3 output vs 2 output ZVS?

[nsled]

What is the practical difference between a 3 output ZVS and a 2 output?  When driving a flyback.

Bonus question, specific to crt flybacks they have knobs on the side for "focus" and "screen", what effect do these have?

[nsled]

Well let me just say something and someone may chime in and say if it has any bearing on reality.

The 3 output ZVS draws feedback from the primary coil and will self-tune to the natural frequency of the transformer, whereas a 2 output ZVS will always have a fixed frequency?

[NyaaX_X]

I think those are two similar topologies. The characteristics of them may be some different like start oscillate frequency or something. But I think we can get almost same working when using them driving the FBT.

[Thor42]

Some Russian/Ukrainian dude have made tests, and his 2 output ZVS was weaker compared to 3 output. But I believe he did it wrong tho (5+5 turns primary vs 10 turns).