Discussion about the Korg PolySix synthesizer

So after I fixed some grounding issue yesterday, it seems that my Polysix doesn't recall the patches: they're all initialised to random, not-too-usable sounds.

Where should I look at testing on the boards (KLM-367 at least, correct?). Any particular chips + traces?

Before my fixes yesterday, I did manage to briefly recall my own patches internally, so I know the battery is good, the memory should be good and I'd tend to think about some bad trace somewhere instead.

Thoughts on how to narrow it down?

If you have a scope, check every signal that connects to the RAM chip.
If you only have a meter, you can check resistance from the RAM signals 
to other chips that they hook to.   If your battery is socketed, remove it,
and do the ohmmeter checks with the synth powered down of course.
Measuring resistance with a DMM on signals that have voltage on 
them doesn't work.

Bob

--------------------------------------------
On Fri, 5/12/17, josh.nursing@gmail.com [PolySix] <PolySix@yahoogroups.com> wrote:

 Subject: [PolySix] Patch Recall issue
 To: PolySix@yahoogroups.com
 Date: Friday, May 12, 2017, 1:08 PM
 
 
  
 
 
 
   
 
 
     
       
       
       So after I fixed some grounding issue
 yesterday, it seems that my Polysix doesn't recall the
 patches: they're all initialised to random,
 not-too-usable sounds.
 Where
 should I look at testing on the boards (KLM-367 at least,
 correct?). Any particular chips + traces?
 Before my fixes yesterday, I did manage
 to briefly recall my own patches internally, so I know the
 battery is good, the memory should be good and I'd tend
 to think about some bad trace somewhere instead.
 Thoughts on how to narrow it down?
 
     
      
 
     
     
 
 
 
 #yiv8329322592 #yiv8329322592 --