Hi,
I have built a stereo amp using 1xK8084 pre amp, and 2x K8060 amps using the correct transformers.
All has been well for some time and this amp has given very good service, however today after switching on and leaving for about 5 minutes one of the K8060 produced a VERY loud hum and has stopped working.
If switched on all I get is this very loud hum.
The other amp and pre amp are fine.
Help.
Difficult to say, it can just be anything.
In these cases, we usually replace all transistors, this is the most effective way of troubleshooting this amp.
Make sure bias is correctly adjusted and make sure power transistors are correctly mounted and cooled.