Hi lim0nade,
If the noise and offset of the amplifier are still small enough not to be an issue to you, then you could conclude that the damage to Q6 isn't too bad and just leave it as is.
If not, Q5 and Q6 should preferably be replaced with 2SA970GR's from the same batch, but I gather those are not available anymore. KSA992 is still available, has the same pin-out and should do the trick.
Regards,
Marcel
If the noise and offset of the amplifier are still small enough not to be an issue to you, then you could conclude that the damage to Q6 isn't too bad and just leave it as is.
If not, Q5 and Q6 should preferably be replaced with 2SA970GR's from the same batch, but I gather those are not available anymore. KSA992 is still available, has the same pin-out and should do the trick.
Regards,
Marcel
I was under the impression that you were recommending another type of transistor rather than replacing one 2SA970GR with another.
Regards!
Regards!
An alternate type is just as likely to suffer EB breakdown, so it’s just a matter of whether a Toshiba is shipping 2SA970’s anymore. Fairchild KSA992 is available ATM, and would be preferable to an A970 that’s developed 1/f noise.
I dont trust anything TO-92 to be there long term. You’ve got to check on almost a daily basis if you can even get them. Anyone seriously still considering using them for repairs or new builds ought to just get a stash ASAP if they don’t have them already. It may be too late when an EOL notice does go out. A couple hundred is just a good investment - and we’re talking about dinner money here. One miserable pizza night. If you are using thousands you probably have some sort of income stream from it so you can afford thousands.
I dont trust anything TO-92 to be there long term. You’ve got to check on almost a daily basis if you can even get them. Anyone seriously still considering using them for repairs or new builds ought to just get a stash ASAP if they don’t have them already. It may be too late when an EOL notice does go out. A couple hundred is just a good investment - and we’re talking about dinner money here. One miserable pizza night. If you are using thousands you probably have some sort of income stream from it so you can afford thousands.