Chris Morriss wrote:


I hadn't thought about using the grid current to offset the flux
produced by the anode current of the driver! You're right, a bifilar
interstage has to be connected in the correct phase. You can do the old
GEC trick though to extend the HF (and used nowadays in the SEPIC dc-dc
convertor topology) of using a capacitor together with the transformer
to short-circuit the leakage inductance. (Only works if the transformer
is *exactly* 1:1 of course.

I have seen that cap trick used with cheap allied interstages as well.

--
Nick