Korg Poly800/EX800 Users

I just installed the Hawk 800 kit into my poly800 mkII and it was all working perfectly. I installed the kit and started it up, then flashed it with the sysex files, which also seemed to go fine. I then reatarted it and pressed a key and seemed to get some kind of sound, but then every part of the display lit up at once and it all locked up.

Now when i turn the thing on every part of the display lights up brightly for about half a second and then appear to just go blank, although the whole thing does appear to be lit very dimly if you look carefully.

Does anyone have any ideas on what the problem might be? I've checked all my soldering and made sure everything is connected where it should be.

The annoying this is that on a couple of occassions the poly has started up properly and then the screen has flickered out as soon as i tried to use it, which might indicate an intermittant problem.

Flickering out might indicate a power supply problem, where pressing a  
button puts an additional load on the defective/underpowered power  
supply and causes a CPU reset. Have you tried running on batteries or  
using a different (larger) power supply? -pc

On Nov 4, 2009, at 10:30 AM, crustypaul wrote:

> I just installed the Hawk 800 kit into my poly800 mkII and it was  
> all working perfectly. I installed the kit and started it up, then  
> flashed it with the sysex files, which also seemed to go fine. I  
> then reatarted it and pressed a key and seemed to get some kind of  
> sound, but then every part of the display lit up at once and it all  
> locked up.
>
> Now when i turn the thing on every part of the display lights up  
> brightly for about half a second and then appear to just go blank,  
> although the whole thing does appear to be lit very dimly if you  
> look carefully.
>
> Does anyone have any ideas on what the problem might be? I've  
> checked all my soldering and made sure everything is connected where  
> it should be.
>
> The annoying this is that on a couple of occassions the poly has  
> started up properly and then the screen has flickered out as soon as  
> i tried to use it, which might indicate an intermittant problem.
>
>

On further investigation i don't think this has got anything to do with the Hawk800 and i've just knocked something while installing it.

There appears to be a bizarre problem with something in the power supply area. If i screw the main board down tight the poly starts up fine but the pitch is wavering all over the place, either that or the pitch starts to rise for no apparent reason until the poly restarts. The fact that it starts up might have something to do with the main board grounding. 
If i touch the main board anywhere near the power input the pitch wavers with the amount depending on how hard i press on the board. If i press it too hard the poly just resets.
I'm thinking theres some kind of intermittant short around the power supply somewhere but it could take some time to track it down. Would the fact that the pitch is actually proportional to how hard i press on the board suggest what component has the problem to anyone?



--- In korgpolyex@yahoogroups.com, Paul Cunningham <paul@...> wrote:

>
> Flickering out might indicate a power supply problem, where pressing a  
> button puts an additional load on the defective/underpowered power  
> supply and causes a CPU reset. Have you tried running on batteries or  
> using a different (larger) power supply? -pc

Paul,

I would start with a multimeter and measure the +5volt rail and carefully adjust it using VR1 near the power regulator (top left hand corner looking from the front of the main board).

I've had two HAWK-800 customers with kits that placed just a little more load on the power supply to bring it under the required minimum (+4.75).

You should adjust it to be as close to +5.0 volts as you can. CAUTION: Be careful not to send the power too far over 5 volts.

Then go looking for your intermittent problem.

Mike.





________________________________
From: crustypaul <bullshit@...>
To: korgpolyex@yahoogroups.com
Sent: Wed, November 4, 2009 1:23:54 PM
Subject: [korgpolyex] Re: Killed my poly mkII installing Hawk800 kit

  
On further investigation i don't think this has got anything to do with the Hawk800 and i've just knocked something while installing it.

There appears to be a bizarre problem with something in the power supply area. If i screw the main board down tight the poly starts up fine but the pitch is wavering all over the place, either that or the pitch starts to rise for no apparent reason until the poly restarts. The fact that it starts up might have something to do with the main board grounding. 
If i touch the main board anywhere near the power input the pitch wavers with the amount depending on how hard i press on the board. If i press it too hard the poly just resets.
I'm thinking theres some kind of intermittant short around the power supply somewhere but it could take some time to track it down. Would the fact that the pitch is actually proportional to how hard i press on the board suggest what component has the problem to anyone?

