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Subject: Re: [oldsynths] Tech Question on Yamaha CS-50

From: The Old Crow <oldcrow@...>
Date: 2004-04-15

Tuning a CS-50 is almost the same as tuning a CS-80. In fact it is much
easier (4 cards to adjust vs. 16). Before adjusting any of the power
supply trimmers, measure the output voltages to see if they are within 10%
of the expected values. If a supply trimmer needs adjusted, try to get
the output as close to the ideal value (e.g., +8.500V). I have an image
of the original CS-50 power supply PC board here:

http://www.oldcrows.net/~oldcrow/synth/yamaha/cs50/CS50_power_supply_layout.gif

VR1: adjusts the +15V
VR2: adjusts the -15V
VR3: adjusts the +8.5V
VR4: adjusts the -6.5V

Adjustment of KAS and M boards is the same as on a CS-80.

Crow
http://www.cs80.com/
/∗∗/

On Wed, 14 Apr 2004, Jim Combs wrote:

> Hi all,
>
> I need to do some basic maintenance on my CS-50 and am looking for a
> copy of a tech manual or some instructions on the following.
>
> - Checking and adjusting the power supply DC output.
> - Getting the overall tuning back into range so I have leeway to adjust up
> and down
> - Adjustment or scaling of individual notes or voices
>
> I have seen the online documentation on the CS-80, but the modules look
> different enough that I think the CS-50/60 probably have their own
> specific steps and values.
>
> Anyone have info that might help?