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Re: Dropping voltage across a resistor

5/5/2006 1:42 PM
Carl Gigun Re: Dropping voltage across a resistor
Okay, thanks. To have 70v on the plate you'll need a much higher supply voltage at the other end of the plate resistor. My guess of 150v in that last post was way off. Take for example the AC15 style circuit for EF86 that uses a 220k plate R and a 1M screen R. With that circuit you'd need a supply voltage in the 250v-300v range to have 70v-80v on the plate. I measured 297v supply and 83v plate on one I had setup.  
You want to drop about 100v from your 390v supply so a dropping R in the range of 100k-120k should be about right.

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