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About the NJM2069 Chip

About the NJM2069 Chip

2014-06-02 by ackolonges

Hi All,

I've been searching high and low for schematics and other information about using the filter/VCA chip in a standalone module but still have a few questions.  Has anyone out there used this chip outside the Korg synths and would be willing to share the schematic?

On some sites it's been said that the power is +5v GND -5v and other sites have said +12v GND -5v, does anyone know which of these is correct?  Also I'm having a hard time making out the values of the filter capacitors on pins 15, 16, 17 and 18.  I only have the chip and not the Poly-800 any more, so could anyone help me with this?

Thanks a lot.

Re: About the NJM2069 Chip

2014-06-02 by korgpolyex800@...

http://sounddoctorin.com/synthtec/korg/njm2069.htm

There was a block diagram somewhere but I just don't seem to be able to find it anywhere. Maybe someone else can link to it.

http://sounddoctorin.com/synthtec/korg/njm2069.htm
     The following preformatted information was provided by some people in the synth diy group and is a wealth of information about this hard to find info on chip! Larry Hendry sadly passed away shortly after this and his contributions of this nature are greatly missed.
View on sounddoctorin.com
Preview by Yahoo

 

Re: About the NJM2069 Chip

2014-06-03 by bperkins211@...

you can find a block diagram of the IC chip inside the Korg Poly 800 service manual.

It is best to check the schematics inside a Poly 800, or DW 8000 to find a known working schematic for using the chips.  Just copy what Korg did..  but maybe configure it so you can switch between -12db and -24db outputs.

Re: About the NJM2069 Chip

2014-06-03 by bperkins211@...

yes he did.

I also have had long discussion with Paul about the DW8000 filter board and he said when it came to using a NJM2069 in his synth, he just copied Korg's schematics.


---In korgpolyex@yahoogroups.com, <josh.nursing@...> wrote :

Paul Maddox of Vacoloco has built a standalone synth with the chip.

RE: [korgpolyex] Re: About the NJM2069 Chip

2014-06-04 by ackolonges

Thanks for your feedback everybody.  The values of the capacitors are written in the DW8000 schematics as 0.001 with no units, so I suppose the filter capacitors are all 1n.  By accounts it looks like the positive voltage was +5v in the poly800 and +12v for the DW8000. Since I'd like to use +/-12v standard modular CVs I guess I should go with +12v.  I just hope I don't blow it, since I've only got one.


To: korgpolyex@yahoogroups.com
From: korgpolyex@yahoogroups.com
Date: Tue, 3 Jun 2014 09:59:01 -0700
Subject: [korgpolyex] Re: About the NJM2069 Chip

 
yes he did.

I also have had long discussion with Paul about the DW8000 filter board and he said when it came to using a NJM2069 in his synth, he just copied Korg's schematics.


---In korgpolyex@yahoogroups.com, <josh.nursing@...> wrote :

Paul Maddox of Vacoloco has built a standalone synth with the chip.

Re: [korgpolyex] Re: About the NJM2069 Chip

2014-06-04 by Michael Hawkins

No one has the spec for the chip. So there's no datasheet to go to unfortunately. I pestered Korg for months. They tried very hard to find the details of it. Oki were also quite friendly but they too could not help.

I would check the DW8000 schematic carefully and see what the supply pins are connected to very, very carefully.

Pin 22 is Vcc - in the Poly, it's connected to +5V
Pin 11 is Ground (0V) - in the Poly, it's connected to ground - 0 volts.
Pin 12 is Vee - in the Poly, it's connected to -5V

It makes sense that the thing is CMOS, in which case, it can run in dual supply mode (as Poly above) or in single supply mode (DW8000 perhaps?) where Vcc is +12 and Vee is tied to ground.

But you will need to check this.

Mike



On Tuesday, June 3, 2014 9:22 PM, "ackolonges ackolonges@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:


 
Thanks for your feedback everybody.  The values of the capacitors are written in the DW8000 schematics as 0.001 with no units, so I suppose the filter capacitors are all 1n.  By accounts it looks like the positive voltage was +5v in the poly800 and +12v for the DW8000. Since I'd like to use +/-12v standard modular CVs I guess I should go with +12v.  I just hope I don't blow it, since I've only got one.


