[sdiy] TH XR2206 VCO tune pot

[Derek Holzer]

Hi Scott,

thanks for your reply. I did think of this, but since the range of 
another pot in the schemo is restricted by following it with a larger 
resistor, rather than putting resistors between V+/V- and the pot, I 
thought that I would try to understand how that worked.

best!
Derek

Scott Gravenhorst wrote:

> You can restrict the range of the pot this way:
> 
>      v+
>      |
>      |
>      Ra
>      |                                            
>      |                                       
>      P
>      O<----- ...
>      T
>      |
>      |
>      Rb
>      |
>      |                                  
>      V-     
> 
> Where POT is the original tuning pot and Ra and Rb are resistors you will add.  The
> values of these resistors will have to be trimmed or calculated by you.  If Ra and Rb
> are the same resistance as the pot, then the new range will begin at about a third of
> where it was without Ra and Rb and it will end about 1/3 before it gets to the end.  I
> can't guess what frequencies this will give...  Ra and Rb can also be trimmers so that
> you can adjust the exact range you get.

-- 
::: derek holzer ::: http://blog.myspace.com/macumbista ::: 
http://www.vimeo.com/macumbista :::
---Oblique Strategy # 101:
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