03-21-2015, 07:30 PM
Yes, I agree with Morzh. From the readings you gave, there appears to be little or no bias on the output stage. Place your DVM across the .47 ohm emitter resistor and adjust the bias pot VR7 and VR8 so there is 10 mV of DC measured across each resistor with no audio signal. If you have the service info, set the bias as they specify.
This will provide a constant minimum DC current through the output transistors, keeping them on as they switch polarity of the output signal and minimize the class B crossover distortion.
This will provide a constant minimum DC current through the output transistors, keeping them on as they switch polarity of the output signal and minimize the class B crossover distortion.
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
