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Subject: Yamaha Voice Card for Sale

From: steve kodnel <dzlvs8@...>
Date: 2011-05-15

If anyone wants a voice card from a Yamaha CS-50, I have one for sale.  It works perfect.  I'm  not sure how much to ask for one but I am going to say $300 obo right now.  
Also, if you need any other parts, please let me know, I may still have them available.Thanks,
Steve


--- On Sat, 5/14/11, jkjelec@... <jkjelec@...> wrote:

From: jkjelec@... <jkjelec@...>
Subject: Re: [yamahacs80] Pitch Drop When Using Sustain 1
To: yamahacs80@yahoogroups.com
Date: Saturday, May 14, 2011, 4:13 PM
















 













OK, this is what I found:



I was thinking that it had to be this, that I cut and saved from AH (I think) a few years ago:



"Seems the SH card collects debris over the years from being near the front  

of the machine, underneath the keyboard, and this reduces its effectiveness  

as an insulator. The impedance of the input to the SH amps (CA3140T) is in  

the order of 1.5 T Ohms (1500 Meg Ohms!) and the SH caps are quite small for  

this application (0.22uF) so it doesn't take much to cause that voltage to  

leak away. Some good old household dust plus several gigs in smokey  

theatres (this was the eighties, don't forget) would probably be enough.



I found if I lifted the end of the caps which feed to the CA3140T's from the  

PCB, Pin 3 of the CA3140T's and also the 4066 Gate outputs and wire-linked  

them together away from the surface of the PCB, the problem goes away. There  

is still a very small voltage drop but even with full Sustain (Yamaha-speak  

for Release) the change in pitch isn't noticeable.



I'm guessing this must be a common fault, as the CS-60 card I have exhibits  

the same problem.



Lucid."



jkjelec



----- Original Message -----

From: "lucidsound" <lucidsound@...>

To: yamahacs80@yahoogroups.com

Sent: Thursday, May 12, 2011 2:33:54 PM

Subject: [yamahacs80] Pitch Drop When Using Sustain 1



Has anyone else come across the quirk whereby if using long release times in Sustain Mode 1, the oscillator pitch drops slowly when the notes are released?  Switching to Sustain II brings the notes back to the correct pitch.



I figure this is something to do with the Keyboard SH card, and voltages leaking away from the capacitors.



Any suggestions or previous experiences of this problem welcome!



Thanks,



Lucid.



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