<<< What do you mean exactly? What "technical innovations"?
I find the D-808 a very good receiver, but I don't know of any technical innovations.
73, Rémy. >>>
Remy, I'm not sure that you understood the original post. There are no technical innovations in the D-808 model.
These were all in the development of C.Crane's Skywave SSB model, for which the Fortuna, California company undoubtedly used a lot of research and development money to design and build a decent SSB reception system that would fit inside a very compact, Ultralight-sized cabinet. The Chinese company simply copied the innovative SSB design in their D-808 model.
Gary DeBock (in Puyallup, WA, USA)