[sdiy] Oberheim OB-Mx PSU question

[Ingo Debus]

Peter Grenader wrote:
> The hum Sebastian is experiencing is due to the fact that the OBMX was
> released in 1993, and at that point Gernam AC was runing about 220.  I've
> been told now it's floating at around 235.  It's transformer is not designed
> to handle this additional voltage, thus it hums.

Yes, the nominal mains voltage here is 230 volts now. It was 220 volts 
about 20 years ago.
I'm pretty sure in 1993 it was already 230 volts.

Anyway if this was designed for 220 volts and doesn't work properly 
with 230 it's a poor design IMHO. That's less than 5% overvoltage.

Ingo