regulator in AR D70


Hallo ! The screens are fed from a single 6550 tube , about
335 VDC . Also a TIP 41 powertransistor gets this voltage to its collector and in turn feed the 6FQ7 tubes with 327 VDC.
A Darlington trans. , D40k1 is connected to the base of TIP41
and finally an OP , TL071 feeds this Darlingtontr. My PROBLEM is that these transistors seem to be fully open and I get almost 335 VDC out from the "TIP". Which component can I suspect to be wrong ? Which voltages except those I mention are critical ? R80 , 27K , passas almost 12mA . Shall the voltage over this resistor be about 311 VDC ? Well , thanks for some help . The TIP 41 is checked outside the unit and it was OK .... Stewen
stewen1

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