So what we need :
-DREMMEL or sandpaper
-pernament marker
-whitespirit or some aftershawe
-PCB kit
-superglue
So apply superglue on this points (ur joy stays together
)
Now U can disassemble the bottom piece of joy (metalpiece and PCB).
Take old PCB and cut newone from new PCB in same shape.
Drill out same holes too.
Now U have something like this (click for zoom) :
Assemble this newone PCB back to joy and move with it around for minute.
Ok now take the PCB out and find scratches from joys contacts on it.
Take pernamentmarker and draw the conductors.
Here U can see drawing and scratches on finished PCB (click for zoom) :
Put newPCB with drawing in etching liquid. When it is done put the new PCB to joy and test it out (just move with it around ). Take it out from joy and U can see scratches on pernamentmarker drawing. If everything is ok make PCB clean with whitespirit or aftershave.
Solder wires on PCB and assemble joy back to one piece.
Work done !!! goodluck to all.