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Original Message
RE:Here is a photo of the bottom amp
Posted by sony6060 on January 11, 2017 at 22:32:44:
My bias supplies use a three section filter and a filter capacitor on the output voltage adjustment pot. It produces less than .001 volt AC ripple. I use 3K dropping resistors. At 140-160 volts initial bias voltage I would use 15K dropping resistors if it has a three section filter. 22K if a two section filter. Your transformer will supply 50ma current.
That is a estimated guess on resistor values, but supplies a stabile and stiff bias supply. I really need to see the amplifier schematic.