Farfisa Compact Combo repair problem

[calpurnia65]

Hi, 
I'm trying to restore my 1960s Compact Combo, and so far, it definitely has a few problems. It was stored in a damp basement for a number of years. The keys for D#, E, F#, A#, B, and C# all play the wrong notes. I have some basic electronics knowledge but I'm no expert when it comes to transistors or fixing organs. Any help with this would be greatly appreciated. 

[RadioWave]

I would check the resistor and capacitor values before digging in to the transistors. Otherwise your other option is to find a complete tone generator card on reverb or ebay. Sadly it might be long time before one pops up. I always keep a "parts organ on hand for parts to keep my duo compact running.