Fake 2SA1943

[sam9]

I am convinced I have been victimized by fake 2SA1943's. I don't think these were reported ealier. I'm sorry to say I bought them from "Match-A-Knob" because they seem like nice people who are probaly victims asw well.

I'm not in a state to type the whole story out again so the following is a copy of what I sent to Rod Elliot since he seems to be the a central clearing point for this matter. You can only imagine how it feels to spend days trying to find an assumed error of one's own only to discover that it is some #$^*&^%$ that's the cause.

Here's the e-mail to Rod Elliot:----
I regret to report to you that you may now add 2SA1943 to the list of possibly fake transistors.

My story will probably sound familiar. I was powering up an amp of my own design (more or less) for the first time when the fuses blew. I removed the output devices and discovered that one had failed short. I checked the schematic and the pcb layout for design/construction errors. I did this twice. I first decided that the fault was mine since earlier I had a small problem because of forgetting a sil-pad (though not on the failed 2SA1943). But also felt that the circuit and layout were essentially OK – it wasn’t THAT original. I try to power up again and when the rails reached ~35V the prior story repeated. I was still inclined to suspect my own ineptness but on a lark, I smashed open one of the 2SA1943’s if only to alleviate my frustration.

What I found looked exactly, I MEAN EXACTLY, like the photo on your site of the inside of a fake 2SA1302. I conclude it’s the sam *******s just printing a different label on the package, At first I just thought I couldn’t find the die or didn’t know what I was looking for. Then I saw this 3mm x 3mm square thing pasted on with white glue. There is a clue on the outside. On a real one (I sacrificed one just be sure) the Toshiba label is typically hard to read on the dull surface. On the fake the surface has a glossy area where the label is quite clear.

The 2SC5200s from the particular supplier seem to be real. They don’t die when abused and the exterior is dull flat black, somewhat difficult to read unless the light is right.

Since I don’t have a digital camera, I will send you one of the offending items so you may confirm and report.

I hope the above is coherent because to tell the truth I’m so steamed I’m ready to smash something besides just the transistors! To use a phrase from an old Monty Python sketch, I’m sitting in the corner biting the heads off wickets.

Marc Whitney