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Moog Modular 901a/b Driver and Osc question.

Moog Modular 901a/b Driver and Osc question.

2009-07-26 by Quazimodo

Hi everyone,

I have a question about the early Moog Modular 901a/b Oscillator Controller/Driver.

The cicuit diagram can be found here at the Moog Archives here:
http://www.moogarchives.com/  (click 'modules' on the left)

Looking at the cct diagram connector pin-out, there are 'A' 'B' and CONTROL NODE pins.

Now, the 901b Oscillator connector pin-out has an 'A' 'B' and 'C' - would the 'C' interface with the CONTROL NODE pin on the Controller/Driver cct?

Also, the Controller/Driver connector shows the 'Width of pulse waveform' circuit between pins 6 and 13 - but that seems to be it - pins 6 and 13 do not appear anywhere in the circuit... where does this pulse width circuit interface to..?

I hope someone can shed some light on these mysteries.

Thanks in advance,
Tom

Re: [vintagesynthrepair] Moog Modular 901a/b Driver and Osc question.

2009-07-26 by Terje Winther

Pin 6 of the driver, which controls the pulse width, goes to pin 6 of the osc, which goes directly to the pulse section.
This also happens to be the "c" connection designation.
"Control Node" is for external control, for example through a CP module routing the keyboard voltage to the VCOs.

tw.

Den 26. juli. 2009 kl. 21.39 skrev Quazimodo:

Hi everyone,

I have a question about the early Moog Modular 901a/b Oscillator Controller/Driver.

The cicuit diagram can be found here at the Moog Archives here:
http://www.moogarchives.com/ (click 'modules' on the left)

Looking at the cct diagram connector pin-out, there are 'A' 'B' and CONTROL NODE pins.

Now, the 901b Oscillator connector pin-out has an 'A' 'B' and 'C' - would the 'C' interface with the CONTROL NODE pin on the Controller/Driver cct?

Also, the Controller/Driver connector shows the 'Width of pulse waveform' circuit between pins 6 and 13 - but that seems to be it - pins 6 and 13 do not appear anywhere in the circuit... where does this pulse width circuit interface to..?

I hope someone can shed some light on these mysteries.

Thanks in advance,
Tom



Re: Moog Modular 901a/b Driver and Osc question.

2009-07-28 by Quazimodo

Many thanks for the reply Terje,

I can now see that also pin 13 is 'ground' so I understand how it interfaces.

Thanks again
Tom


--- In vintagesynthrepair@yahoogroups.com, Terje Winther <terje.winther@...> wrote:
Show quoted textHide quoted text
>
> Pin 6 of the driver, which controls the pulse width, goes to pin 6 of  
> the osc, which goes directly to the pulse section.
> This also happens to be the "c" connection designation.
> "Control Node" is for external control, for example through a CP  
> module routing the keyboard voltage to the VCOs.
> 
> tw.
> 
> Den 26. juli. 2009 kl. 21.39 skrev Quazimodo:
> 
> > Hi everyone,
> >
> > I have a question about the early Moog Modular 901a/b Oscillator  
> > Controller/Driver.
> >
> > The cicuit diagram can be found here at the Moog Archives here:
> > http://www.moogarchives.com/ (click 'modules' on the left)
> >
> > Looking at the cct diagram connector pin-out, there are 'A' 'B' and  
> > CONTROL NODE pins.
> >
> > Now, the 901b Oscillator connector pin-out has an 'A' 'B' and 'C' -  
> > would the 'C' interface with the CONTROL NODE pin on the Controller/ 
> > Driver cct?
> >
> > Also, the Controller/Driver connector shows the 'Width of pulse  
> > waveform' circuit between pins 6 and 13 - but that seems to be it -  
> > pins 6 and 13 do not appear anywhere in the circuit... where does  
> > this pulse width circuit interface to..?
> >
> > I hope someone can shed some light on these mysteries.
> >
> > Thanks in advance,
> > Tom
> >
> >
> > 
> 
> Terje Winther
> terje.winther@...
> http://www.wintherstormer.no/
>

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