Tests performed :
First of all, one good news : I found what was going on with keyboard mode. There was a small piece of lead shortcuting on the mode selector. Keyboard mode works fine now !
1) I don't know if VCO2 works... I get something on VR406 (VCO2 level) only when XMOD switch is on "1-2". And I only get sound on VR405 (VCO1 level) when XMOD switch is on "2-1" (and of course when XMOD volume is up a bit, in both cases. When XMOD to minimum, no sound at all, neither on VR405 & 406, nor on the x0xb0x mainboards you asked me to test earlier for VCO1).
Saw and Square switch (VCO1) makes a difference in sound on VR405 (still with XMOD switch on "2-1" and level up). Same for the VCO2 waveform switch with VR406.
2) I did not change any component in this area I guess, and it used to work fine... Diodes orientation is fine, traces seem to be OK.
3) When C1 is played...
a) Voltage is RIGHT on pad 13 now... as I adjusted TM404
. The note produced changes when I turn the XMOD knob (I guess this makes sense : the further clockwise, the higher in pitch)
b) OK : all diodes are right on the x0xI0 Top PCB, including D402. D404 is not filled.
c) TM5 seems to be 5k (reads 4.7k when completely on one side). Hard to test TM4 as I think other components are interfering. I get a 6K when power is down, but I guess this isn't relevant. However TM4 and 5 do change the tuning when I play with them.
d) OK : all those voltages (IC11 pin8, R103, Q27 emitter, Q28 drain, R45) are 11.88V
e) OK : all those voltages (IC11 pin3, Q26 pin1, R101, R36, R100A & B) are 5.33V
f) I found out that I removed C51 on the x0xb0x mainboard whereas it seems to be meant to stay... Could this be the source of my trouble ?...
Here are two pictures of the x0xb0xI0 board and the x0xb0x mainboard, just in case something obvious wound catch your eye...http://lostchild.free.fr/img/x0xb0xI0-board-1.jpghttp://lostchild.free.fr/img/x0xb0xI0-board-2.jpg