--- In korgpolyex@yahoogro ups.com, Paul Cunningham <paul@...> wrote:

>
> Flickering out might indicate a power supply problem, where pressing a 
> button puts an additional load on the defective/underpowe red power 
> supply and causes a CPU reset. Have you tried running on batteries or 
> using a different (larger) power supply? -pc

Hi mike,
That was one of the first things i checked. Slightly worryingly just after i had installed the Hawk800 and finally got it to restart, the 5v rail seemed to be at about 5.8v but i've trimmed it back to 5v.

I think this is definately a grounding issue somewhere. If i replace the main board and tighten all the screws as much as i can, with all the ground leads and sheilding connections in place then it appears to work fine no matter how hard i poke the board, although i'm not really that keen on just relying on the fact that it works without actually knowing why. I guess i'll have to just put in the time and go component by component to track down the problem.

By the way, is there an issue with the Hawk800 firmware and the DCO modulation when you use the Joystick? If i push the joystick up and introduce DCO modulation, and then let the joystick go so it snaps back into place, then 80% of the time the modulation remains on the sound. If i move the joystick back to its resting position by hand the modulation is reduced and then disappears completely as normal. Its as if if you let it snap back there isn't enough data resolution to catch the settings in between maximum and zero, so when it moves that fast you're left with the maximum setting.





--- In korgpolyex@yahoogroups.com, Michael Hawkins <korgpolyex800@...> wrote:

>
> Paul,
> 
> I would start with a multimeter and measure the +5volt rail and carefully adjust it using VR1 near the power regulator (top left hand corner looking from the front of the main board).
> 
> I've had two HAWK-800 customers with kits that placed just a little more load on the power supply to bring it under the required minimum (+4.75).
> 
> You should adjust it to be as close to +5.0 volts as you can. CAUTION: Be careful not to send the power too far over 5 volts.
> 
> Then go looking for your intermittent problem.
> 
> Mike.
> 
>

Yes, the joystick does get stuck when you let it flick back to the center position.

I shall log this as a bug and get it fixed in the next version of the firmware.

Are you running the latest version of the software - that is 2.4.2?

Mike




________________________________
From: crustypaul <bullshit@...>
To: korgpolyex@yahoogroups.com
Sent: Wed, November 4, 2009 5:58:29 PM
Subject: [korgpolyex] Re: Killed my poly mkII installing Hawk800 kit

  
Hi mike,
That was one of the first things i checked. Slightly worryingly just after i had installed the Hawk800 and finally got it to restart, the 5v rail seemed to be at about 5.8v but i've trimmed it back to 5v.

I think this is definately a grounding issue somewhere. If i replace the main board and tighten all the screws as much as i can, with all the ground leads and sheilding connections in place then it appears to work fine no matter how hard i poke the board, although i'm not really that keen on just relying on the fact that it works without actually knowing why. I guess i'll have to just put in the time and go component by component to track down the problem.

By the way, is there an issue with the Hawk800 firmware and the DCO modulation when you use the Joystick? If i push the joystick up and introduce DCO modulation, and then let the joystick go so it snaps back into place, then 80% of the time the modulation remains on the sound. If i move the joystick back to its resting position by hand the modulation is reduced and then disappears completely as normal. Its as if if you let it snap back there isn't enough data resolution to catch the settings in between maximum and zero, so when it moves that fast you're left with the maximum setting.

--- In korgpolyex@yahoogro ups.com, Michael Hawkins <korgpolyex800@ ...> wrote:

>
> Paul,
> 
> I would start with a multimeter and measure the +5volt rail and carefully adjust it using VR1 near the power regulator (top left hand corner looking from the front of the main board).
> 
> I've had two HAWK-800 customers with kits that placed just a little more load on the power supply to bring it under the required minimum (+4.75).
> 
> You should adjust it to be as close to +5.0 volts as you can. CAUTION: Be careful not to send the power too far over 5 volts.
> 
> Then go looking for your intermittent problem.
> 
> Mike.
> 
>

Well heres a weird thing. I have two Poly800 mkII main boards, one labelled KLM-1032-A and the other labelled KLM-1032-B EMI. The one labelled as A has a single ground but the one labelled B, which is the one i'm having trouble with, appears to have a separate analogue and digital ground which is joined via the shielding under the board. Theres a lot more in tha way of shielding on the B model. If the two grounds aren't connected then the poly doesn't seem to start up properly. If they are connected but not very well then you seem to get the pitch wavering that i was getting earlier. Odd.
Presumably the EMI in the B boards serial number stands for Electro Magnetic Interference, which is what the dual grounds and extra shielding are trying to get rid of. I've worked on a few Poly800's  and i've never seen the EMI board before.

