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Old 8th February 2013, 02:45 PM   #491
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Quote:
Originally Posted by Leakstereo20 View Post
where ?
If they're difficult to get in Denmark, order direct from Profusion in the UK.

(the Sankens, and all other Japanese semi-parts, have been available here for 3 decades. A couple of years more than I have bought them, so it comes free. The DIY experience I have in general will likely scare you)
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Old 8th February 2013, 03:12 PM   #492
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Quote:
Originally Posted by jacco vermeulen View Post
If they're difficult to get in Denmark, order direct from Profusion in the UK.

(the Sankens, and all other Japanese semi-parts, have been available here for 3 decades. A couple of years more than I have bought them, so it comes free. The DIY experience I have in general will likely scare you)
Thanks for the UK link...I am not that easy to scare

I am sure that you got experience. The supplier I bought the Toshiba's from promised me 10 new pcs of genuine Toshiba 2SA1943.
My experience and my measuring equipment is not enough to evaluate a difference between the Chinese and Japanese transistor types, but my genius of a buddy can do it.
I shall try to return with some measurements of the two 2SA1943 transistor types.
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Old 24th March 2013, 04:49 PM   #493
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Hey folks any way to tell if a transistor is a fake or not by picture, or has anyone purchased Toshiba 2sd845/2sb755 from ebay seller.

I was looking at these,

1pair or 2pcs Transistor Toshiba MT 200 2SB755 2SD845 B755 D845 | eBay

all so how do I want these matched, I was told I did, and didn't but if I can get them matched that would just be better regardless.

Thanks
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Old 29th March 2013, 09:10 PM   #494
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No way I know of to tell by a picture alone - especially since they may show a pic of genuine parts and ship something else.

Roll the dice...

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Old 29th March 2013, 09:31 PM   #495
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Given the source, I'd be very suspicious!
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Old 29th March 2013, 10:27 PM   #496
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@duder1982: I bought some transistors from this seller (different type). Shipment was extremely slow. Some transistors were missing due to poor packaging.
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Old 29th March 2013, 10:39 PM   #497
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There was a U.S. seller that was selling some matched pairs on the bay a while back, I wish I would have pulled the trigger for those.
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Old 2nd April 2013, 01:02 AM   #498
gman76 is offline gman76  United States
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I'd be careful of ANYTHING from China. I worked for a nonvolatile memory company, and you wouldn't believe how much counterfeiting has been going on in the last few yrs. Some assembly house in SE Asia would take either a commodity die and package that up, then sell it as a our device (of course at a premium price). Sometimes we would open up the package all to find NO DIE inside, no wire bonds, just a lead frame. These assembly houses even got our part marking to the point where we had a hard time identifying it as a counterfeit, they would copy previous date code and lot code combinations. And of course copy the logo pretty well.

The main problem is that all this junk in going thru the brokers. If you buy from a non-authorized distributor, all bets are off.
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Old 24th May 2013, 11:52 AM   #499
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this URL with various die-Images Looks interesting:
Index of /repairbasicsforbcae1/images/transistordiesx
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Old 29th May 2013, 07:02 PM   #500
x-pro is offline x-pro  United Kingdom
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I've bought 200 of (supposedly) 2SC2878 transistors on eBay, marked "C2878 GR 7E". . These are fakes. The Vebo is only about 7-10V, like on the majority small signal n-p-n transistors, and the reverse gain is only about 15-20. On the real 2SC2878 the reverse gain is over 150 (typical 250) and Vebo is over 25V (I've measured up to 75-80V). The capacitances are also different. I suspect that all transistors marked "C2878 GR 7E" on eBay from China (there are many offers at the moment) are the same fake devices.

Cheers

Alex
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