Qud EL84 Screen Resistors

[TUBEDUDE]

not to hijack the thread, but have many of you tried the two resistor divider method of Vsc control? if you have, do you also use a screen resistor before the divider, or do you just use the divider to track the screen voltage tied to the plate?

[Colossal]

not to hijack the thread, but have many of you tried the two resistor divider method of Vsc control? if you have, do you also use a screen resistor before the divider, or do you just use the divider to track the screen voltage tied to the plate?

Yes, I have used and use it. Andy Le Blanc wrote extensively about this. I use a C-R-C or C-L-C (depending on the design) where the screens are feeding off the second C. No dropping resistor coming off that second C, just B+2 into the resistive divider.

[TUBEDUDE]

Colossal, doesn't the string need a second resistor to establish a ground reference so the Vgs tracks Vp?

[Colossal]

Colossal, doesn't the string need a second resistor to establish a ground reference so the Vgs tracks Vp?

The base of the divider is going to ground. So, you have the C-L-C of the power supply. From the second C (which is B+2 Screens), voltage goes to the divider. Bottom leg of the divider goes to ground. The screen resistors are the top of the divider.

Am I missing what you are asking

[TUBEDUDE]

Ok. By the initial description I misunderstood it to mean a separate CRC as going just to the screen from the plate. I gotcha now.