Royal Expert
Multiplex Royal Expert c. 1987 (not sure of the exact date).
The evolution from the Profi 2000 is that there is no plug in module. Instead, all of the trim pots, dip switches etc. are permanently on the encoder board and all you change for different applications is the EEprom with its dedicated template. Then the trim pots would change function according to the EEprom installed.
Encoder Board
Here is the encoder board. On some of them, you had memory so that when you went back to a certain aircraft or helicopter, all you had to do is recall the memory in that particular EEprom.
Again, like the 20 year old Profi 2000, one transmitter could do gliders, aerobatic aircrafts, and helicopters.
With the Royal Expert shown here, there were a lot of different EEproms availlable even a Nautical one. Way ahead of its time - when all others merely had end point adjust and servo reverse.