To: korgpolyex@yahoogroups.com
From: korgpolyex@yahoogroups.com
Date: Tue, 3 Jun 2014 09:59:01 -0700
Subject: [korgpolyex] Re: About the NJM2069 Chip

 
yes he did.

I also have had long discussion with Paul about the DW8000 filter board and he said when it came to using a NJM2069 in his synth, he just copied Korg's schematics.


---In korgpolyex@yahoogroups.com, <josh.nursing@...> wrote :

Paul Maddox of Vacoloco has built a standalone synth with the chip.



Re: [korgpolyex] Re: About the NJM2069 Chip

2014-06-04 by Harlan Foster

Here is some decent info about the NJM2069. Not a datasheet, but better than nothing!
http://sounddoctorin.com/synthtec/korg/njm2069.htm


On Tue, Jun 3, 2014 at 6:58 PM, Michael Hawkins korgpolyex800@... [korgpolyex] <korgpolyex@yahoogroups.com> wrote:
 

No one has the spec for the chip. So there's no datasheet to go to unfortunately. I pestered Korg for months. They tried very hard to find the details of it. Oki were also quite friendly but they too could not help.

I would check the DW8000 schematic carefully and see what the supply pins are connected to very, very carefully.

Pin 22 is Vcc - in the Poly, it's connected to +5V
Pin 11 is Ground (0V) - in the Poly, it's connected to ground - 0 volts.
Pin 12 is Vee - in the Poly, it's connected to -5V

It makes sense that the thing is CMOS, in which case, it can run in dual supply mode (as Poly above) or in single supply mode (DW8000 perhaps?) where Vcc is +12 and Vee is tied to ground.

But you will need to check this.

Mike



On Tuesday, June 3, 2014 9:22 PM, "ackolonges ackolonges@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:


 
Thanks for your feedback everybody.  The values of the capacitors are written in the DW8000 schematics as 0.001 with no units, so I suppose the filter capacitors are all 1n.  By accounts it looks like the positive voltage was +5v in the poly800 and +12v for the DW8000. Since I'd like to use +/-12v standard modular CVs I guess I should go with +12v.  I just hope I don't blow it, since I've only got one.


To: korgpolyex@yahoogroups.com
From: korgpolyex@yahoogroups.com
Date: Tue, 3 Jun 2014 09:59:01 -0700
Subject: [korgpolyex] Re: About the NJM2069 Chip

 
yes he did.

I also have had long discussion with Paul about the DW8000 filter board and he said when it came to using a NJM2069 in his synth, he just copied Korg's schematics.


---In korgpolyex@yahoogroups.com, <josh.nursing@...> wrote :

Paul Maddox of Vacoloco has built a standalone synth with the chip.




Re: [korgpolyex] Re: About the NJM2069 Chip

2014-06-04 by Martin Ator

http://www.amsynths.co.uk/Filter_Bank/AM8069/am8069.html        used to sell a circuit board (or considered selling) for DIY but he's recently updated all his site and that stuff seems to be missing.

His used +12V and -5V.

The new page is
http://www.amsynths.co.uk/products/filters/am8069-vcf-vca/


On Wednesday, 4 June 2014, 6:24, "Harlan Foster harlan.foster@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:


 
Here is some decent info about the NJM2069. Not a datasheet, but better than nothing!
http://sounddoctorin.com/synthtec/korg/njm2069.htm


On Tue, Jun 3, 2014 at 6:58 PM, Michael Hawkins korgpolyex800@... [korgpolyex] <korgpolyex@yahoogroups.com> wrote:
 
No one has the spec for the chip. So there's no datasheet to go to unfortunately. I pestered Korg for months. They tried very hard to find the details of it. Oki were also quite friendly but they too could not help.

I would check the DW8000 schematic carefully and see what the supply pins are connected to very, very carefully.

