[sdiy] [AH] SH-101 VCA DC offset trimmer?

[Altitude]

Should work.

 

I went one step further and just added the pot and resistor to Guest's ba662
"clown" if you want to change it out . I suppose you could populate the
parts to trim it off but the BA662 should already be binned for offset

 

https://oshpark.com/shared_projects/QCnNP4oK

 

 

 

From: M V [mailto:mv_synths at hotmail.com] 
Sent: Sunday, October 25, 2015 12:29 PM
To: Altitude; 'synth-diy'
Cc: 'AH'
Subject: RE: [AH] SH-101 VCA DC offset trimmer?

 

Pulling up this old thread--so by adding this trimmer, you can effectively
remove the "pop" on the gate VCA on/off?

> From: altitude at optrand.com
> To: synth-diy at dropmix.xs4all.nl
> CC: analogue at hyperreal.org
> Date: Thu, 14 Jun 2012 07:47:38 -0400
> Subject: RE: [AH] SH-101 VCA DC offset trimmer?
> 
> It's a trimmer and a resistor that connects to pin 2 of the BA662A
> (R201)This is the same trick used to adjust the DC offset on the x0xb0x
with
> the BA6110. I use a 10M resistor and a 50KB Pot (thanks to B Castro).
> Works really well, you can get the "pop" down to nothing
> 
> http://midiot.net/blog/?p=3
> 
> It looks like Roland just went with "offset selected" op amps and never
> populated the trimmer
> 
> -----Original Message-----
> From: Doug Terrebonne [mailto:dougt55 at yahoo.com] 
> Sent: Thursday, June 14, 2012 2:50 AM
> To: synth-diy
> Cc: AH
> Subject: [AH] SH-101 VCA DC offset trimmer?
> 
> So for some reason Roland didn't include a VCA offset adjustment trimmer
in
> the SH-101. There is a location for one on the PCB though - 
> 
> 
> http://www.synthparts.com/sh101pcb1.jpg
> 
> When replacing the BA662A VCA it would be nice to have that adjustment.
> Anyone 
> ever try installing a 100K or so trimmer there? Looks like the proper
traces
> are 
> going to it...
> 
> Doug 
> synthparts.com
> 

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