OBERHEIM SYNTH

Do you have an actual audio signal through the potentiometer? If so work your way towards the output jack. U1, C4, etc. If not you can go back to U24 then the 4053 inputs and finally the output of the voice chips. Hopefully you will find audio somewhere along this path. Sorry to start in the middle.

You seem to have a good knowledge of testing and you have great test gear. Too bad we only have this barely readable print here in the files area. My old eyes are not very good with fuzzy schematics....
On Sunday, April 20, 2014 10:25 AM, "zc40@..." <zc40@...> wrote:
  
  
>Hello Narfman. 
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>I tried regulators, 7912 & 7812. They look good, no voltage drop. The +5 & -5, also looks good. 
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>I have an oscilloscope Tetronix & genreador signal and a voltmeter. evidence to go by. 
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>The potentiometer output is fine. 
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>From where you think you can do the first step?  
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