't cause me to do the troubleshooting thing twice...the second time when the fakes blow up.
Yes', Ive heard about this Dutch guy too, but 'once bitten, twice shy'. The new On-Semi transistors work fine and don't cause me to do the troubleshooting thing twice...the second time when the fakes blow up.
4.7inches
Active Member
Is there any way of finding out which one´s fake when you have one at hand? Why not then order one and test it?
My technician who has more than 30 years experience of Sansui actually thinks these look more real than some of the items mentioned earlier as "the good ones". This seem to be a very tough area indeed.
The reason I am looking for Sanken instead of On-semi is that the originals are so much better from what I´ve heard.
My technician who has more than 30 years experience of Sansui actually thinks these look more real than some of the items mentioned earlier as "the good ones". This seem to be a very tough area indeed.
The reason I am looking for Sanken instead of On-semi is that the originals are so much better from what I´ve heard.
The only reliable testing destroys or damages the device. Better to buy devices where the pedigree is without question.
Better in what way? In most amplifier designs (and this includes the AU-20000), the choice of output transistor has pretty much zero effect on the resulting sound quality.
I simply refuse to roll the dice anymore. I buy what I know will work, and move on to the next project. I would not be able to either hear the difference between the Sanken devices and the On-Semi's, or measure it with test gear (although the low saturation voltage of the On-Semi transistors often means that you might pick up a few extra watts of power at the output). And it beats the hell out of having to pull it all apart again because the transistors you chose turned out to be ****.
rabbit
Well-Known Member
The only problem is that there are plenty of counterfeit OnSemi devices so you have to be careful of these too
Two good websites on identifying counterfeit transistors
http://sound.westhost.com/counterfeit.htm
http://www.geocities.com/cdkands/counterfeits.html
Nicowico
Active Member
I see, you don't trust me. The pictures are mine so are the transistors.
About the matte finish. I depends how you take the photo, same for the round shape.
OK, the printing? When your amp was built 30 years ago they used new transistors and when you blow the transistors after 30 years the transistors still looks like new because nothing happened to them. My transistors are NOS so they are 30 years old, but they were not sitting in an amp, no they were laying in a drawer or a box so after 30 years the printing becomes dammaged.
Your technician bought also some transistors from me and he claimed that they were fakes, but he tested them and they were not Ask him.
I have sold a few to a Audio Karma member at the time there was a dispute here again about counterfeits. Unfortunately he did not react, but I guess if I have sold him fakes, he would do.
Not important at all, but look at my Ebay feedback. I have sold a lot of Sansui stuff always "fast shipping, wel packed and no fakes."
Anyway the transistors are shipped to you. I hope you let the people here know if they are fakes or not. I'm glad to here it from you or anybody else.:yes:
Attachments
240sx4u
Lunatic Member
Why should he trust you? People sell fake devices all the time. He has every right to post up asking if the devices "look real".
Looks like he went ahead and ordered them, not sure why your so bent out of shape here.
Evan
4.7inches
Active Member
Sorry, I do not understand your reaction, I did not call you out as a fraud or anything - just wanted a 2nd opinion.
Nicowico
Active Member
OK, no hard feelings. It's more to Echowars "Top looks rounded and they seem to be missing the matte finish...they just don't look right."
I AM a reputable seller and I stand for what I sell!!!
I'm hurt.
Sorry if you don't understand my skepticism. It isn't a personal slight on you, but a general avoidance of parts coming from an unknown and unproven source. Until I have a set in my hot little hands and install them in an amp, then do my damndest to blow them up (and fail to do so), I shall remain a skeptic. I've paid the members fee to be one of the 'NOS Japanese Rare Output Transistor Skeptic Club' ($1K or so in worthless 'not-fit-for-a-landfill' fakes through the years), and am in good stead with this group.
You may have the real thing. But then again, that's what they all say. Sorry if that upsets you. Please don't take it personally. The longer you are around here, and the more people get to know you (and perhaps a few buying and using some of your power devices with success), then the trust level may build.
Sorry if you don't understand my skepticism. It isn't a personal slight on you, but a general avoidance of parts coming from an unknown and unproven source. Until I have a set in my hot little hands and install them in an amp, then do my damndest to blow them up (and fail to do so), I shall remain a skeptic. I've paid the members fee to be one of the 'NOS Japanese Rare Output Transistor Skeptic Club' ($1K or so in worthless 'not-fit-for-a-landfill' fakes through the years), and am in good stead with this group.
You may have the real thing. But then again, that's what they all say. Sorry if that upsets you. Please don't take it personally. The longer you are around here, and the more people get to know you (and perhaps a few buying and using some of your power devices with success), then the trust level may build.
240sx4u
Lunatic Member
What I meant by "bent out of shape" was that you seemed irritated and annoyed that he would post questioning your parts.
Seems that may not be the case, I apologize if I seemed harsh.
Evan
naderpe
Well-Known Member
Marker permanency test
A mixture of 3 parts mineral spirits and 1 part alcohol is used for testing for a re-marked component.
Mil-std-883 (method 2015.13) requires markings to withstand a swab wash without fading. The manufacturers are very proud of their products and use the right procedure and paint to make markings permanent, the counterfeiter is less sophisticated in the marking process. They can get the correct paint but do not bake or apply it well enough to withstand the test, (at least for now anyway).
Genuine Toshiba passed the marking permanency test while the other two had the red marking rub off.
The first picture is of a genuine 2SD424, second of a counterfeit 2SD424 example 1 that looks good but was missing the silicon over the die. I haven’t installed one to see if it works but I think it will. Counterfeit #2 if you can see through my crude scratches is very dissimilar from the original.
The last picture, counterfeit example #2 is at 50x while the first two pictures are at 25x.
Peter
A mixture of 3 parts mineral spirits and 1 part alcohol is used for testing for a re-marked component.
Mil-std-883 (method 2015.13) requires markings to withstand a swab wash without fading. The manufacturers are very proud of their products and use the right procedure and paint to make markings permanent, the counterfeiter is less sophisticated in the marking process. They can get the correct paint but do not bake or apply it well enough to withstand the test, (at least for now anyway).
Genuine Toshiba passed the marking permanency test while the other two had the red marking rub off.
The first picture is of a genuine 2SD424, second of a counterfeit 2SD424 example 1 that looks good but was missing the silicon over the die. I haven’t installed one to see if it works but I think it will. Counterfeit #2 if you can see through my crude scratches is very dissimilar from the original.
The last picture, counterfeit example #2 is at 50x while the first two pictures are at 25x.
Peter
