I bought a bunch of linear potentiometers and I have measured them they look totally linear in all measurements, but when I attached them to a novation commercial circuit board and controlled a music program the response of the knob in the software was completely logarithmic started very slowly and went fast at the end...
that is really really weird because it means that the Novation circuit board uses logarithmic potentiometers that are converted into a linear signal which is just completely barmy. so when I attach a linear one it's converted to a logarithmic signal.
Why the hell would this insane thing happened that a manufacturer uses logarithmic potentiometers converted into a linear MIDI signal?
that is really really weird because it means that the Novation circuit board uses logarithmic potentiometers that are converted into a linear signal which is just completely barmy. so when I attach a linear one it's converted to a logarithmic signal.
Why the hell would this insane thing happened that a manufacturer uses logarithmic potentiometers converted into a linear MIDI signal?
It depends what impedance you are putting it in with. Not only the value but the shape of any pot can be altered by hanging other resistances around it. A resistor between the top or bottom and the wiper for example will have a very profound effect. Could be as simple as that!
You could check out its action very roughly out of the circuit with a DC source, (9v ish battery?), and a meter. Make sure that any impedances in the circuit around the pot are much larger than its own value to minimise their effect on it
You could check out its action very roughly out of the circuit with a DC source, (9v ish battery?), and a meter. Make sure that any impedances in the circuit around the pot are much larger than its own value to minimise their effect on it
thank you for that excellent advice, I thought that all 10k potentiometers would be the same, other than the curve, perhaps the circuit is going around the potentiometer so I should try and isolate one for measurements, and I will try and figure out what's going on with the voltage and impedance- it sounds like it takes a lot of thinking
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