Yamaha B-1 problem.

[javad]

Hi everybody,
On my B-1 yamaha amplifier, I replaced 4 output transistors 2SK77 with 2SK180. My amp now is in protection mode.
Can anybody help me to remove the problem?

cheers, Javad

 

[elrod]

You may get better reply's if you post this in the Yamaha forum. I'm no tech but did you find the issue that caused the 2SK77 to blow or did someone steal from Peter to pay Paul, and you're trying to get Peter running again. There are some component changes (which I don't know what they are) to use the 2SK180's in place of the 2SK77's. Do a search in the Yamaha section and you may find something...

By the way, welcome to AK!

 

[javad]

Dear Elrod,
Thank you for your reply. I am not sure about the reason. By the way, thank you for your advise.

All the best,
Javad