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Transistor Substitutions

Wow… 3503 is out of stock? Shall I buy ~100 pcs for future porposes? For now I can easily buy the korean KTC3503+KTA1381 for 2$.
 
I recently had a need to replace a 2SC1416. The recommendation from the thread was to use a KSC1845. The 2SC1416 on my board had a TO-1 package that put the base pin was in the center. The KSC1845 has the base pin on the right. That was going to make installing it a challenge. I had good luck with the 2N2482 with a TO-18 package. The base pin was in the center. The technical specifications were close to the original 2SC1416 that was used from the factory.
 
Kbob1001 said:
I recently had a need to replace a 2SC1416. The recommendation from the thread was to use a KSC1845. The 2SC1416 on my board had a TO-1 package that put the base pin was in the center. The KSC1845 has the base pin on the right. That was going to make installing it a challenge. I had good luck with the 2N2482 with a TO-18 package. The base pin was in the center. The technical specifications were close to the original 2SC1416 that was used from the factory.
Click to expand...
Not really close....

Screenshot (745).jpg
 
You are correct. I wrote down the wrong part number. I should have wrote 2N2484. If this is a bad choice for a replacement, please let me know. Any knowledge you can pass my way would be greatly appreciated.
 
Kbob1001 said:
You are correct. I wrote down the wrong part number. I should have wrote 2N2484. If this is a bad choice for a replacement, please let me know. Any knowledge you can pass my way would be greatly appreciated.
Click to expand...
Get yourself some fiberglass sleeving to use if you need to cross transistor legs in the future.

IMG_20251207_210158501.jpg
 
Thank you for the feedback. I did not know about the trick with the fiberglass sleeve. I will definitely look to find some for future needs.
 
Hello, does anyone have a tip for replacing the 2SA968Y/2SC2230Y driver transistors?
Thank you Pavel
 
Hi,
satpaul said:
2SA968Y/2SC2230Y
Click to expand...

Did you mean 2SC2238Y?
I think you need some TO220 parts. One option is the KEC pair KTB1369Y and KTD2061Y. These are the closest match you could possible find, and are rated at 2A collector current, VCE =180V and have a 100 MHz transition frequency like the original toshiba parts.
They are fullyninsulated so you need a workaround, but that is manageable.
Check with Profussion audio. I think they are in stock there.
 
My apologies for the potentially dumb question (big newbie here), but I have had a quick look on mouser and digikey for 2SC1451 & 2SA726 replacements following recommendations from post #1, but I can't find an exact match for the parts.
For example mouser has KSA992FTA but no KSA992 and I don't understand if those two have matching specs or if there is a difference. Datasheets I try to consult for the -FTA model are always titled "KSA992", so ... probably those are the same ? Then why the different naming scheme ?
I'm wondering the same for KSC3503 & KSC2690AY. First one seems discontinued, second one I find the same thing as for KSA992, slightly different naming scheme.

Again, sorry for the dumb questions.
 
The F is the gain rank. TA is tape. BU is bulk. Or something like that. It's on the data sheet.
 
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Looking for replacements for 2SA1383 and 2SC3514, I came across a recommendation (in this Sony TA-N80ES repair thread) for 2SA1930.

A significant spec difference is the output capacitance. For the original 2SA1383, it is spec'd at 4.5 pF. For the potential replacement, 2SA1930, the spec is 26 pF.

EDIT: The ft for the 2SA1383 is 180 MHz typical, for the Toshiba 2SA1930 I'm looking at it is 200 MHz.

The application the 'Class B Power Amp' 2nd stage in my Sony ES amp. These devices drive an SC2275 / 2SA985 push-pull pair through 10 ohm, 1/2 W base resistors.

Does the difference in capacitance matter? These devices are hard to replace...

Thanks
Tim
 
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