Hello Folks,
Talking about fake transistors, has anyone tried UTSource?
I’m finding mixed reviews on the net, they say they have some old Toshibas I’m looking for and they’re selling them as NOS and directly from them rather than 3rd Party Sellers, so they guarantee they are 100% original.
Also they accept PayPal so if they end up being fake that’s an additional level of protection.
Thanks!!
Talking about fake transistors, has anyone tried UTSource?
I’m finding mixed reviews on the net, they say they have some old Toshibas I’m looking for and they’re selling them as NOS and directly from them rather than 3rd Party Sellers, so they guarantee they are 100% original.
Also they accept PayPal so if they end up being fake that’s an additional level of protection.
Thanks!!
Search for UTsource on this forum.
Some have had good results and some have had FAKES.
Utsource for components ?
Andy
Some have had good results and some have had FAKES.
Utsource for components ?
Andy
Repairing Thule Audio Spirit IA60B amp. Bought 2SA1633 by Rohm (as original) but receive PMC. According alldatasheet.com only New Jersey Semi-Conductor Products Inc. uses TO-3PN for this transistors. All another use TO-247. And no information about PMC. What is it? Another one chinese manufacturer and I can use this transistor?
I measured Hfe=94 (datasheet corresponds 100-200 for 2SA1633E and original pair 2SA1633E/2SC4278E has hfe 147/148).
Photo
I measured Hfe=94 (datasheet corresponds 100-200 for 2SA1633E and original pair 2SA1633E/2SC4278E has hfe 147/148).
Photo
I ended up ordering some Power Transistors from UTSource, they all were available with the New and Original guarantee, I have weighted, measured, curve traced them and compared to originals and even tried erasing the labels and everything seems fine to me, any visual red flags for you folks?
Those packages look like many that I have received from Ebay and Aliexpress with just about any brand and part number you want on them. They have always turned out to have much lower current and SOA than they should. I concluded that they were all fakes with much smaller die inside. I don't buy them anymore. After the first few failures I started making test circuits/jigs. Pretty soon it was obvious that every one was a fake regardless of the part number or seller. Many of the sellers appear to be the same person or group with many accounts of different names.
For repairs I try to find some sort of currently available Sanken or Toshiba that will work and order from Digikey or Mouser.
If you are talking about the one on the left hand of the second picture, that’s an International Rectifier not Toshiba, its an IRFP044 and yes that’s the only thing I noticed, more like rust than mold and only this one came like that.
Interesting. Please ask on your delivery source (ordering address), from where they in turn bought the ROHM copies.
For this ROHM transistors I use as replacement parts such from SANKEN (2SA1294/2SC3263, order on Profusion). Your image I have upload here, because on imgur.com the image was delete someday.
Under "PMC" I have found this:
PMC-Sierra - Wikipedia
but I don't think, that is the company makes the ROHM copies.
Check out also this URL:
bipolar (bjt) transistor families for audio power output stages
Attachments
Last edited:
If you look at the edge of the tab is it a copper/copper alloy color? Genuine is a copper color as shown in the attached pictures of genuine Toshiba 2SC5242 and 2SA1962 in one of my defunct Onkyo receivers. To the best of my knowledge your 2SA1986 should externally look like 2SA1962 if they are genuine.
Unfortunately I can not get a better picture since they are still inside an assembled amplifier.
Attachments
The copper based lead frame is a good sign. I guess it is possible then that they might be genuine. But they must be quite old stock given the marking technology compared with modern Toshiba manufacture. I am very suspicious when I see very old Toshiba stock with full length leads. Toshiba power transistors are very commonly faked. Especially the ones that are long out of manufacture.
One other check you could do is at Vce = 5V you could measure the hFE at the current specified on the Toshiba datasheet and see if that matches the hFE rank printed on the parts. One is printed "O" and the other "R". Fakes often do not match the marked hFE rank.
I would be careful otherwise with fakes you can blow the new outputs, the drivers, etc.
One other check you could do is at Vce = 5V you could measure the hFE at the current specified on the Toshiba datasheet and see if that matches the hFE rank printed on the parts. One is printed "O" and the other "R". Fakes often do not match the marked hFE rank.
I would be careful otherwise with fakes you can blow the new outputs, the drivers, etc.
Last edited:
Oh well that was a good test, so I measured 3 each and the results aren’t quite accurate.
C5358 - O are supposed to be 80 to 160 Hfe and I got 60, 61 and 63.
A1986 - R are supposed to be 55 to 110 Hfe and I got 52, 58 and 70.
If you measured them at the datasheet Vce and current then I would be concerned, especially the O rank. Note that the very useful M328 tester is not really suitable for testing power transistors because the test conditions are far from the datasheet test conditions. (I mention that just in case you used that.)
The genuine Toshiba and Sanken that I have bought from Mouser, Digikey and LCSC always have good gain. For 2SC5200N I consistently get 100 to 110, for example. Never seen one at or below the minimum specification.
The genuine Toshiba and Sanken that I have bought from Mouser, Digikey and LCSC always have good gain. For 2SC5200N I consistently get 100 to 110, for example. Never seen one at or below the minimum specification.
I have not used one of those but 1 Amp and Vce = 5 volts should give you a result close to the datasheet.
I have stopped buying power transistors from sources like Ebay and Aliexpress. My recommendation is to cross to a suitable currently available device and try that. (Being prepared to measure and set bias, etc.)
I am not familiar with your amplifier so I can't say whether or not you could use the Toshiba 2SC5200N and complement (available at Mouser). Or the Sanken 2SC6145 and complement (available at Digikey.) Perhaps someone else can comment. I suspect that something like the Toshiba 2SC5200N or 2SC5242OTU will turn out to be "closely related" in design and specifications.
That would be my suggestion: Investigate a suitable currently manufactured replacement purchased from an authorized distributor like Digikey or Mouser.
I have stopped buying power transistors from sources like Ebay and Aliexpress. My recommendation is to cross to a suitable currently available device and try that. (Being prepared to measure and set bias, etc.)
I am not familiar with your amplifier so I can't say whether or not you could use the Toshiba 2SC5200N and complement (available at Mouser). Or the Sanken 2SC6145 and complement (available at Digikey.) Perhaps someone else can comment. I suspect that something like the Toshiba 2SC5200N or 2SC5242OTU will turn out to be "closely related" in design and specifications.
That would be my suggestion: Investigate a suitable currently manufactured replacement purchased from an authorized distributor like Digikey or Mouser.
.
These are currently on offer on Fleabay.
Anyone spot the error ??
ARE THEY GENUINE ?
.Matched Quad 405 Replacement 2n3773 Transistors,best quality ever | eBay
Andy
These are currently on offer on Fleabay.
Anyone spot the error ??
ARE THEY GENUINE ?
.Matched Quad 405 Replacement 2n3773 Transistors,best quality ever | eBay
Andy
