Vintage Synth Repair

I am getting an MS50 that at the present time in operating on 220v. Can 
the current power supply handle 110 and 220. The Manufacturers' Plate 
on the back states that its Voltage is "Local Voltage"  50/60 Hz. I 
know I can get a step up converter to run it. I also have a power 
supply from a Poly 6 which I think puts out the required 18 volts that 
I probably could put into it. Can anyone help me out with any info or 
past experiences with this synth?

Thanks,
    Jim

> I am getting an MS50 that at the present time in operating on 220v. Can 
> the current power supply handle 110 and 220. The Manufacturers' Plate 

If it can't be switched between the two voltages, I recommend replacing 
the 220V AC/AC transformer with a 110V one. Even the schematics shows 
two part numbers for the transformer, which I reckon point to 220V and 
110V models.

Anyway, look for a transformer which outputs around 12-15VAC and has 
dual output, this is needed for the +/-15VDC regulator stage. 12VAC 
output, when rectified to DC, might be a bit low according to the 
7xxx-series regulator specs (iirc input should be 3V above the specced 
output voltage), but it should work anyway.. Or well, at least I haven't 
had any problems even if the DC on the input side of a given 7xxx 
regulator has been at least 1V above the output ;). The more in excess 
you go above 3V, the more voltage the regulators have to "lose" 
somewhere (= heat).

If there's plenty of room inside the case you can even leave the 220V 
one disconnected inside the synth and mount the 110V next to it. Just 
take a look at the schematics (google if you don't have them), the PSU 
is about as basic as it gets :)

Hope this helps,
.Arto.