OBERHEIM SYNTH

I'm not sure where TP12 is on the schematic. Check D703 and the two capacitors near it. This circuit generates the 5.6v. It is shown on page 12 of the schematic I have. Right in the center of the page. 

It could be that one of the 4051 chips is dragging down the 5.6v but more likely the problem is somewhere around the diode. The 5.6 volts is required for the CV to work properly. You are very close to finding the problem.
On Tuesday, May 6, 2014 8:01 PM, "zc40@..." <zc40@...> wrote:
  
  
>Hello, now I have another matrix unit that is correct, I've tried. or 801/3/4/9/10/11/12 and all is well ... The cpu also think it's good. 
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>I see a strange thing. TP 12. voltage is 4.5 V ... 5.6 should not be?
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>Thanks :)   
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