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2008-03-31 by slammah2006
I am down 2 Oscillator cards in Bank 2 (# 3 and # 5) I believe it is the Waveshape chips that are faulty..... Does anyone have any spares, or is know if there is a way to drop a voice out of the rotation giving 2 banks of 7 Oscillators???...If that were the case I could move one from my first bank to bank 2.... Any Ideas???
2008-04-03 by David Rogoff
slammah2006 wrote: > I am down 2 Oscillator cards in Bank 2 (# 3 and # 5) I believe it is > the Waveshape chips that are faulty..... > Does anyone have any spares, Good luck > or is know if there is a way to drop a > voice out of the rotation giving 2 banks of 7 Oscillators???...If that > were the case I could move one from my first bank to bank 2... > This is pretty easy - I've done it before for someone while waiting for an oscillator chip. Move the bad parts to the highest voice cards (e.g. voice 8, then 7). Then you just jumper on the KAS board. If you look at the KAS chip description (http://www.therogoffs.com/cs80/manuals/CS80_Service_Manual/06%20-%20KAS%20ICs.jpg), you can see that changing pin 40 (MODE) from -6.5 to +8.5v skips voice 8. If you have to disable more voices, then you need to change the K01-K08 pins. Look at the difference between the CS80 KAS board (http://www.therogoffs.com/cs80/manuals/CS80_Service_Manual/04%20-%20KAS%20schematic.jpg) and the CS80 KAS board (page 3 of http://www.therogoffs.com/cs80/manuals/CS50_Service_Manual/Yamaha%20CS-50%20Service%20Manual%202%20of%202%20(%2011%20x%2017%20-%20Double%20Sided%20).PDF). Note: when I did this, I just changed the MODE pin (by cutting the far end of the resistor attached to it and connecting it to +8.5v) and didn't tie the K08 pin. This caused the 8th voice to be on all the time and screwed up the trigger to the Ring-Mod EG. I ended up pulling the oscillator chips on the 8th voice M Cards to mute them. However, this created a really weird side-effect. The waveshaper chip was still there and picked up the signal from the PWM oscillator. When the PWM rate was raised, it triggered the WSC and the oscillator was audible all the time! Confused the hell out of me at the time. David
2008-04-03 by Laurie Curry
Is the waveshape chip very sensitive to heat when desoldering??? It is of course, one of the chips without an IC socket............ could it be socket mounted once out or would a socket create more problems???
-----Original message----- From: David Rogoff david@... Date: Wed, 02 Apr 2008 20:26:34 -0700 To: yamahacs80@yahoogroups.com Subject: Re: [yamahacs80] I need 2 M cards slammah2006 wrote: > I am down 2 Oscillator cards in Bank 2 (# 3 and # 5) I believe it is > the Waveshape chips that are faulty..... > Does anyone have any spares, Good luck > or is know if there is a way to drop a > voice out of the rotation giving 2 banks of 7 Oscillators???...If that > were the case I could move one from my first bank to bank 2... > This is pretty easy - I've done it before for someone while waiting for an oscillator chip. Move the bad parts to the highestvoice cards (e.g. voice 8, then 7). Then you just jumper on the KAS board. If you look at the KAS chip description (http://www.therogoffs.com/cs80/manuals/CS80_Service_Manual/06%20-%20KAS%20ICs.jpg), you can see that changing pin 40 (MODE) from -6.5 to +8.5v skips voice 8. If you have to disable more voices, then you need to change the K01-K08 pins. Look at the difference between the CS80 KAS board (http://www.therogoffs.com/cs80/manuals/CS80_Service_Manual/04%20-%20KAS%20schematic.jpg) and the CS80 KAS board (page 3 of http://www.therogoffs.com/cs80/manuals/CS50_Service_Manual/Yamaha%20CS-50%20Service%20Manual%202%20of%202%20(%2011%20x%2017%20-%20Double%20Sided%20).PDF). Note: when I did this, I just changed the MODE pin (by cutting the far end of the resistor attached to it and connecting it to +8.5v) and didn't tie the K08 pin. This caused the 8th voice to be on all the time and screwed up thetrigger to the Ring-Mod EG. I ended up pulling the oscillator chips on the 8th voice M Cards to mute them. However, this created a really weird side-effect. The waveshaper chip was still there and picked up the signal from the PWM oscillator. When the PWM rate was raised, it triggered the WSC and the oscillator was audible all the time! Confused the hell out of me at the time. David [Non-text portions of this message have been removed]
2008-04-03 by Laurie Curry
Oh BTW Thank you David for your suggestions..... I can't believe I forgot to mention that in my last post... Once I can decipher the pin 40 jumper modification on the schematics on the kas,I may feel braver in tackling the m Board rotating....
-----Original message----- From: "Laurie Curry" laurie@... Date: Wed, 02 Apr 2008 21:18:36 -0700 To: yamahacs80@yahoogroups.com Subject: Re: [yamahacs80] I need 2 M cards Is the waveshape chip very sensitive to heat when desoldering??? It is of course, one of the chips without an IC socket............ could it be socket mounted once out or would a socket create more problems??? -----Original message----- From: David Rogoff david@... Date: Wed, 02 Apr 2008 20:26:34 -0700 To: yamahacs80@yahoogroups.com Subject: Re: [yamahacs80] I need 2 M cards slammah2006 wrote: > I am down2 Oscillator cards in Bank 2 (# 3 and # 5) I believe it is > the Waveshape chips that are faulty..... > Does anyone have any spares, Good luck > or is know if there is a way to drop a > voice out of the rotation giving 2 banks of 7 Oscillators???...If that > were the case I could move one from my first bank to bank 2... > This is pretty easy - I've done it before for someone while waiting for an oscillator chip. Move the bad parts to the highestvoice cards (e.g. voice 8, then 7). Then you just jumper on the KAS board. If you look at the KAS chip description (http://www.therogoffs.com/cs80/manuals/CS80_Service_Manual/06%20-%20KAS%20ICs.jpg), you can see that changing pin 40 (MODE) from -6.5 to +8.5v skips voice 8. If you have to disable more voices, then you need to change the K01-K08 pins. Look at the difference between the CS80 KAS board (http://www.therogoffs.com/cs80/manuals/CS80_Service_Manual/04%20-%20KAS%20schematic.jpg) and the CS80 KAS board (page 3 of http://www.therogoffs.com/cs80/manuals/CS50_Service_Manual/Yamaha%20CS-50%20Service%20Manual%202%20of%202%20(%2011%20x%2017%20-%20Double%20Sided%20).PDF). Note: when I did this, I just changed the MODE pin (by cutting the far end of the resistor attached to it and connecting it to +8.5v) and didn't tie the K08 pin. This caused the 8th voice to be on all the time and screwed up thetrigger to the Ring-Mod EG. I ended up pulling the oscillator chips on the 8th voice M Cards to mute them. However, this created a really weird side-effect. The waveshaper chip was still there and picked up the signal from the PWM oscillator. When the PWM rate was raised, it triggered the WSC and the oscillator was audible all the time! Confused the hell out of me at the time. David [Non-text portions of this message have been removed] [Non-text portions of this message have been removed]