I’m no engineer, just a failed radio presenter, but I always found it strange that RNI brimmed with multiple RF outlets (not wilt standing the jamming, multiple frequency changes, blah, blah, blah) that they there was no significant effort to improve the audio, or antennae matching, considering the 4 years at sea and significant backing not enjoyed by Caroline for instance. Willing to be shot down in flames.
You would be hard put to find an Ampliphase still in service anywhere in the world today but there are loads of Doherty amplifiers, and I am not just talking about the likes of the Marconi B series at the BBC AM networks. There are Doherty amplifiers for mobile phone base stations, satellite and microwave links and digital TV and DAB networks and so on.
Ian, I am sure that Robin told me the RCA 100 kw was a prototype built in Italy.