OBERHEIM SYNTH

I'm guessing you injected a signal into the DAC output and got a good loud signal at the output. Good job verifying the analog half of the circuit!!!
 
Does the DAC have digital inputs that are working? Do you have 500khz coming out of U607B? U617C toggles the DAC write line. The 82C54 timers U610 - U612 provide the initial frequencies for the voice chips. Are they running? There should be 8 bits on the data side of these timers. This data comes from the CPU.
 
 
On Tuesday, April 22, 2014 7:05 AM, "zc40@hotmail.com" <zc40@...> wrote:
  
  
>Hello, take long to respond. 
>  I've been looking, I saw how it works this part and is in good condition, For the voices, no sound. 
>  I have seen all of this is controlled by CV, I also did a test, remove the DAC (AM6012), and turned, and was loud. thus, I think the voices can be fine. I think that the problem may be within the control.  
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