Discussion about the Korg PolySix synthesizer

Hello list.

I'm working on a broken KLM367 where i so far have put new logic
on IC 30, 31, 24, 26, 28, 29, 34, 35.

When i test the reset circuit with a 56kohm dummy all the leds light up but won't change when i adjust VR1. It only changes when i remove the dummy and adjust on VR1.?

The polysix makes sound and all pots works except all the switches on KLM 369 dont work. The sound it self sounds like its being modulated by an fast lfo that wont go away and it's not from the polysix lfo! bad A/D?.

Ok, any light on this matter is help full!

/Robert Leiner

Hi Robert,

Are you repairing a board that has been acid damaged? That is an awful lot
of silicon to be changing in one go! If you can¹t set up the reset circuit
properly and just get a permanent active low in test mode then try replacing
zener diode D2. As far the switches being in trouble do check the operation
of the quad latches IC28/29/34/35. Moreover make sure there is a pulse train
at the clock pin (5). If this board has had an acid spill then the lines
back to P24/25 on the CPU are prone to becoming disconnected as they run
under where the battery used to be!

Cheers,
Andy  




On 23/02/2011 17:57, "robobob66" <robertleiner@gmail.com> wrote:

>  
>  
>  
>    
> 
> Hello list.
> 
> I'm working on a broken KLM367 where i so far have put new logic
> on IC 30, 31, 24, 26, 28, 29, 34, 35.
> 
> When i test the reset circuit with a 56kohm dummy all the leds light up but
> won't change when i adjust VR1. It only changes when i remove the dummy and
> adjust on VR1.?
> 
> The polysix makes sound and all pots works except all the switches on KLM 369
> dont work. The sound it self sounds like its being modulated by an fast lfo
> that wont go away and it's not from the polysix lfo! bad A/D?.
> 
> Ok, any light on this matter is help full!
> 
> /Robert Leiner
> 
>  



[Non-text portions of this message have been removed]

So, I have three KLM-367 clone boards finished and working well. Now onto calibration...

[Back story you can skip]  I decided to assemble them and get them all working adequately before I started the calibrating stage. Now, this isn't the first time I've done a calibration on the new boards. I tried a partial calibration few months back when I got my first board up and running, but part way through I decided to stop and wait until I had all the boards done. The process was, how shall I put this politely, infuriating(!) as the instructions were vague at best with things lost in translation and perhaps a few assumptions made by the manual author on the tech/person doing the calibrations and their experience/knowledge. 

Now that I'm heading back into calibration mode, I was wondering if any of you guys have a plain English interpretation of the instructions. Something a little more thorough, and less... Engrish. 

One of the first things I'm having trouble figuring out is what the heck is DC Click Noise (Step 7)? And where the heck do I read this from? The Main out? A test point? If so, which one? How important is this step?

I'm just starting out so there might be a bunch more questions down the line. Figured I'd start with this one.

Thanks in advance. And thanks again to Andy for helping me get through the assembly and subsequent troubleshooting. You da man!

Arturo....

============================================ 
Arturo Brisindi

[Musics]

mydadvsyours.com  |  soundcloud.com/arturo00

 

[Studios]

galleryrecording.weebly.com  |  arturo00.weebly.com

 		 	   		  

[Non-text portions of this message have been removed]

Hi Arturo,

What they mean by this is that they only want a certain amount of DC to be
present at the audio line out jack when you switch the P6 on. This is the
Œthump¹ you hear when you hit the mains switch. In this case they are
advising that not more than 6vdc peak ­ peak is present. You¹ll have to
measure a transient like that with a storage scope, unless anyone else out
there has a better idea. I shouldn¹t get too hung up about it unless your
speakers pop out and start rolling around on the floor.

Cheers,
Andy


On 24/02/2011 03:05, "Arturo B" <arturo00@hotmail.com> wrote:

>  
>  
>  
>    
> 
> 
> So, I have three KLM-367 clone boards finished and working well. Now onto
> calibration...
> 
> [Back story you can skip]  I decided to assemble them and get them all working
> adequately before I started the calibrating stage. Now, this isn't the first
> time I've done a calibration on the new boards. I tried a partial calibration
> few months back when I got my first board up and running, but part way through
> I decided to stop and wait until I had all the boards done. The process was,
> how shall I put this politely, infuriating(!) as the instructions were vague
> at best with things lost in translation and perhaps a few assumptions made by
> the manual author on the tech/person doing the calibrations and their
> experience/knowledge.
> 
> Now that I'm heading back into calibration mode, I was wondering if any of you
> guys have a plain English interpretation of the instructions. Something a
> little more thorough, and less... Engrish.
> 
> One of the first things I'm having trouble figuring out is what the heck is DC
> Click Noise (Step 7)? And where the heck do I read this from? The Main out? A
> test point? If so, which one? How important is this step?
> 
> I'm just starting out so there might be a bunch more questions down the line.
> Figured I'd start with this one.
> 
> Thanks in advance. And thanks again to Andy for helping me get through the
> assembly and subsequent troubleshooting. You da man!
> 
> Arturo....
> 
> ============================================
> Arturo Brisindi
> 
> [Musics]
> 
> mydadvsyours.com  |  soundcloud.com/arturo00
> 
> [Studios]
> 
> galleryrecording.weebly.com  |  arturo00.weebly.com
> 
>       
> 
> [Non-text portions of this message have been removed]
> 
>  
>    
> 
> 



[Non-text portions of this message have been removed]

Yes it has been acid damaged and has been serviced by another tech before me and has not done a proper repair.

I have checked IC 30 and 31 and had one cable on the wrong place
(my bad :)) 

It now sounds as it should and the modulation of the sound is gone.
All the switches on the 369 is still not working and will have to do a follow up on that. It works on the 370!
The reset circuit is still behaving badly and will replace the pull-down diod D2 and see if it helps?
When I put switch in test mode it wont do any change when I change the DA trim? It did before.

So back with the scope and check some more and thanks for the input so far.

/Robert



--- In PolySix@yahoogroups.com, Andrew Jury <andy@...> wrote:

>
> Hi Robert,
> 
> Are you repairing a board that has been acid damaged? That is an awful lot
> of silicon to be changing in one go! If you can�t set up the reset circuit
> properly and just get a permanent active low in test mode then try replacing
> zener diode D2. As far the switches being in trouble do check the operation
> of the quad latches IC28/29/34/35. Moreover make sure there is a pulse train
> at the clock pin (5). If this board has had an acid spill then the lines
> back to P24/25 on the CPU are prone to becoming disconnected as they run
> under where the battery used to be!
> 
> Cheers,
> Andy  
> 
> 
> 
> 
> On 23/02/2011 17:57, "robobob66" <robertleiner@...> wrote:
> 
> >  
> >  
> >  
> >    
> > 
> > Hello list.
> > 
> > I'm working on a broken KLM367 where i so far have put new logic
> > on IC 30, 31, 24, 26, 28, 29, 34, 35.
> > 
> > When i test the reset circuit with a 56kohm dummy all the leds light up but
> > won't change when i adjust VR1. It only changes when i remove the dummy and
> > adjust on VR1.?
> > 
> > The polysix makes sound and all pots works except all the switches on KLM 369
> > dont work. The sound it self sounds like its being modulated by an fast lfo
> > that wont go away and it's not from the polysix lfo! bad A/D?.
> > 
> > Ok, any light on this matter is help full!
> > 
> > /Robert Leiner
> > 
> >  
> 
> 
> 
> [Non-text portions of this message have been removed]
>