Yamaha CS80

While restoring this CS50 I thought, that a mono-unisono mode would be 
very helpful for tuning. So I am looking for a description of that 
modification (especially for a CS50). I've searched the groups archive 
for it, but did not find any details about it. I only found it mentioned 
as taken for known.

Are there any detailed explanations somewhere?

I tried to understand the principle of the KAS board, but I don't find 
any signal that resets the voice counter. I also don't find any 
significant difference between the KAS board of a CS50 and a CS60 (at 
least in this aspect).


Florian