Yahoo Groups archive

Cgs synth

Index last updated: 2026-04-28 23:16 UTC

Thread

unwanted oscillations with CGS65 Tube VCA / timbral Gate

unwanted oscillations with CGS65 Tube VCA / timbral Gate

2007-07-17 by drsyncenstein

Hi,

I built two cgs65 from the rev. 1.1 pcb and with one vco
they function fine. But as soon as i connect a second vco
to the powersupply, the vca starts oscillating on it's own.
The audio of the vco is not even connected a that point
and the vca audio is not routed to the vca input.
Perhaps this has something to do with inadequate grounding?
Any suggestion how i could tackle this?

kind regards

Re: unwanted oscillations with CGS65 Tube VCA / timbral Gate

2007-07-17 by sasami@hotkey.net.au

It sounds like your PSU isn't up to the job. Try adding 100uF across each of
the power rails to earth.

Ken
Show quoted textHide quoted text
>Hi,
>
>I built two cgs65 from the rev. 1.1 pcb and with one vco
>they function fine. But as soon as i connect a second vco
>to the powersupply, the vca starts oscillating on it's own.
>The audio of the vco is not even connected a that point
>and the vca audio is not routed to the vca input.
>Perhaps this has something to do with inadequate grounding?
>Any suggestion how i could tackle this?
>
>kind regards
>
>
>
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>
>Yahoo! Groups Links
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.