Vincenzo and Gordon,
Previously I traced my way through much of the circuit diagram, and don't remember seeing the pitch/dco/vcf bend signal going there. However, the circuit diagram in the PDF manual is fairly hard to see...
To add to the discussion I have voltages at IC 17 reading from ground. No voltages changed for any joystick position (my broken joystick does nothing at all to pitch/dco/vcf). Bend slider was at 100%. My multimeter is a crap analog one. Readings are approximate.
IC17
Pin 1: +3.6v
2: +2.0v
3: +2.0v
4: +3.6v
5: +2.5v
6: +2.5v
7: 0v
8: +2.5v
9: +2.5v
10: +4.8v
11: +2.5v
12: +2.5v
13: +4.8v
14: +4.8v
Vincenzo - If you are able to probe voltages using a multimeter, I can walk you through what I did in the original email. We might be able to narrow this thing down for both of us. In general, I can see my joystick changing voltages for north-south and east-west from KLM-699 board to KLM-696 board and into IC 6. Pitch bend sort of "dies" in IC6. DCO/VCF signal appears to leave IC6 and go to I39, I38 and (maybe?) IC10.