Doepfer

--- In Doepfer_a100@yahoogroups.com, <yahoo@...> wrote:
>
> > Hi all
> >
> > I have two of these modules (bought 6 weeks ago) and only just
> > got round to checking the second VCA of the second module.
> > There's a fault: It doesn't shut down fully. With both the CV and
> > gain controls at zero I can still here an oscillator patched
> > directly into it. My other 3 VCAs all fully shut off the input at
> > this setting as expected.
> >
> > Is this something that I can fix by adjusting a pot somewhere or
> > do I need to think about returning it as faulty?
> >
> > Thanks
> >
> > Rich
> 
> There is nothing to trim on this module. In the first series of the module
> (manufactured until ~ September 2008) this behaviour was discovered now and
> then due to tolerances of the dual VCA circuit (CEM3360). From September
> 2008 the value of two resistors have been changed to avoid that (R10 and R24
> = 220k instead of 270k). If you are a bit familiar with electronics please
> take a look at your module: R24 is the resistor at the bottom edge of the pc
> board (below the switch). If the value is 270k (red-violet-yellow) it's from
> the first series. If it's 220k (red-red-yellow) it's from the second series.
> I'd recommend to return the module for modification (or to replace the 270k
> resistors by 220k if you dare to do that and you have these values
> available) or replacement of the CEM3360.
> 
> Best wishes
> Dieter Doepfer
>

Thanks for the quick reply Dieter, I'll check resistor values when I get home.

Is it true that this would just affect the lower VCA on the module while the upper one works correctly?

Thanks

Rich