Transistor subs for 2SC1573-Q, 2SA666A-AD3, 2SC828-R for Technics SA-5350

[Ed Whibley]

Hello, first time looking for subs for the following transistors on Technics SA-5350. These are the part numbers in the service manual: 2SC1573-Q, 2SA666A-AD3, 2SC828-R.

Here is what I've found, but it's my first time trying to find subs as I'm new to this hobby. Hoping someone might know if these are good selections from Mouser (Mouser part numbers), many thanks in advance. -Ed
2SC1573-Q - NTE157
2SA666A-AD3 - 512-BC556ABU
2SC828-R - 2N3904

 

[JoseHH]

For 2SC1573 is better to use the KSC3503 from mouser or digikey. It is a TO126 part but it meets or exceeds the characteristics of the original part.
Another alternative is the SANYO 2sc3468 which is equivalent to the 2sc1573.
For 2SA666A use KSA1015Y or KTA1266 rank GR or Y
For 2SC828R use KSC1815Y or KTC3198 rank GR or Y
Check mouser or digikey to see what is in their stock.

 

[Ed Whibley]

For 2SC1573 is better to use the KSC3503 from mouser or digikey. It is a TO126 part but it meets or exceeds the characteristics of the original part.
Another alternative is the SANYO 2sc3468 which is equivalent to the 2sc1573.
For 2SA666A use KSA1015Y or KTA1266 rank GR or Y
For 2SC828R use KSC1815Y or KTC3198 rank GR or Y
Check mouser or digikey to see what is in their stock.

Superb! Thank you so much for the help. What is most important when looking for subs? HFE C-E?
BTW, Does AudioKarma have a database of Transistor substitutions? Or is that asking for trouble to keep it correct?

 

[JoseHH]

There are several listings of substitutions. But they get obsolete quickly because of parts being discontinued.
Search "transistor substitutions" and " top ten worst transistors" and "failure prone transistors".
That thread has some recommendations that answer your questions:
Wuth regards of what is more important hfe or vce? It depends on the location of the transistor in the circuit.

Top Ten Worst Transistors - noisy, failure-prone, whatever... and replacements

I've followed AK advice for several vintage solid state receivers now and the difference in sound, from recapping and from replacing "known-to-be-noisy" small signal transistors to be amazing. While following along with others' threads and trying to help out with "consider replacing these...

audiokarma.org

 

[dlucy]

"Lists of transistor substitutions" sometimes disappoint because a proper substitution takes into account how that transistor is being used in a given circuit and not just the model number of the transistor. So, if you find an old 2SC1315 has a modern substitution of KSA1845F (in general from a non-model- or circuit-specific list)... but you fail to look at how it is used and in this example the 2SC1315 commonly gets 300mA... but the KSA1845F maxes out at 100mA... then you may well be disappointed with the results.

So, non-application-specific transistor sub lists are fine starting place, but be aware they are not always correct for your specific use.

Good luck!