Is this the voltage 'across' the resistors?
If so, you don't need to give the polarity unless you stated which ends of the resistor you had the probes on.
Is R331 out of tolerance? If not, is it significantly hotter than R330?
Yes this is the voltage across the resistors.
I didnt notice it getting hot, I will check the tolerance and temp.
Is R336 within tolerance?
R337?
The protection circuit is engaged. It thinks there's excessive voltage across R336.
If you can't find the fault, lift D302 again and set the bias. Then measure the DC voltage across R336 and R349. They should be virtually identical. If they are not, the one with greater voltage is likely out of tolerance.
R337?
The protection circuit is engaged. It thinks there's excessive voltage across R336.
If you can't find the fault, lift D302 again and set the bias. Then measure the DC voltage across R336 and R349. They should be virtually identical. If they are not, the one with greater voltage is likely out of tolerance.
I had already replaced R337, and its still within tolerance.
I checked both R336 and R349 both tested within tolerance in and out of the circuit. I replaced them anyway and that fixed the problem.
The channel now will bias and produce clean audio.
I find it strange that components can test ok but still be bad, very strange.
I do remember a previous 4 channel amp you helped me with, something similair with a resistor that tested good and wasnt getting hot with excess voltage running across it but it was bad, even though tested good in and out of circuit.
Thanks as always Perry.
I checked both R336 and R349 both tested within tolerance in and out of the circuit. I replaced them anyway and that fixed the problem.
The channel now will bias and produce clean audio.
I find it strange that components can test ok but still be bad, very strange.
I do remember a previous 4 channel amp you helped me with, something similair with a resistor that tested good and wasnt getting hot with excess voltage running across it but it was bad, even though tested good in and out of circuit.
Thanks as always Perry.
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