Vintage HiFi Transistor Replacement Table
Type Replacement(s) Failure notes
--------------- ----------------------------------------------- ------------------------------
2SA706 KSA1220 or 2SA1837 or KSA1837 Gain deteriorates with age
2SA720 KSA1013
2SA725 KSA992 or BC327 Shot noise
2SA726 KSA992F or KSA992E or BC327 Shot noise
2SA798 (2x) BC560B or (2x) KSA992
2SA809 KSA1381 Poor heat dissipation
2SC458 2SC2240 or KSC1845F or KSC1845E Leakage, noise, static
2SC631 KSC1845 (but test for hfe 350+) Prone to failure or noise
2SC632 KSC1845 (but test for hfe 350+) Prone to failure or noise
2SC871 KSC1845F or BC550C Leakage, noise, static
2SC1000 KSC1815Y Leakage, noise, static
2SC1124 KSC2690 or 2SC4793 or KSC4793 Gain deteriorates with age
2SC1312 2SC2240 or KSC1845 or BC337
2SC1313 2SC2240 or KSC1845 or BC337
2SC1318 KSC2383Y or KSC2690AY Thermal stress, thermal flex
2SC1344 2SC2240 or KSC1845 Static burst
2SC1345 KSC1845
2SC1400 KSC1845
2SC1451 KSC3503 Static burst, open circuit faults
2sc1000 replace
2SC458 & 2SC1000 you could use ---2SC1815-------KSC1815
http://www.mouser.com/ProductDetail...GAEpiMZZMsTKkj12KWLXuW5oDYpP%2bzxGbXKcGxnyRY=
2SC458-----KSC1845 -- higher voltage
http://www.mouser.com/ProductDetail...GAEpiMZZMsTKkj12KWLXuW5oDYpP%2bzxSlkrctCof5s=
Better Hfe gain numbers
http://www.bdent.com/2SC2240BL-p/2sc2240bl.htm
Use 2SC2240BL for both 2SC458 & 2SC1000..
2SC1000 is a very low-noise transistor which can't be replaced by an el cheapo 2SC945 - take a 2SC2240 (2SC2547 or 2SC3198) instead. For the 2SA493 take a 2SA970 (2SC1085 or 2SC1048).
For 2SC1000 I use Toshiba 2SC3329BL, much lower noise. For 2SA493 I use 2SA1084 made by Hitachi or Renesas.
