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Subject: Re: [PolySix] Calibration question(s)

From: "J. Hausensteiner" <jo.synth@crossnet.at>
Date: 2003-01-29

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.
>
>
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