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Portamento circuit DIY

Portamento circuit DIY

2009-02-21 by mrjdevries

Hey all.

I need to build a simple portamento circuit for one of my CV'd up 
synths.. just wanting to know if anyone has some ideas? (It's 
1V/octave)

I found this one on the net, and it seems simple enough? Any 
pointers / Tips / advice would be greatly appreciated.

>      
>      
>                                                                     
      
>        +----------------------------------------+-------
+                 
>        | -                                      | -     
|                 
>        +--|\          330         1-10 Meg      +--|\   
|                 
>           | /-------/\/\/\/----+-/\/\/\/\-----+    | /--+-----> 
output    
>      >----|/                   |    ^         +----
|/                     
>          +                     |    |         |   
+                       
>      input                     +----+         
|                           
>                                               
|                           
>                               "GLIDE"       ----- C = 1 - 10 
uf           
>                                             ----- non-
polarized           
>                                               
|                           
>            op-amp = TL082 etc.                
|                           
>                                             -----
                         
>                                              ---
                          
>                                               -
                           
>                                                                     
      
>      Notice that this circuit will produce linear glide like the 
Minimoog 
>      (rather than exponential like just about everything else). 
Exponential 
>      glide can be achieved by getting rid of the op-amp on the left 
and 
>      sticking the input right into the pot.
>      

Regards
Mike

Re: Portamento circuit DIY

2009-02-21 by mrjdevries

Ok, that ASCII schematic didn't come out right.

>      
>      
>                                                                     
>        +----------------------------------------+-------+
>        | -                                      | -     |
>        +--|\          330         1-10 Meg      +--|\   | 
>           | /-------/\/\/\/----+-/\/\/\/\-----+    | /--+-->output
>      >----|/                   |    ^         +----|/ 
>          +                     |    |         |   + 
>      input                     +----+         | 
>                                               |
>                               "GLIDE"       ----- C = 1 - 10 uf
>                                             ----- non-polarized
>                                               | 
>            op-amp = TL082 etc.                | 
>                                             ----- 
>                                              --- 
>                                               -  
>                                                                     
"Notice that this circuit will produce linear glide like the Minimoog
(rather than exponential like just about everything else). 
Exponential glide can be achieved by getting rid of the op-amp on the 
left and sticking the input right into the pot."

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