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Transistor designations

R

rkgren1

Super Member
I am looking at the Sansui service manual for my receiver to begin compiling a list of replacement transistors to buy. On several lines the text under the Description column will differ. There will be something like:

Part No. Stock No. Description
TR24 0305991 2SC403(C)3
TR25 0305991 2SC403(3)C

Identical stock numbers indicate these are the same parts. Can anyone provide some insight in the differences in the description?

I don't want to miss any relevant details and buy the wrong parts. Are the first 6 digits all I need to worry about or are the numbers/letters in parentheses important?
 
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Thanks for all the replies. I will ignore the trailing (x)x information.

I am now compiling a bill of materials to replace electrolytic capacitors and resistors on my driver board.

I can cross-reference a transistor from my service manual parts list on http://alltransistors.com and get dozens of potential references.

The list will contain data for a range of properties: PC, Uec, Ueb, Ucb, Ic, Tj, Cc, and Hfe

NPN/PNP, material, and package type are easy to match. But I do not know how to

Which of the attributes are most important to match closely?
Which are only of secondary importance?

Can you experts recommend a site to make the job easier?
 
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So Ic, Vbe and Vce are minimums as well?

Does deviating from the OEM part's values affect performance in significant ways?

Sorry for the simple questions. I am more of a nuts and bolts guy.
 
rkgren1 said:
So Ic, Vbe and Vce are minimums as well?
Click to expand...

Ic and Vce are certainly parameters that any substitute should equal or exceed, Vbe can be important, as can Vce(sat) for some applications.

But it is all a question of degree, you mustn't chose a sub with an Ic of 15A when the original was 100mA, as this means you have not chosen a suitable sub, and so on with other parameters. Then you have to understand the differences between BJT's, FET's, MOSFET's, VFET's and so on.

You won't gain a proper appreciation of what is important by asking questions here, you need to really understand how transistors work, May I suggest that you borrow a library book, or buy a book that explains all this. Oh, and when you've read a couple of such books come back here and explain it to me. ;)
 
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I am sorry to chime in so late but no one answered your original question. One I also have why is there alternate numbers and letters appended to the description. I also am redoing a Sansui 3300 and ran into the same questions. Why is there no KEY that explains what those additional numbers and letters in parentheses mean? and why is it that when people read a question they totally misunderstand what it is that is being asked.
 
I am working on an older Sansui 400, now,,, the one thing I noticed is the numbers on the schems/parts lists aren't always the same as what is in the chassis,,, I've been subbing form the parts I find in the receiver rather than trusting the parts lists!!!
 
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