03-16-2016, 08:46 AM
Sometimes, not often, crackling sounds are made by resistors that are on the way out. I have seen this a couple of times in AA5's where the screen resistor on the audio output (50C5) fails and that crackling sound is a warning about that resistor about to fail.
Do you have a scope? If so, start at the speaker and work backwards until your scope shows a "crackle-free" signal. At that point you have just passed by the defective stage. Look for the defective part in that stage.
Do you have a scope? If so, start at the speaker and work backwards until your scope shows a "crackle-free" signal. At that point you have just passed by the defective stage. Look for the defective part in that stage.
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