Ronito
1
Hello Tweakers 
I wonder if anybody can help with a diagnosis .. 
My Roland TB303’s envelope knob seems to have died, all other knobs tweaking but the env nothing.
doesn’t seem to be the knob itself, could it be a component or transistor or something?
Thank you folks 
Worth gong through the service manual for this and getting hold of a replacement pot.
Ronito
3
many many thanks sargfowler! your advice much appreciated
Ronito
4
all fixed thank u. will replace all the pots when i get a moment.