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Need some help with the Wavemultiplier CGS29 REV 2

Need some help with the Wavemultiplier CGS29 REV 2

2006-01-02 by fonik2000

Hi all,

I am new to this forum and I am relatively new to SDIY, too. I
started building a modular synth about one year ago, knowing nothing
at all. The first module I ever built was the Psycho LFO – a great,
easy to build and very effective circuit.

Now I run into some problems with the Wavemultiplier CGS29 REV 2. It
seems to work but with a very, very low output. The PWM doesn´t work
at all.
So I checked all traces and values against the schematic and found
that the schematic differs from the pcb layout?!.
On the schematic pin1 of IC5 is connected to pin5 of IC4 (positive
input) and pin1 of IC4 is connected to pin6 of IC4 (negative input),
while on the pcb layout pins 5 and 6 of IC4 are interchanged. Might
this be the cause of the circuit malfunction?

Any comment is appreciated for I am willing to learn more about these
things.

Thank you all in advance

Matthias Herrmann
Germany

Re: Need some help with the Wavemultiplier CGS29 REV 2

2006-01-02 by sasami@hotkey.net.au

The board is correct. The board has been tested and works without any problems.

You will have either a bad solder joint, or a mis-read component, I suspect,
or you are running the internal VCA too quietly. The FOLDS CV input or knob
need to be increased.

Ken
Show quoted textHide quoted text
>Hi all,
>
>I am new to this forum and I am relatively new to SDIY, too. I
>started building a modular synth about one year ago, knowing nothing
>at all. The first module I ever built was the Psycho LFO – a great,
>easy to build and very effective circuit.
>
>Now I run into some problems with the Wavemultiplier CGS29 REV 2. It
>seems to work but with a very, very low output. The PWM doesn´t work
>at all.
>So I checked all traces and values against the schematic and found
>that the schematic differs from the pcb layout?!.
>On the schematic pin1 of IC5 is connected to pin5 of IC4 (positive
>input) and pin1 of IC4 is connected to pin6 of IC4 (negative input),
>while on the pcb layout pins 5 and 6 of IC4 are interchanged. Might
>this be the cause of the circuit malfunction?
>
>Any comment is appreciated for I am willing to learn more about these
>things.
>
>Thank you all in advance
>
>Matthias Herrmann
>Germany
>
>
>
>
>
>
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>
>Yahoo! Groups Links
>
>
>
>
>
>
>
_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: Need some help with the Wavemultiplier CGS29 REV 2

2006-01-03 by fonik2000

hi ken,

thank yo very much for your fast and kind reply. i just wanted to be
sure. now i will have to do some homework...;)

matthias
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, sasami@h... wrote:
>
> The board is correct. The board has been tested and works without
any problems.
>
> You will have either a bad solder joint, or a mis-read component, I
suspect,
> or you are running the internal VCA too quietly. The FOLDS CV input
or knob
> need to be increased.
>
> Ken

follow up: Need some help with the Wavemultiplier CGS29 REV 2

2006-01-13 by Matthias Herrmann

hi ken,

i´ve done my homework yesterday and yes, there was a slack joint i
missed two times... - silly me;(
one touch with the hot iron and voila: it works - no, it rocks!
a great circuit that "multiplies" the cababilities in large amounts:)

thanks ken!
matthias herrmann
Show quoted textHide quoted text
--- In cgs_synth@yahoogroups.com, "fonik2000" <fonik@w...> wrote:
>
> hi ken,
>
> thank yo very much for your fast and kind reply. i just wanted to
be
> sure. now i will have to do some homework...;)
>
> matthias
>
> --- In cgs_synth@yahoogroups.com, sasami@h... wrote:
> >
> > The board is correct. The board has been tested and works without
> any problems.
> >
> > You will have either a bad solder joint, or a mis-read component,
I
> suspect,
> > or you are running the internal VCA too quietly. The FOLDS CV
input
> or knob
> > need to be increased.
> >
> > Ken
>

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