KVR Audio

MaxSynths · Post by **MaxSynths** » Sat Oct 05, 2013 11:31 am

This is the potentiometer of the pitch bend wheel of a Fatar Studio 900 master keyboard. It's broken since it started to send out random values without touching it. The problem is that I have no idea where to get a similar pot... it has 4 contacts (the soldering points are those marked in red).

I've tried to contact Fatar (it seems they have something similar in their catalog, but I'm not sure if it works only for the recent models and I'm still waiting for a reply).

In case of a negative reply does anyone know if something like this exists in the market? I've tried to search the web with no lucky...

Hink · Post by **Hink** » Sat Oct 05, 2013 5:47 pm

what's the value of the pot?

Have you tried http://www.mouser.com/

WOK · Post by **WOK** » Sat Oct 05, 2013 6:00 pm

Can you measure with an ohmmeter what the 4th contact is doing? Maybe it's just connceted to the shielding....

WOK · Post by **WOK** » Sun Oct 06, 2013 1:51 pm

http://www.syntaur.com/3713.html

http://de.mouser.com/ProductDetail/ALPS ... o5YXp14w==

http://www.ctech-ind.com/index.php/prod ... meter.html

http://commons.wikimedia.org/wiki/File: ... ometer.svg

MaxSynths · Post by **MaxSynths** » Fri Oct 11, 2013 2:27 pm

Hey guys, first of all sorry for the delay (I've been busy with the warez releases of my software lately

)

@Hink: The value of the pot is 10K

@WOK: I don't have a volt meter around, by the way I've just opened the pot and this is how it looks inside:

Wok wrote:
http://www.syntaur.com/3713.html

http://de.mouser.com/ProductDetail/ALPS ... o5YXp14w==

http://www.ctech-ind.com/index.php/prod ... meter.html

http://commons.wikimedia.org/wiki/File: ... ometer.svg

These seems fine... I only need to know what the 4th contact is doing...

Max

WOK · Post by **WOK** » Fri Oct 11, 2013 9:04 pm

This seems to be a center tap poti - resistance of the (slider's) middle pin is not only measured to it's left and right neighbours but also to a 4th connector at the middle of the surface. This was used in old radios volume knobs to have a second value if the knob is less the 1/3 or 1/2 to control loudness.
Maybe Fatar has build an unlinear pitch bend wheel with more effect to the end.
Try a 10k center tap poti of my links, if there is no one mechanical matching, you can try a normal one and connect the wire of the extra pin to the left or right pin with a 10k resistor; it should work linear then.

MaxSynths · Post by **MaxSynths** » Sun Oct 27, 2013 8:35 pm

I'm waiting for the pot, in the meantime I post this scheme of the PB/MW:

I'm a bit confused... The PB and MW are sharing two cables, the blue and pink (the pink is attached on the 4th pin on both pots).

antto · Post by **antto** » Mon Oct 28, 2013 9:23 am

i'd say pink is ground, blue would be +5V or so..

[HELP] Where can I find a potentiometer like this?