I got a good look at the new BE 50 kW AM rig at NAB this week. Co-designer Jerry Westberg went over it w/me, looks pretty interesting. A new idea for higher efficiency ham amplitude modulation? Nah. They ditched class E and went for even higher efficiency using RF PWM, generated with DSP. Unless you guise want to wind your own DSP code, this thing would be tricky to try and build at home. There is no power transformer, and it has a bunch of switching power supplies as well as RF modules. Output combiner is simple summing network with T transformation. He used litz wire for the inductors and big micas for the caps. Did i mention that its supposed to run 88% efficient from line in to rf out? Also, it weighs about 1100 # total, and covers the same footprint as the old Raytheon RA1000! It should give the Harris digital 50 a run for money, as it looks simpler and cheaper to build....
Interesting that Continental did RF PWM (and had an expired patent from 1982) with years back and abandoned that. Didn't have the DSP power that can do a lot more now in creating pulse width variations for the RF carrier in response to modulation. It is NOT a solid state ampliphase.