hello florian,

many thanks for the great explanation :-)

best wishes

ingo



--- In Doepfer_a100@yahoogroups.com , Florian Anwander
<Florian.Anwander@c...> wrote:

> Hi Ingo
>
> > is it a simple modification soldering is not one
> > of my biggest strengths ;-)
> Yes, quite simple.
>
> From the center connector of the poti (=slider) a resistor leads

to the

> mixing point. The less the resistor the wider is the range of the

poti.

>
> As far as I remember the value is 1 Megaohm for the coarse.
> You do not have to remove the existing resistor. Simply add a

resistor

> with lower value parallel to the existing resistor.
>
> I added an 220kOhm resistor for the coarse tune. The value for fine

tune

> I do not remember at the moment.
>
>
>
>
>
>
> Further explanations:
>
>
> PP=Poti
> Ra=existing Resistor
> Rb=new Resistor
>
>
> Before:
>
> ----PP
> PP
> PP<----RaRaRa-----
> PP
> ----PP
>
>
> After:
>
> ----PP
> PP
> PP<--+-RaRaRa-+---
> PP | |
> ----PP +-RbRbRb-+
>
>
>
> R'a and R'b appear electrical like one Resistor R'eff.
>
>
> The new value can be determined by the following formula:
>
> R'eff = R'a * R'b / (R'a + R'b)
>
> Where is:
> R'a is the existing resistor
> R'b is the new add on resistor
> R'eff is the resulting value
>
>
>
> Example:
> Old resistor=1Megohm
> New resistor=1Megohm
>
> 1*1/(1+1) = 1/2 = 0,5
>
> So the resulting value is 0,5Megaohm. This would double the range

of the

> poti.
>
>
> Florian