pitch bend

[Amwilburn]

Your range is correct, 0 to 127, but the 'rest' value is 32 instead of 64... I think Chris (overover)'s assumption that you have a logarithmic rather than a linear potentiometer. I know you said that your pot is labelled correctly, but Chris also included a post with a link to buy the correct pot (in Germany)

If you set pitch to 0 and everything is fine, then everything points to the calibration of the pitch bend wheel; but since the range is correct, it points to what Chris said; logarithmic pot.

[mikf]

 Mark, it has nothing to do with range. When I use an expression pedal to bend pitch I don't think it moves the potentiometer. My assumption is that the pedal acts as the potentiometer, while the one attached to wheel is bypassed. The range is set on the system. So if it still happens when using a pedal rather than wheel it can't be the internal potentiometer - at least that seems a logical conclusion to me.
The question for the OP is whether he has tried using an expression pedal to pitch bend and what happens. I think he is saying it still does the same. But it's a little difficult to be sure exactly what he is saying.
If it really does do the same, the cause may be buried elsewhere in the system rather than the wheel/ potentiometer. Maybe a capacitor like he says, or another electronic component. Finding that seems like a job for a very knowledgeable tech.
Mike

[werikas3210]

  I am very grateful for your advice and help. The potionciometer is now new and according to the Tyros4 manual, I'm sure I've already tried three potionciometers, the result is the same, nothing has changed.
I don't think that the potionciometer is to blame here, because it is installed according to the code as it should be.
Apparently nobody has encountered this problem, unfortunately it happened to my Tyros4.
My only guess is that some capacitor could have gone out after many years and changed half the tone, but that's just a guess.

[KurtAgain]

Hi Rolandas,
The problem may be caused by an incorrect setting for the external controllers. Or a controller is defective. To check this, disconnect all footswitches and expression pedals from your Tyros (the 3 jacks labeled "Assignable Foot Pedal") and see if the error still occurs.
Kurt

[werikas3210]

   Hi, I have only one pedal and I don't use it at all, it's always disconnected. Unfortunately nothing changes. I was only briefly connected - it works the same as the pitch bend wheel.
Thank you,
Rolandas

[KurtAgain]

It would have been too easy if the cause was simply a defective external device.
Kurt

[werikas3210]

  I noticed another strange thing - when I bend the pitch bend wheel forwards, the notes are lower. And when I bend the pitch bend wheel backwards, the notes go up. It used to be the other way around, a very strange fault.
How could this happen, and after replacing 3 potionciometers, still the pitch bend is not working correctly, nothing changes.
I have an old yamaha psr, the pitch bend is normal, when I bend forward, the notes go up.
It's incomprehensible.

[KurtAgain]

  I noticed another strange thing - when I bend the pitch bend wheel forwards, the notes are lower. And when I bend the pitch bend wheel backwards, the notes go up. It used to be the other way around, a very strange fault.

Then the two external connections of the potentiometer were probably swapped during soldering or installation.

[werikas3210]

  No connections were changed during soldering, everything was done exactly as it should be. Before soldering, a photo was taken for accuracy and everything was soldered as it was.
It is not even possible to swap there, because the wires are too short to swap.
When the pitch bend broke, nothing had been soldered yet, and the operation was as reversed as it is now.

[KurtAgain]

Then the new potentiometer doesn't seem to be suitable, even if it has the same resistance value.

But according to the parts list and the service manual, the potentiometers for pitch bend and modulation should be of the exact same type. Maybe swapping the potentiometers is an option.

Your problem seems to occur sometimes. Here is a similar case: https://www.psrtutorial.com/forum/index.php?topic=53911.0
After several failed attempts, the solution in this case appears to have been to replace not just the potentiometer, but the entire circuit board to which the potentiometer is soldered.

Good luck!

[werikas3210]

   I have swapped the pitch bend potionciometer with the modulation potionciometer, unfortunately nothing has changed, the problem is the same.
I don't know how to change the whole circuit board, the Tyros4 pitch bend and modulation wheels are connected to the circuit board by 4 pins, and the circuit board is big because it has all the style buttons, accompaniment buttons and so on.
Thanks for the advice, but it would be complicated.

[mikf]

Werikas
I am with you, I don't understand why everyone keeps focussing on the wheel/potentiometer when you have already confirmed that the problem remains even when you use an expression pedal to operate pitch bend. I am pretty sure the potentiometer is bypassed when you use a pedal, because the pedal acts as a potentiometer and there is no connection between the pedal and the wheel to activate the internal potentiometer. So it cant be the potentiometer. 
Mike

[KurtAgain]

Werikas
I am with you, I don't understand why everyone keeps focussing on the wheel/potentiometer when you have already confirmed that the problem remains even when you use an expression pedal to operate pitch bend. I am pretty sure the potentiometer is bypassed when you use a pedal, because the pedal acts as a potentiometer and there is no connection between the pedal and the wheel to activate the internal potentiometer. So it cant be the potentiometer. 
Mike

Mike,
You're probably right. But that makes the error even more mysterious. I have only seen components on the signal path that usually last much longer than 10 years. Maybe it's just a configuration error that no one thinks about?
Kurt

[werikas3210]

   Hi, thank you to those who wanted to help me. Unfortunately, that's how I didn't handle pitch bend. Next, I play in the settings the number 0. I've been asking a lot about the problem, it seems like it just happened to me alone. Maybe someone else could help me with a pitch bend, I'll be really looking forward to the answer.

[ChrisH]

I was an electronic tech for many many years and to me Chris is correct ..the potentiometer that has been installed has a log curve not a linear curve ..you can see that because the range is correct 0 -127 but the centre point (wheel at rest) is 32 whereas it should be 64  ...  This is the correct linear pot to use https://syntaur.com/Part-3479-Potentiometer-10KB-rotary    It still sounds like the wrong pot was sold to you 

Chris