Hi guys!
I am currently working on a Parasound 2250 (class AB), which had one defective channel. Components in the signal paths have been replaced, including an output transistor (2SC3519).
According to the manufacturer, bias is adjusted by measuring 1-3mV across the output resistors. The original ones are completely fine around 1.5mV, but the replacement is not. Initially, I got a couple from eBay, assumed they were fake (they were) and was able to source a replacement locally. This exhibits similar behaviour, being around 0.6-0.8mV on its emitter resistor....
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