> I am completely ignorant about component of singles modules of
> system A 100. I use intuition and poor memory of school to
> understand.______In wich kind of modules i can find potentiometer
> 50k....100k How i can connect it Thank Robert

I did not mean to use the potentiometer of an existing module but to take a spare part potentiometer in the 50k...100k range and connect the end terminals to +12V and -12V. At the center terminal one obtains an adjustable voltage in the range -12V...+12V. This could be wired to a 3.5 mm socket (via a 1k protection resistor) to have a simple CV source -12V...+12V aivailable. All elements are available as spare parts from us (potentiometers, sockets, 8HP blind panels - even punched like A-176 for 5 x potentiometer and 5 x socket without printing).

Best wishes
Dieter Doepfer