[R-390] OT(just a bit): From whence cometh the grid current?

[Flowertime01 at wmconnect.com]

Barry,

Screen grids are positive and there fore must suck current out of the tube.

As the voltage at the junction drops with the tube in play, more current 
must be going through the top resistor to give a large voltage drop.

Some current is diverted from the bottom resistor through the tube to allow 
the bottom resistor to drop less voltage.

Hope this helps.

Roger AI4NI