> 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