Zoom 505II Schematics?

Had to open up my 505II to repair a cold solder joint yesterday and noticed there is a trim pot for every major effect. Does anybody here know where I can obtain a schematic or at least something that labels which trim pot is what effect? I am a little disappointed with my 505II but I think I can turn it into a hotrod if I can tweak the effects. Any help is appreciated.

I don't recomend doing technical modifications on digital units , cuz it's a real mess + you may get bad results or damage your unit.
I'm studying electrical engineering myself , and I never thought of trying to modify digital units at home.

If you have a problem within the unit (some resistors , diodes , etc. are open or not functioning) , open the unit & check these out with a Multimeter , use identical components to repair damaged ones.

Actualy poor sounds may be a result of Bad components (cheap units uses cheap components) , or Bad circuit designing (cheap units may not have the best circuit design for a given effect).