Yes, I'm running the 2.4.2 software.




--- In korgpolyex@yahoogroups.com, Michael Hawkins <korgpolyex800@...> wrote:

>
> Yes, the joystick does get stuck when you let it flick back to the center position.
> 
> I shall log this as a bug and get it fixed in the next version of the firmware.
> 
> Are you running the latest version of the software - that is 2.4.2?
> 
> Mike
> 
> 
> 
> 
> ________________________________
> From: crustypaul <bullshit@...>
> To: korgpolyex@yahoogroups.com
> Sent: Wed, November 4, 2009 5:58:29 PM
> Subject: [korgpolyex] Re: Killed my poly mkII installing Hawk800 kit
> 
>   
> Hi mike,
> That was one of the first things i checked. Slightly worryingly just after i had installed the Hawk800 and finally got it to restart, the 5v rail seemed to be at about 5.8v but i've trimmed it back to 5v.
> 
> I think this is definately a grounding issue somewhere. If i replace the main board and tighten all the screws as much as i can, with all the ground leads and sheilding connections in place then it appears to work fine no matter how hard i poke the board, although i'm not really that keen on just relying on the fact that it works without actually knowing why. I guess i'll have to just put in the time and go component by component to track down the problem.
> 
> By the way, is there an issue with the Hawk800 firmware and the DCO modulation when you use the Joystick? If i push the joystick up and introduce DCO modulation, and then let the joystick go so it snaps back into place, then 80% of the time the modulation remains on the sound. If i move the joystick back to its resting position by hand the modulation is reduced and then disappears completely as normal. Its as if if you let it snap back there isn't enough data resolution to catch the settings in between maximum and zero, so when it moves that fast you're left with the maximum setting.
> 
> --- In korgpolyex@yahoogro ups.com, Michael Hawkins <korgpolyex800@ ...> wrote:
> >
> > Paul,
> > 
> > I would start with a multimeter and measure the +5volt rail and carefully adjust it using VR1 near the power regulator (top left hand corner looking from the front of the main board).
> > 
> > I've had two HAWK-800 customers with kits that placed just a little more load on the power supply to bring it under the required minimum (+4.75).
> > 
> > You should adjust it to be as close to +5.0 volts as you can. CAUTION: Be careful not to send the power too far over 5 volts.
> > 
> > Then go looking for your intermittent problem.
> > 
> > Mike.
> > 
> >
>

So does that mean that your MK2 with HAWK is working OK now?




________________________________
From: crustypaul <bullshit@...>
To: korgpolyex@yahoogroups.com
Sent: Wed, November 4, 2009 8:37:59 PM
Subject: [korgpolyex] Re: Didn't kill my poly mkII installing Hawk800 kit ;-)

  
Well heres a weird thing. I have two Poly800 mkII main boards, one labelled KLM-1032-A and the other labelled KLM-1032-B EMI. The one labelled as A has a single ground but the one labelled B, which is the one i'm having trouble with, appears to have a separate analogue and digital ground which is joined via the shielding under the board. Theres a lot more in tha way of shielding on the B model. If the two grounds aren't connected then the poly doesn't seem to start up properly. If they are connected but not very well then you seem to get the pitch wavering that i was getting earlier. Odd.
Presumably the EMI in the B boards serial number stands for Electro Magnetic Interference, which is what the dual grounds and extra shielding are trying to get rid of. I've worked on a few Poly800's  and i've never seen the EMI board before.

Yes, I'm running the 2.4.2 software.

