What think ye?
Purpose: increase the output voltage range of an emitter follower. Like, the complementary follower in the output of an audio amp. But maybe not for audio, but for 50 ohm loads, hence the need for high voltages.
Since, obviously(?), no 500V+ RF transistors exist*.
And of course, doing it straightaway means possibly DC coupling, no need for a matching transformer.
*Some MOSFETs do. But then, they're rather botique, and not nearly as fast as lower voltage parts. So, you're not going to get maximal bandwidth that way.Difficulties include more voltage gain stages, of differing gains (to drive the "center taps"). Or bootstrapping the cascoded sections.
Or, if you have a particular power bandwidth to accommodate, maybe it would be okay to run the cascodes from voltage dividers, without compensating their capacitance; the output stage simply saturates if you demand too much HF power from it, but does slower moving signals at full amplitude. Example, a function generator with a wide DC offset range and no derating of amplitude (as long as Vpp < Voffs) versus frequency or offset.
Tim