Discussion about the Korg PolySix synthesizer

The gate signals should turn on as the notes are assigned.   There are two chips that drive those, 
IIRC.    maybe 40174's?   

Do the LED's come on on the voice board as you play keys?

If so, then the gate (digital) signals are working, and you would look at analog signals in the 
VCA or VCF area.

Bob

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On Tue, 7/21/15, remodulator@yahoo.com.au [PolySix] <PolySix@yahoogroups.com> wrote:

 Subject: [PolySix] Polysix key assigner testing....
 To: PolySix@yahoogroups.com
 Date: Tuesday, July 21, 2015, 10:41 AM
 
 
  
 
 
 
   
 
 
     
       
       
       I am working on a Polysix that
 refuses to play a note.  and hoping somebody has a good
 troubleshooting process. The CPU board seems to be working
 OK, with no evidence of acid damage. A lithium CR2032
 battery mod installed. Power supply voltages check out, All
 the front panel LEDs seem to work properly. Tape enable
 switch is off. I set the board to manual mode and
 preset reasonable settings but I cant get the board to make
 a sound. There is activity on the KLM366B including some
 signals coming from the 8049-217 key assigner MPU. 
  It would be very
 helpful to know if there is a signal that is latched or
 triggered when a key is pressed. I can see pulses scanning
 the key matrix and when a key is pressed, some signals
 returning to the MPU, but what does the MPU do when a key is
 pressed?  Is there
 a simple and safe way to manually trigger the
 VCOs...? Any and
 all suggestions or advice gratefully accepted...!
 
     
      
 
     
     
 
 
 
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