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Mystery Potentiometer Cherkfan r1610ny I'm looking for more info in ( English ) on this Mystery Potentiometer that is part of my Guitar Circuit. Can anyone help me find a data sheet in English?

Had a Google. No luck.

You need to characterise it.

1) Disconnect 2 of the three wires.

2) Using an Ohmeter, find which are the two ends of the track - not the slider - and note the resistance, R.

3) Connect a suitable voltage V across these terminals (keep V^2/R < 250mW), +V to one end 0V to the other;

4) Connect a voltmeter from 0V to the slider.

5) The slider will rotate about 300 degrees, maybe more, maybe less. Mark on a graph a horizontal axis of 0 to 300 degrees or whatever it is in, say, 30 degree steps. Make the steps equal, i.e. the horizontal axis is linear.

6) measure the voltage at those steps, i.e,; 0 degrees, 30 degrees, 60 degrees and so on up to the max rotation.

7) Plot these voltages on a linear vertical axis of your graph.

If the line you get on the graph is roughly linear voltage vs angle then you have a linear pot of value R.

If the line you get on the graph is curved then you almost certainly have a log or an antilog pot of value R. It is certainly a non-linear pot.

If you take the log of each voltage and plot them on a linear vertical axis and you get a roughly straight line then you have a log pot. The line won't be exactly straight because so called log pots are rarely exactly log all the way round. If I recall correctly they tend to turn more linear at one extreme or the other.

Have a Google/Wiki about potentiometer laws or "tapers".

Then order one like it from Farnell etc.

:)