Tube DIY Asylum

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RE: If you need precision current bias of power tubes...

Posted by Triode_Kingdom on June 5, 2017 at 08:11:47:
I dislike the idea of applying this level of control with a current source at the cathode. There's no way to know what the grid-cathode voltage will actually be at the point where the source current setting is satisfied. It seems much more reasonable to apply a fixed voltage to the cathode with a regulator, and to adjust it within a known window for the correct bias current.