Juno-106 bender pot

Hello all,
I’ve received a brand new bender pot, but the pitch range I get from it is around a minor third instead of a full octave. The pot alone, disassembled from the stick, can rotate on a wider angle and pitch plus or minus one octave.
So, I’m looking for a modification of the bender board in order to compensate for that.
Perhaps somebody here may know the trick ?
All the best,

Is it a pot that you purchased from Syntaur, or did you get it elsewhere?

I got it from Syntaur. Part #4952.

I just tested one of these pots from our stock in a Juno-106 bender, and it worked perfectly. It should turn the same number of degrees as the original.

Are you sure the DCO slider on the bender board is at maximum? When set fully forward, you should get an octave of bend up and down.

Also, when you tried the new pot, did it bend up the same amount as it bent downward? You have to have the bender lever in exactly the right orientation on the potentiometer shaft to get the same up and down bend range. If that is off, you might bend up a third, and down an octave, for example.

Thx for your help.
I confirm the dco slider is fully open when I test the bender range.
I get a tone down and a minor third up. I guess I can probably improve the center position of the pot a little bit.

Actually, if it works on your side, I don’t understand what’s wrong on my side. I’ll get further help from a tech this weekend.

Note : the pot alone, unmounted, can rotate something like +/-150°. And that way I get a full octave of pitch shift (in both directions). But when the pot is mounted, the bender stick only rotates +/-35°. And the pitch range is way lower (between a tone and a minor third).

I’ve grabbed a half working pot at a tech office. The measured resistance changes from 47 kOhm (centre position) to 0kOhm with a limited angle of just 35° (measured between two pins of the pot which are uselly connected to points 19 and 20 on the circuit board, but the pot isn’t connected).
As is, I believe the part number #4952 is not able to produce the necessary resistance with the limited angle of the bender.
Do you really get an octave up and down with it ?

We have a second customer who is having the same issue with this pot he got from us. So I am going to do some testing on this end and see what I can determine. What is perplexing is that we have sold a good number of these with no issues - so maybe there are some in the batch from the manufacturer that have the wrong taper…?

I will post back here soon, when I get this figured out. In the meantime, I’m sorry you are having trouble with this!

I’m still interested to know if you’ve found a workaround.
I’ve tried a bender pot from a JX-8P, and although it is a little bit better, I don’t have the full +/- one octave.

The pots we purchased turned out to have an incorrect taper. They were 100KB pots with a center tap, but the Juno bender pot has a much narrower range than a normal pot. On a normal pot, the taper extends over a 300 degree rotation range, and on the bender pot, this is all compressed to about 90 degrees. We have not been able to find a suitable part for this.

I’m surprised the JX-8P bender pot didn’t work. It is physically larger, but I would have guessed it has an identical taper. (It is 100KB also.)

Correction : it wasn’t from a jx8p : https://cgi.ebay.fr/ws/eBayISAPI.dll?ViewItem&item=264161401152

Do you have any plan to source pots with the correct taper ?

The pot you purchased from eBay (for the JD-800, etc) should be the identical part used in the Juno-106. So if it is also not working correctly, you may have trouble elsewhere. Are you getting the same bend range in both directions (up and down)?

Thanks for this pointer. Working on a Juno restoration project, and pulling my hair out looking for a suitable replacement pot. I’m going to give this one a shot.

Hi, Where can I find a Juno bender? Where’d you get yours? Syntaur doesn’t have it in stock.


Nevermind, I see you got yours from syntaur