Vintage Synth Repair

I have a D-5 with a trashed pitchbend potentiometer - it literally  
fell apart when I removed it.   The modulation sensor still works  
fine, so I don't want to go to the extreme of replacing the entire  
assembly (assuming it's even still available) unless absolutely  
necessary.

It's a 16mm 100K pot and I assume it's linear given the application  
(?).  What's throwing me is, it has four terminals - the three normal  
ones, plus one on the other side which I assume is a ground.

I've looked at Jaycar and Dick Smith but they don't have any 4- 
terminal pots like this, and I'm concerned what they have would have  
too stiff an action for a pitchbender anyway.

Any suggestions?

Many thanks,
Lindsay

I have some 4 lead pots for peavey amps. The 4th lead goes nowhere. Why would peavey would buy this ALPS pot for amp when the 3 leads for fine??

Scott  Frye
AudioFixation
Consumer / Pro Audio Repair
Southern VT 

"Resistance is futile but.....
Impedance is much more complex"

Hi,
Typically the 4th lead is a center connection half way
between the pot full clockwise and full counter clockwise.
The idea is that you could connect this to a ground or voltage
and it would be an absolute center point in the pot's rotation.

In the case of Peavey, I believe they used them for circuit board 
mounting stability so that when you secured the pot to the panel
the circuit board was also secure.

Hope this helps.
GD



--- In vintagesynthrepair@yahoogroups.com, scott frye 
<painintheamp@...> wrote:
>
> I have some 4 lead pots for peavey amps. The 4th lead goes 
nowhere. Why would peavey would buy this ALPS pot for amp when the 3 
leads for fine??

> 
> Scott  Frye
> AudioFixation
> Consumer / Pro Audio Repair
> Southern VT 
> 
> "Resistance is futile but.....
> Impedance is much more complex"
>

all 4 legs of this pot go "somewhere"  according to D5 SCHEMATIC.
the fourth leg is a tap, we have replacements, where do you want it  
sent?
please dont say Canada, Russ
actually i think we can surface-mail to canada wihout too much hassle.

On Feb 11, 2009, at 5:27 PM, Pascur wrote:

> I have a D-5 with a trashed pitchbend potentiometer - it literally
> fell apart when I removed it.   The modulation sensor still works
> fine, so I don't want to go to the extreme of replacing the entire
> assembly (assuming it's even still available) unless absolutely
> necessary.
>
> It's a 16mm 100K pot and I assume it's linear given the application
> (?).  What's throwing me is, it has four terminals - the three normal
> ones, plus one on the other side which I assume is a ground.
>
> I've looked at Jaycar and Dick Smith but they don't have any 4-
> terminal pots like this, and I'm concerned what they have would have
> too stiff an action for a pitchbender anyway.
>
> Any suggestions?
>
> Many thanks,
> Lindsay
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>