Just work it out. If the load resistance is 0.5 ohms, the load draws more current (3.33 amps vs 2.5 amps before), but it’s less power, because the voltage has dropped: it’s now only burning 5.55W.

On the left half of my LTSPICE capture of the K2-W’s input stage schematic, ... while the second triode’s plate is connected to +300 V DC via a 220-kΩ load resistor.

Looking into the primary of this transformer, you should see a load equivalent to 1/100th of the secondary’s load. In other words, the current out of V1 should be the same as a 1 ohm resistor.

I “efficiently” did a preliminary LTspice run on the left half of the schematic to establish the average current in the coupled-cathodes’ resistor to −300 V DC.

A disadvantage is that it is a slow interface, and it is pretty weedy – reducing the 1M resistor reduces the output voltage. Reducing the 2k2 input current limiting resistor can make it stronger. An ...

Yesterday’s idea for a Cuk converter synchronous rectifier drive (right) seems to work, according to my use of LTspice. But it needs a rather low value (100Ω) R1 resistor to pull against R2, the 330Ω ...