I am repairing an older Emotiva amplifier. In one stage it uses a 2SC4793 (NPN) and 2SA1837 (PNP) complimentary pair. These transistors are obsolete. I have read that they can be replaced with TTC011B and TTA006B, respectfully. Mouser has TTC011B in stock, but I can’t find anyone who has TTA006B in stock. Is there a reputable source where I can purchase the TTA006B? If not, is there another complimentary pair I can use instead?
Thanks.
Thanks.
Mouser will have some in July, if you want to wait for the exact part.
I used the Digikey search to narrow down based on the highlighted features of the TTA006B:
This search eventually led me to the NTE 2647 and 2648 complementary pairs. Perhaps they would work? Check the specification sheets. Heck, Emotiva might even answer a question, and garner some Positive Vibes.
Kind regards,
Drew
I used the Digikey search to narrow down based on the highlighted features of the TTA006B:
- Vceo = 230V
- fT = 70MHz
This search eventually led me to the NTE 2647 and 2648 complementary pairs. Perhaps they would work? Check the specification sheets. Heck, Emotiva might even answer a question, and garner some Positive Vibes.
Kind regards,
Drew
2SC4793 (NPN) and 2SA1837 (PNP) are TO220, pinout BCE.
TTC011B and TTA006B are TO126, pinout ECB and lower power rating.
Not direct replacement for me.
If you can live with 150V or 180V, I would use Sanken 2SC4883(A) / 2SA1859(A), which are just as good.
Available from Digikey.
If you must have 230V then only MJE15032 / 15033, with lower hfe and fT.
Patrick
TTC011B and TTA006B are TO126, pinout ECB and lower power rating.
Not direct replacement for me.
If you can live with 150V or 180V, I would use Sanken 2SC4883(A) / 2SA1859(A), which are just as good.
Available from Digikey.
If you must have 230V then only MJE15032 / 15033, with lower hfe and fT.
Patrick
You can replace the 2SC4793 with the 2SC2336B, 2SC2898, 2SC3310, 2SC3868, 2SC4242, 2SC5241, 2SD772B, 2SD792B, BUX84, BUX85, MJE13070, MJE13071, MJE15032, MJE15032G, MJE15034, MJE15034G, MJE16002 or MJE16004.
You can replace the 2SA1837 with the 2SA1006B, MJE15033, MJE15033G, MJE15035, MJE15035G, MJE5850, MJE5850G, MJE5851, MJE5851G, MJE5852 or MJE5852G.
You can replace the 2SA1837 with the 2SA1006B, MJE15033, MJE15033G, MJE15035, MJE15035G, MJE5850, MJE5850G, MJE5851, MJE5851G, MJE5852 or MJE5852G.
I wouldn’t stray THAT far from the originals - I’d stop at the 1503x series as far as “compatibility” as audio drivers. The 1307x, it’s derivatives, and PNP complements are high power switching transistors with MUCH lower gain. Using them to replace sustained-beta drivers directly will result in noticeable degradation. I have used them as drivers, and even VAS— when the circuit was designed for it using darlingtons or cascodes and I absolutely needed a 400 volt transistor. +/-165 volt rails will do that….
The alternate 2SA/C numbers are just as obsolete and just as likely to end up being faked. I would consider alternatives from Sanken - whatever Digikey may have in stock at the moment. Just as likely to run out of stock on those as the Toshiba TTA006, though.
2sa1837 ,2sc4793 is made by UTC , a legit semiconductor firm in Taiwan, sold by Profusion in UK. We use them in production amplifiers, and they are fine.
In fact UTC makes a number of popular transistor types, just search transistors on Profusion site.
In fact UTC makes a number of popular transistor types, just search transistors on Profusion site.
It’s about time SOMEBODY stepped up and started providing alternatives for old Jap types that won’t blow up the instant you turn it on. Makers like Mospec started doing it with the 2N types 2 decades ago now. wonder when/if Mouser and such will start carrying some UTC - or of they’ll ever bring back some of the TO-3’s from Hell like the D424 (fat chance?).