via Adrien:"i found in an old french book about synthesis (from Jean-Paul Verpeaux) a picture of a 'yamaha FM synthesis prototype', clearly looks like a DX-1, with some differences quality is very bad, i'm sorry, but, i don't think i've ever seen that picture"
Be sure to click the image for the full size shot and zoom in a bit. The scan actually isn't too bad in that you can read the text and you can clearly see the label CSDX. If anyone can translate this feel free to post it in the comments or send it my way. You can find my contact info on the bottom right.
You can find all posts on the CSDX here.














































