[sdiy] VCO bleed through to other modules

[Ian Fritz]

At 07:16 PM 3/23/06, Paul Perry wrote:

>But I suspect the original problem, is crying out for
>220 ohm resistors in series with the power supply
>and decoupling caps for at least the VCO module..

Sounds maybe even worse than that.  My guess is a gross wiring error -- 
like not understanding how to hook up the common, ground and sense 
terminals.  But I don't know that perticular supply.

BTW, I try to avoid the series R + cap decoupling scheme.  It makes your 
power supply to the module "soft".  I remember one of the audio gurus 
screaming about this a while back.  I try to keep a "star" distribution 
system with lots of ferrite beads and, of course, subregulation for 
critical voltages.

   Ian



>paul perry melbourne australia
>----- Original Message -----
>From: "Ian Fritz" <ijfritz at earthlink.net>
>To: "Paul Perry" <pfperry at melbpc.org.au>; <synth-diy at dropmix.xs4all.nl>
>Sent: Friday, March 24, 2006 1:03 PM
>Subject: Re: [sdiy] VCO bleed through to other modules
>
>
> > Hmmm...wouldn't that work only if the jack were isolated, i.e., not
> > connected to a grounded panel?
> >
> >
> > At 06:38 PM 3/23/06, Paul Perry wrote:
> > >A possible reason why this helps, is because (if the two wires are
> > >tied together) the radiated field from the current cancels out
> > >(opposite direction along the two wires).
> > >
> > >paul perry melbourne australia
> > >