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Discussion about the Korg PolySix synthesizer

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Calibration question(s)

Calibration question(s)

2003-01-29 by winzigus <at@terbrack.net>

Hi,

After bringing my dead Polysix back to life (Battery leakage,
faulty SSM 2056's) I decided to give him a completely new
calibration.

There are 2 points in the service manual which I have 
difficulties to understand:


- In "KLM-366 check and adjustment", point (3) "VCF RESONANCE
  adjustment":

  "Check CN05-7 with DVM and adjust to obtain 8.000V +/- 20mV"

What am I supposed to adjust ?

- In "KLM-367 adjustment", point (4) "PW/PWM check and adjustment":

  "...confirm there is a DC component of +0.2 ~ +0.5V"

My Polysix shows an offset of about 1.6V ... any ideas ?


Thanks in advance for any hints...


Regards, 

    Andreas.

Re: [PolySix] Calibration question(s)

2003-01-29 by J. Hausensteiner

Hi,

1) Adjust the RESONANCE knob for a 8.000V reading on the DVM.
   When trying to accomplish this you will notice that there
   are discrete steps in the value. Because our beloved analog
   baby is controlled *digitally* in reality. The analog
   control voltages (+/-5V) are digitized with 8 bits
   (256 steps), which gives a resolution of about 40mV.

2) This is misleading in the service manual. They do not mean
   the DC component but rather the the *minimum* value of the
   triangle waveform is supposed to be 0.2 ~ 0.5V. When you
   look at Fig. 4 this will be clear. The average value you
   will measure with a DVM will add half of the triangle wave
   amplitude, which results in 1.1 ~ 1.6V. So you are still
   within spec.


Cheers,

Johannes


PolySix@yahoogroups.com,Internet writes:
Show quoted textHide quoted text
>
>Hi,
>
>After bringing my dead Polysix back to life (Battery leakage,
>faulty SSM 2056's) I decided to give him a completely new
>calibration.
>
>There are 2 points in the service manual which I have 
>difficulties to understand:
>
>
>- In "KLM-366 check and adjustment", point (3) "VCF RESONANCE
>  adjustment":
>
>  "Check CN05-7 with DVM and adjust to obtain 8.000V +/- 20mV"
>
>What am I supposed to adjust ?
>
>- In "KLM-367 adjustment", point (4) "PW/PWM check and adjustment":
>
>  "...confirm there is a DC component of +0.2 ~ +0.5V"
>
>My Polysix shows an offset of about 1.6V ... any ideas ?
>
>
>Thanks in advance for any hints...
>
>
>Regards, 
>
>    Andreas.
>
>
>To unsubscribe from this group, send an email to:
>PolySix-unsubscribe@egroups.com
>
>PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ 
>
>
>

Re: Calibration question(s)

2003-01-30 by winzigus <at@terbrack.net>

Johannes,

Thanks for your detailed explantion. I initialy adjusted the
RESONANCE knob for 8V, unfortunately my max. resonance 
frequency is about 16KHz in step "VCF fo adjustment", not
19 ~ 24KHz.

The "minimum value of the waveform" is 1.6V (On the scope,
not DVM), maybe I have to check the D/A offset on the input
of the DeMux ...


Cheers,

   Andreas.


--- In PolySix@yahoogroups.com, "J. Hausensteiner" <jo.synth@c...> 
wrote:
> Hi,
> 
> 1) Adjust the RESONANCE knob for a 8.000V reading on the DVM.
>    When trying to accomplish this you will notice that there
>    are discrete steps in the value. Because our beloved analog
>    baby is controlled *digitally* in reality. The analog
>    control voltages (+/-5V) are digitized with 8 bits
>    (256 steps), which gives a resolution of about 40mV.
> 
> 2) This is misleading in the service manual. They do not mean
>    the DC component but rather the the *minimum* value of the
>    triangle waveform is supposed to be 0.2 ~ 0.5V. When you
>    look at Fig. 4 this will be clear. The average value you
>    will measure with a DVM will add half of the triangle wave
>    amplitude, which results in 1.1 ~ 1.6V. So you are still
>    within spec.
> 
> 
> Cheers,
> 
> Johannes
> 
> 
> PolySix@yahoogroups.com,Internet writes:
> >
> >Hi,
> >
> >After bringing my dead Polysix back to life (Battery leakage,
> >faulty SSM 2056's) I decided to give him a completely new
> >calibration.
> >
> >There are 2 points in the service manual which I have 
> >difficulties to understand:
> >
> >
> >- In "KLM-366 check and adjustment", point (3) "VCF RESONANCE
> >  adjustment":
> >
> >  "Check CN05-7 with DVM and adjust to obtain 8.000V +/- 20mV"
> >
> >What am I supposed to adjust ?
> >
> >- In "KLM-367 adjustment", point (4) "PW/PWM check and adjustment":
> >
> >  "...confirm there is a DC component of +0.2 ~ +0.5V"
> >
> >My Polysix shows an offset of about 1.6V ... any ideas ?
> >
> >
> >Thanks in advance for any hints...
> >
> >
> >Regards, 
> >
> >    Andreas.
> >
> >
> >To unsubscribe from this group, send an email to:
> >PolySix-unsubscribe@egroups.com
> >
> >PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> >
> >Your use of Yahoo! Groups is subject to 
http://docs.yahoo.com/info/terms/ 
Show quoted textHide quoted text
> >
> >
> >

