30-03-2013, 12:03 PM
Ooo - that's a good stock! Don't suppose you want to sell any 
I suspect that the quiescent current would rise in fault condition - not least because there is about double the voltage across R12 and R13. If T4 or something before it is to blame, then that's probably all that's happening, but if one of the output transistors has gone leaky, the other one will be "fighting", which will cause a much larger increase.
You're probably right about T3, but obviously when you come to set up the Iq, you'll be verifying the action of that...
I suspect that the quiescent current would rise in fault condition - not least because there is about double the voltage across R12 and R13. If T4 or something before it is to blame, then that's probably all that's happening, but if one of the output transistors has gone leaky, the other one will be "fighting", which will cause a much larger increase.
You're probably right about T3, but obviously when you come to set up the Iq, you'll be verifying the action of that...
