Hello I bought a used GFA 545
One channel is totally fine,
I've measured a 150mv bias current across TP1 and TP2 in the faulty channel (should be 6.5) There is audible distortion on that same channel There is no extra noise when no music is playing
Can someone help me troubleshoot this problem? Thank you
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One channel is totally fine,
I've measured a 150mv bias current across TP1 and TP2 in the faulty channel (should be 6.5) There is audible distortion on that same channel There is no extra noise when no music is playing
Can someone help me troubleshoot this problem? Thank you
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driver Q621 leaky
thermistor 601-problem
Q 617 - 619 leaky
C607 leaky
VR 601 open or other
Could also be a combination of the above
Thank you! R645 (Q625 E pin) is reading 150mv, thats where the bias is coming from, no other output emitter resistors have that voltage does that narrow it down? It's receiving proper voltage, so that means its q625 gone bad?
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