Hi everyone. I do not quite understand what happens with this equipment. I am working on one channel, the other does not work and has missing parts. I do not have enough current at the base of Q1 and Q3 dirvers. By disconnecting the D1 (STV 4H), it barely exceeds the bias current suggested by the service manual. I am using a variac and lamp in series to perform this test. As it was not destructive, connect the amplifier directly to the power outlet, but without any positive results. What I did find is voltages different from those indicated in the manual, in the collectors of Q3, there are 21V instead of 12.1, therefore, in the emitters of Q5 there are 21.4V. Try to exchange Q1, Q3 and Q5 with those of the other channel, but the fault persists, the rest of the voltages are correct. Currently, disconnect the bases of Q5 and the voltages in the collectors of Q3, they remain in 21V Any suggestions?
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