An Archiphone is an electronic organ, having 31 microtonal notes in an octave.
My grandfather Adrian Fokker has built four archiphones in 1970, none of which is in a playable state anymore.
We therefore wanted to rebuild the instrument using modern technology:
a laser-cut base plate for typewriter-style keyboard keys, an Arduino microcontroller, and Midi sound synthesis.
We have build prototypes with 35 and 108 keys, and plan to do the full 341-key instrument in a follow-up project.

Here is a summary of the prototype building project.