Audio Pro B2-50 - ADJUSTMENTS; Bias Adjustment in Power Amplifier

3. ADJUSTMENTS
After certain repairs have been made in B2-50, the following
adjustments must be performed.
3.1 Bias Adjustments in Power Amplifier
After repairs have been made in the Power Amplifier, the bias
current must be readjusted.
Measure the voltage between emitters on V516 - V517 (no
signal on input terminals of B2-50). Adjust trimpot Rqc (R525)
till voltage reads 22mV. (This corresponds to a bias current
of 50mA).
Make final adjustment after B2-50 has been ON for a few minutes,
so the bias current has reached steady state value.
NOTE: When replacing power transistors, temperature sensor
on V508, heatsink compound (and isolating shims) must
be used.