Archive of the former Yahoo!Groups mailing list: Discussion about the Korg PolySix synthesizer

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Subject: RE: [PolySix] Re: Polysix restoration: LEDs

From: "backshall1" <backshall1@bellsouth.net>
Date: 2013-01-30

If you are talking about getting the correct LEDs to light up during DAC
calibration on the clone boards, no I don't think anybody has a guaranteed
way to make this work. The last time I calibrated one of these, I ended up
just setting VR6 and VR7 by watching the DAC output on an oscilloscope and
listening to the factory sounds. I think I've heard those patches enough
that I can tell if they sound incorrect. I watched the scope to make sure
the DAC output was symmetrical in the negative and positive directions when
a knob was moved from 0 to 10, and showed 0V when the knob was in its center
position.



I tried substituting a 4560 instead of TL072 for IC27, as per the original
boards, but that just made things worse.



Don B.



_____

From: PolySix@yahoogroups.com [mailto:PolySix@yahoogroups.com] On Behalf Of
Boddington
Sent: Tuesday, January 29, 2013 5:38 PM
To: PolySix@yahoogroups.com
Subject: [PolySix] Re: Polysix restoration: LEDs, Sub-Osc LFO issues.





Hey there -

Did the DAC issue everr get resolved? I', still stuck in this part of the
calibration as well. Any help would be great!





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