What's needed is a PNP valve!
Active pull down is what's in order though it gets complex if doing it with valves. I've seen operational amplifiers using hollow state, but if you'd have to go that far
Using sand for a load you could do better with a constant current sink than just a resistor.
Transformerless class A P/P stage possibly? May be interesting! But a pig to drive, and would definitely need separate filament supplies....
There may be something from the world of video signals processing that would be a help...
Active pull down is what's in order though it gets complex if doing it with valves. I've seen operational amplifiers using hollow state, but if you'd have to go that far
Using sand for a load you could do better with a constant current sink than just a resistor.
Transformerless class A P/P stage possibly? May be interesting! But a pig to drive, and would definitely need separate filament supplies....
There may be something from the world of video signals processing that would be a help...