--- In korgpolyex@yahoogro ups.com, Michael Hawkins <korgpolyex800@ ...> wrote:

>
> Yes, the joystick does get stuck when you let it flick back to the center position.
> 
> I shall log this as a bug and get it fixed in the next version of the firmware.
> 
> Are you running the latest version of the software - that is 2.4.2?
> 
> Mike
> 
> 
> 
> 
> ____________ _________ _________ __
> From: crustypaul <bullshit@.. .>
> To: korgpolyex@yahoogro ups.com
> Sent: Wed, November 4, 2009 5:58:29 PM
> Subject: [korgpolyex] Re: Killed my poly mkII installing Hawk800 kit
> 
> 
> Hi mike,
> That was one of the first things i checked. Slightly worryingly just after i had installed the Hawk800 and finally got it to restart, the 5v rail seemed to be at about 5.8v but i've trimmed it back to 5v.
> 
> I think this is definately a grounding issue somewhere. If i replace the main board and tighten all the screws as much as i can, with all the ground leads and sheilding connections in place then it appears to work fine no matter how hard i poke the board, although i'm not really that keen on just relying on the fact that it works without actually knowing why. I guess i'll have to just put in the time and go component by component to track down the problem.
> 
> By the way, is there an issue with the Hawk800 firmware and the DCO modulation when you use the Joystick? If i push the joystick up and introduce DCO modulation, and then let the joystick go so it snaps back into place, then 80% of the time the modulation remains on the sound. If i move the joystick back to its resting position by hand the modulation is reduced and then disappears completely as normal. Its as if if you let it snap back there isn't enough data resolution to catch the settings in between maximum and zero, so when it moves that fast you're left with the maximum setting.
> 
> --- In korgpolyex@yahoogro ups.com, Michael Hawkins <korgpolyex800@ ...> wrote:
> >
> > Paul,
> > 
> > I would start with a multimeter and measure the +5volt rail and carefully adjust it using VR1 near the power regulator (top left hand corner looking from the front of the main board).
> > 
> > I've had two HAWK-800 customers with kits that placed just a little more load on the power supply to bring it under the required minimum (+4.75).
> > 
> > You should adjust it to be as close to +5.0 volts as you can. CAUTION: Be careful not to send the power too far over 5 volts.
> > 
> > Then go looking for your intermittent problem.
> > 
> > Mike.
> > 
> >
>

--- In korgpolyex@yahoogroups.com, "crustypaul" <bullshit@...> wrote:
>
> On further investigation i don't think this has got anything to do with the Hawk800 and i've just knocked something while installing it.
> 

Yeah I think these things might be fragile, I recently discovered that mine stopped working after I threw my sweater on it a few times.  It all starts up ok with the 11 P on display, but none of the patches work and adjusting the parameters doesn't work either, only the filter seems to work now.  I'll probably give fixing it a quick try but I am not going to waste much time on it, so if anyone thinks it might be worth something to them for parts, let me know (here, don't email me, this account is full of spam and I dont read it)

I think the actual Hawk800 was always working but i was having other issues entirely. The only real issues i had with the Hawk was that the smaller IC socket ribbon connector kept popping out of the socket but i see you mentioned that in the manual. I might get a better quality socket asnd see if that helps, or cable tie it in.
Everything appears to be working fine as far as the Hawk800 is concerned so you can count that as a successfull install.


--- In korgpolyex@yahoogroups.com, Michael Hawkins <korgpolyex800@...> wrote:

>
> So does that mean that your MK2 with HAWK is working OK now?
>

and a successfull Atomahawk installation as well. ;)

You might want to point out in the troubleshooting bit from the moog slayer section in the atomahawk manual that the 'aggressive resonance' switch might not work if the resonance trimmer pot on the board is adjusted lower than it should be. 
I was convinced for ages that i'd wired something up wrong as the resonance wasn't going into self oscillation when i switched it on. After a couple of hours messing aroud with it i finally realised that if i just turned up the resonance on the board the aggressive resonance works perfectly. Whoops!


--- In korgpolyex@yahoogroups.com, "crustypaul" <bullshit@...> wrote:

>
> I think the actual Hawk800 was always working but i was having other issues entirely. The only real issues i had with the Hawk was that the smaller IC socket ribbon connector kept popping out of the socket but i see you mentioned that in the manual. I might get a better quality socket asnd see if that helps, or cable tie it in.
> Everything appears to be working fine as far as the Hawk800 is concerned so you can count that as a successfull install.
> 
> 
> --- In korgpolyex@yahoogroups.com, Michael Hawkins <korgpolyex800@> wrote:
> >
> > So does that mean that your MK2 with HAWK is working OK now?
> >
>