OldSynths

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/
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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?