Pin 22 is Vcc - in the Poly, it's connected to +5V
Pin 11 is Ground (0V) - in the Poly, it's connected to ground - 0 volts.
Pin 12 is Vee - in the Poly, it's connected to -5V

It makes sense that the thing is CMOS, in which case, it can run in dual supply mode (as Poly above) or in single supply mode (DW8000 perhaps?) where Vcc is +12 and Vee is tied to ground.

But you will need to check this.

Mike



On Tuesday, June 3, 2014 9:22 PM, "ackolonges ackolonges@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:


 
Thanks for your feedback everybody.  The values of the capacitors are written in the DW8000 schematics as 0.001 with no units, so I suppose the filter capacitors are all 1n.  By accounts it looks like the positive voltage was +5v in the poly800 and +12v for the DW8000. Since I'd like to use +/-12v standard modular CVs I guess I should go with +12v.  I just hope I don't blow it, since I've only got one.


To: korgpolyex@yahoogroups.com
From: korgpolyex@yahoogroups.com
Date: Tue, 3 Jun 2014 09:59:01 -0700
Subject: [korgpolyex] Re: About the NJM2069 Chip

 
yes he did.

I also have had long discussion with Paul about the DW8000 filter board and he said when it came to using a NJM2069 in his synth, he just copied Korg's schematics.


---In korgpolyex@yahoogroups.com, <josh.nursing@...> wrote :

Paul Maddox of Vacoloco has built a standalone synth with the chip.






RE: [korgpolyex] Re: About the NJM2069 Chip

2014-06-04 by ackolonges

Yes that is the page where one person says

"Pin 12 Vee is also -5 volts in the DSS-1
Pin 22 Vcc is actually +12 volts in the DSS-1"
and another person posts a pinout with Vee at -5v and Vcc at +5v.


To: korgpolyex@yahoogroups.com
From: korgpolyex@yahoogroups.com
Date: Tue, 3 Jun 2014 22:24:28 -0700
Subject: Re: [korgpolyex] Re: About the NJM2069 Chip

 
Here is some decent info about the NJM2069. Not a datasheet, but better than nothing!
http://sounddoctorin.com/synthtec/korg/njm2069.htm


On Tue, Jun 3, 2014 at 6:58 PM, Michael Hawkins korgpolyex800@... [korgpolyex] <korgpolyex@yahoogroups.com> wrote:
 


No one has the spec for the chip. So there's no datasheet to go to unfortunately. I pestered Korg for months. They tried very hard to find the details of it. Oki were also quite friendly but they too could not help.

I would check the DW8000 schematic carefully and see what the supply pins are connected to very, very carefully.

Pin 22 is Vcc - in the Poly, it's connected to +5V
Pin 11 is Ground (0V) - in the Poly, it's connected to ground - 0 volts.
Pin 12 is Vee - in the Poly, it's connected to -5V

It makes sense that the thing is CMOS, in which case, it can run in dual supply mode (as Poly above) or in single supply mode (DW8000 perhaps?) where Vcc is +12 and Vee is tied to ground.

But you will need to check this.

Mike



On Tuesday, June 3, 2014 9:22 PM, "ackolonges ackolonges@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:


 
Thanks for your feedback everybody.  The values of the capacitors are written in the DW8000 schematics as 0.001 with no units, so I suppose the filter capacitors are all 1n.  By accounts it looks like the positive voltage was +5v in the poly800 and +12v for the DW8000. Since I'd like to use +/-12v standard modular CVs I guess I should go with +12v.  I just hope I don't blow it, since I've only got one.


To: korgpolyex@yahoogroups.com
From: korgpolyex@yahoogroups.com
Date: Tue, 3 Jun 2014 09:59:01 -0700
Subject: [korgpolyex] Re: About the NJM2069 Chip

 
yes he did.

I also have had long discussion with Paul about the DW8000 filter board and he said when it came to using a NJM2069 in his synth, he just copied Korg's schematics.


---In korgpolyex@yahoogroups.com, <josh.nursing@...> wrote :

Paul Maddox of Vacoloco has built a standalone synth with the chip.