Re: Calibration question(s)

2003-01-30 by winzigus <at@terbrack.net>

Sorry, I had a typo in my original question, I am still wondering
what to adjust to get 0V at CN05-7 (_not_ the 8V on CN05-11)

If I adjust VCF CUTOFF to 0V, my max res freq is about 16KHz,
(as mentioned below) VCF RESONANCE has no effect on CN05-7.


Thanks again,

Andreas.  

--- In PolySix@yahoogroups.com, "winzigus <at@t...>" <at@t...> wrote:
> 
> Johannes,
> 
> Thanks for your detailed explantion. I initialy adjusted the
> RESONANCE knob for 8V, unfortunately my max. resonance 
> frequency is about 16KHz in step "VCF fo adjustment", not
> 19 ~ 24KHz.
> 
> The "minimum value of the waveform" is 1.6V (On the scope,
> not DVM), maybe I have to check the D/A offset on the input
> of the DeMux ...
> 
> 
> Cheers,
> 
>    Andreas.
> 
> 
> --- In PolySix@yahoogroups.com, "J. Hausensteiner" <jo.synth@c...> 
> wrote:
> > Hi,
> > 
> > 1) Adjust the RESONANCE knob for a 8.000V reading on the DVM.
> >    When trying to accomplish this you will notice that there
> >    are discrete steps in the value. Because our beloved analog
> >    baby is controlled *digitally* in reality. The analog
> >    control voltages (+/-5V) are digitized with 8 bits
> >    (256 steps), which gives a resolution of about 40mV.
> > 
> > 2) This is misleading in the service manual. They do not mean
> >    the DC component but rather the the *minimum* value of the
> >    triangle waveform is supposed to be 0.2 ~ 0.5V. When you
> >    look at Fig. 4 this will be clear. The average value you
> >    will measure with a DVM will add half of the triangle wave
> >    amplitude, which results in 1.1 ~ 1.6V. So you are still
> >    within spec.
> > 
> > 
> > Cheers,
> > 
> > Johannes
> > 
> > 
> > PolySix@yahoogroups.com,Internet writes:
> > >
> > >Hi,
> > >
> > >After bringing my dead Polysix back to life (Battery leakage,
> > >faulty SSM 2056's) I decided to give him a completely new
> > >calibration.
> > >
> > >There are 2 points in the service manual which I have 
> > >difficulties to understand:
> > >
> > >
> > >- In "KLM-366 check and adjustment", point (3) "VCF RESONANCE
> > >  adjustment":
> > >
> > >  "Check CN05-7 with DVM and adjust to obtain 8.000V +/- 20mV"
> > >
> > >What am I supposed to adjust ?
> > >
> > >- In "KLM-367 adjustment", point (4) "PW/PWM check and 
adjustment":
Show quoted textHide quoted text
> > >
> > >  "...confirm there is a DC component of +0.2 ~ +0.5V"
> > >
> > >My Polysix shows an offset of about 1.6V ... any ideas ?
> > >
> > >
> > >Thanks in advance for any hints...
> > >
> > >
> > >Regards, 
> > >
> > >    Andreas.
> > >
> > >
> > >To unsubscribe from this group, send an email to:
> > >PolySix-unsubscribe@egroups.com
> > >
> > >PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> > >
> > >Your use of Yahoo! Groups is subject to 
> http://docs.yahoo.com/info/terms/ 
> > >
> > >
> > >

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