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question on ohm's law

If I want to reduce the B+ voltage going to the plate of a driver tube with a resistor, what value for the current do I use in ohm's law? Is it the plate current for the tube (say 6mA for a 26) or do I use some other value?
For example, I have a full B+ of 400vdc and I want it reduced to 110vdc at the plate of a 26, that's a drop of 290vdc. Plate current for a 26 is 6 mA. Is the right way to calculate R to divide 290vdc by 0.006 to get 48.8k ohms?
I ask this because what I am calculating and what I am getting when I measure it are very much different. I am getting almost no reduction in voltage when I measure it using a 48k resistor between the B+ source and the plate of the 26.
I am guessing I have something wrong in theory or practice, but I don't know what.

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Topic - question on ohm's law - vinnie2 05:31:38 04/26/16 (42)
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