[sdiy] Polysix Power supply, was Prophet 5 -15v rail is shorting

[Tom Wiltshire]

On 8 Nov 2007, at 15:47, Oakley Sound wrote:

> However, the Polysix does have its own +5v rail derived from its  
> own transformer winding.

Not in either of mine. Both of them use a straightforward centre- 
tapped secondary winding. One of them has been converted from US to  
UK voltage, so doesn't have the original transformer. It outputs  
19.5V-0V-19.5V with no load. The other, which has the original Korg  
transformer, outputs 21-0-21, again with no load. These three wires  
to the power supply board are the only inputs, from which all other  
voltages are derived.

Otherwise, I'm not disagreeing with Tony. Any suitably rated  
transformer will be fine in a Prophet, and using a low-noise toroidal  
transformer sounds like good advice.

Regards,
Tom